Merge remote-tracking branch 'h2database/master' into append-single

h2/pom.xml

@@ -109,6 +109,12 @@
       <version>4.12</version>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.ow2.asm</groupId>
+      <artifactId>asm</artifactId>
+      <version>6.1</version>
+      <scope>test</scope>
+    </dependency>
     <!-- END TEST DEPENDENCIES !-->
   </dependencies>
 

h2/src/docsrc/html/changelog.html

@@ -21,6 +21,14 @@ Change Log
 
 <h2>Next Version (unreleased)</h2>
 <ul>
+<li>Issue #1618: GROUP BY does not work with two identical columns in selected expressions
+</li>
+<li>Issue #1619: Two-phase commit regression in MASTER
+</li>
+<li>PR #1626: fix doc
+</li>
+<li>PR #1625: Prepare to release: javadoc cleanup, fix maven build, fix javadoc build
+</li>
 <li>Issue #1620: UUIDs are unexpectedly sorted as signed
 </li>
 <li>PR #1614: Use bulk .addAll() operation

h2/src/main/org/h2/command/Parser.java

@@ -6940,6 +6940,13 @@ public class Parser {
         return command;
     }
 
+    /**
+     * Checks the table is the DUAL special table.
+     *
+     * @param tableName table name.
+     * @return {@code true} if the table is DUAL special table. Otherwise returns {@code false}.
+     * @see <a href="https://en.wikipedia.org/wiki/DUAL_table">Wikipedia: DUAL table</a>
+     */
     boolean isDualTable(String tableName) {
         return ((schemaName == null || equalsToken(schemaName, "SYS")) && equalsToken("DUAL", tableName))
                 || (database.getMode().sysDummy1 && (schemaName == null || equalsToken(schemaName, "SYSIBM"))

h2/src/main/org/h2/command/dml/Query.java

@@ -52,8 +52,14 @@ public abstract class Query extends Prepared {
      */
     Expression[] expressionArray;
 
+    /**
+     * Describes elements of the ORDER BY clause of a query.
+     */
     ArrayList<SelectOrderBy> orderList;
 
+    /**
+     *  A sort order represents an ORDER BY clause in a query.
+     */
     SortOrder sort;
 
     /**
@@ -459,6 +465,18 @@ public abstract class Query extends Prepared {
         }
     }
 
+    /**
+     * Initialize the 'ORDER BY' or 'DISTINCT' expressions.
+     *
+     * @param session the session
+     * @param expressions the select list expressions
+     * @param expressionSQL the select list SQL snippets
+     * @param e the expression.
+     * @param visible the number of visible columns in the select list
+     * @param mustBeInResult all order by expressions must be in the select list
+     * @param filters the table filters.
+     * @return index on the expression in the {@link #expressions} list.
+     */
     static int initExpression(Session session, ArrayList<Expression> expressions,
             ArrayList<String> expressionSQL, Expression e, int visible, boolean mustBeInResult,
             ArrayList<TableFilter> filters) {
@@ -690,6 +708,11 @@ public abstract class Query extends Prepared {
         return visitor.getMaxDataModificationId();
     }
 
+    /**
+     * Appends query limits info to the plan.
+     *
+     * @param buff query plan string builder.
+     */
     void appendLimitToSQL(StringBuilder buff) {
         if (offsetExpr != null) {
             String count = StringUtils.unEnclose(offsetExpr.getSQL());

h2/src/main/org/h2/command/dml/Select.java

@@ -108,6 +108,9 @@ public class Select extends Query {
     SelectGroups groupData;
 
     private int havingIndex;
+
+    private int[] groupByCopies;
+
     boolean isGroupQuery;
     private boolean isGroupSortedQuery;
     private boolean isWindowQuery;
@@ -462,7 +465,8 @@ public class Select extends Query {
 
     void updateAgg(int columnCount, int stage) {
         for (int i = 0; i < columnCount; i++) {
-            if (groupByExpression == null || !groupByExpression[i]) {
+            if ((groupByExpression == null || !groupByExpression[i])
+                    && (groupByCopies == null || groupByCopies[i] < 0)) {
                 Expression expr = expressions.get(i);
                 expr.updateAggregate(session, stage);
             }
@@ -480,6 +484,13 @@ public class Select extends Query {
                 if (groupByExpression != null && groupByExpression[j]) {
                     continue;
                 }
+                if (groupByCopies != null) {
+                    int original = groupByCopies[j];
+                    if (original >= 0) {
+                        row[j] = row[original];
+                        continue;
+                    }
+                }
                 Expression expr = expressions.get(j);
                 row[j] = expr.getValue(session);
             }
@@ -1047,7 +1058,7 @@ public class Select extends Query {
                 for (int j = 0; j < expSize; j++) {
                     String s2 = expressionSQL.get(j);
                     if (db.equalsIdentifiers(s2, sql)) {
-                        found = j;
+                        found = mergeGroupByExpressions(db, j, expressionSQL, false);
                         break;
                     }
                 }
@@ -1056,12 +1067,12 @@ public class Select extends Query {
                     for (int j = 0; j < expSize; j++) {
                         Expression e = expressions.get(j);
                         if (db.equalsIdentifiers(sql, e.getAlias())) {
-                            found = j;
+                            found = mergeGroupByExpressions(db, j, expressionSQL, true);
                             break;
                         }
                         sql = expr.getAlias();
                         if (db.equalsIdentifiers(sql, e.getAlias())) {
-                            found = j;
+                            found = mergeGroupByExpressions(db, j, expressionSQL, true);
                             break;
                         }
                     }
@@ -1074,6 +1085,14 @@ public class Select extends Query {
                     groupIndex[i] = found;
                 }
             }
+            checkUsed: if (groupByCopies != null) {
+                for (int i : groupByCopies) {
+                    if (i >= 0) {
+                        break checkUsed;
+                    }
+                }
+                groupByCopies = null;
+            }
             groupByExpression = new boolean[expressions.size()];
             for (int gi : groupIndex) {
                 groupByExpression[gi] = true;
@@ -1092,6 +1111,50 @@ public class Select extends Query {
         checkInit = true;
     }
 
+    private int mergeGroupByExpressions(Database db, int index, ArrayList<String> expressionSQL, boolean scanPrevious)
+    {
+        /*
+         * -1: uniqueness of expression is not known yet
+         *
+         * -2: expression that is used as a source for a copy or does not have
+         * copies
+         *
+         * >=0: expression is a copy of expression at this index
+         */
+        if (groupByCopies != null) {
+            int c = groupByCopies[index];
+            if (c >= 0) {
+                return c;
+            } else if (c == -2) {
+                return index;
+            }
+        } else {
+            groupByCopies = new int[expressionSQL.size()];
+            Arrays.fill(groupByCopies, -1);
+        }
+        String sql = expressionSQL.get(index);
+        if (scanPrevious) {
+            /*
+             * If expression was matched using an alias previous expressions may
+             * be identical.
+             */
+            for (int i = 0; i < index; i++) {
+                if (db.equalsIdentifiers(sql, expressionSQL.get(i))) {
+                    index = i;
+                    break;
+                }
+            }
+        }
+        int l = expressionSQL.size();
+        for (int i = index + 1; i < l; i++) {
+            if (db.equalsIdentifiers(sql, expressionSQL.get(i))) {
+                groupByCopies[i] = index;
+            }
+        }
+        groupByCopies[index] = -2;
+        return index;
+    }
+
     @Override
     public void prepare() {
         if (isPrepared) {

h2/src/main/org/h2/command/dml/SelectGroups.java

@@ -194,8 +194,14 @@ public abstract class SelectGroups {
         }
     }
 
+    /**
+     * The session.
+     */
     final Session session;
 
+    /**
+     * The query's column list, including invisible expressions such as order by expressions.
+     */
     final ArrayList<Expression> expressions;
 
     /**
@@ -235,6 +241,7 @@ public abstract class SelectGroups {
      *            is this query is a group query
      * @param groupIndex
      *            the indexes of group expressions, or null
+     * @return new instance of the grouped data.
      */
     public static SelectGroups getInstance(Session session, ArrayList<Expression> expressions, boolean isGroupQuery,
             int[] groupIndex) {
@@ -247,7 +254,10 @@ public abstract class SelectGroups {
     }
 
     /**
-     * Is there currently a group-by active
+     * Is there currently a group-by active.
+     *
+     * @return {@code true} if there is currently a group-by active,
+     *          otherwise returns {@code false}.
      */
     public boolean isCurrentGroup() {
         return currentGroupByExprData != null;
@@ -273,7 +283,7 @@ public abstract class SelectGroups {
      *
      * @param expr
      *            expression
-     * @param object
+     * @param obj
      *            expression data to set
      */
     public final void setCurrentGroupExprData(Expression expr, Object obj) {
@@ -292,6 +302,11 @@ public abstract class SelectGroups {
         currentGroupByExprData[index] = obj;
     }
 
+    /**
+     * Creates new object arrays to holds group-by data.
+     *
+     * @return new object array to holds group-by data.
+     */
     final Object[] createRow() {
         return new Object[Math.max(exprToIndexInGroupByData.size(), expressions.size())];
     }
@@ -321,7 +336,7 @@ public abstract class SelectGroups {
      *            expression
      * @param partitionKey
      *            a key of partition
-     * @param object
+     * @param obj
      *            window expression data to set
      */
     public final void setWindowExprData(DataAnalysisOperation expr, Value partitionKey, PartitionData obj) {
@@ -338,6 +353,9 @@ public abstract class SelectGroups {
         }
     }
 
+    /**
+     * Update group-by data specified by implementation.
+     */
     abstract void updateCurrentGroupExprData();
 
     /**
@@ -412,4 +430,10 @@ public abstract class SelectGroups {
         currentGroupRowId++;
     }
 
+    /**
+     * @return Expressions.
+     */
+    public ArrayList<Expression> expressions() {
+        return expressions;
+    }
 }

h2/src/main/org/h2/engine/OnExitDatabaseCloser.java

@@ -22,6 +22,11 @@ class OnExitDatabaseCloser extends Thread {
 
     private static boolean terminated;
 
+    /**
+     * Register database instance to close one on the JVM process shutdown.
+     *
+     * @param db Database instance.
+     */
     static synchronized void register(Database db) {
         if (terminated) {
             // Shutdown in progress
@@ -46,6 +51,11 @@ class OnExitDatabaseCloser extends Thread {
         }
     }
 
+    /**
+     * Unregister database instance.
+     *
+     * @param db Database instance.
+     */
     static synchronized void unregister(Database db) {
         if (terminated) {
             // Shutdown in progress, do nothing

h2/src/main/org/h2/engine/Session.java

@@ -34,7 +34,7 @@ import org.h2.mvstore.db.MVTable;
 import org.h2.mvstore.db.MVTableEngine;
 import org.h2.mvstore.tx.Transaction;
 import org.h2.mvstore.tx.TransactionStore;
-import org.h2.mvstore.tx.VersionedValue;
+import org.h2.value.VersionedValue;
 import org.h2.result.ResultInterface;
 import org.h2.result.Row;
 import org.h2.result.SortOrder;
@@ -1830,7 +1830,7 @@ public class Session extends SessionWithState implements TransactionStore.Rollba
 
     private static Row getRowFromVersionedValue(MVTable table, long recKey,
                                                 VersionedValue versionedValue) {
-        Object value = versionedValue == null ? null : versionedValue.value;
+        Object value = versionedValue == null ? null : versionedValue.getCurrentValue();
         if (value == null) {
             return null;
         }

h2/src/main/org/h2/expression/condition/ConditionInParameter.java

@@ -65,6 +65,14 @@ public class ConditionInParameter extends Condition {
 
     private final Parameter parameter;
 
+    /**
+     * Gets evaluated condition value.
+     *
+     * @param database database instance.
+     * @param l left value.
+     * @param value parameter value.
+     * @return Evaluated condition value.
+     */
     static Value getValue(Database database, Value l, Value value) {
         boolean hasNull = false;
         if (value.containsNull()) {

h2/src/main/org/h2/jdbc/JdbcLob.java

@@ -69,8 +69,19 @@ public abstract class JdbcLob extends TraceObject {
         CLOSED;
     }
 
+    /**
+     * JDBC connection.
+     */
     final JdbcConnection conn;
+
+    /**
+     * Value.
+     */
     Value value;
+
+    /**
+     * State.
+     */
     State state;
 
     JdbcLob(JdbcConnection conn, Value value, State state, int type, int id) {
@@ -80,6 +91,10 @@ public abstract class JdbcLob extends TraceObject {
         this.state = state;
     }
 
+    /**
+     * Check that connection and LOB is not closed, otherwise throws exception with
+     * error code {@link org.h2.api.ErrorCode#OBJECT_CLOSED}.
+     */
     void checkClosed() {
         conn.checkClosed();
         if (state == State.CLOSED) {
@@ -87,6 +102,10 @@ public abstract class JdbcLob extends TraceObject {
         }
     }
 
+    /**
+     * Check the state of the LOB and throws the exception when check failed
+     * (set is supported only for a new LOB).
+     */
     void checkEditable() {
         checkClosed();
         if (state != State.NEW) {
@@ -94,6 +113,10 @@ public abstract class JdbcLob extends TraceObject {
         }
     }
 
+    /**
+     * Check the state of the LOB and throws the exception when check failed
+     * (the LOB must be set completely before read).
+     */
     void checkReadable() throws SQLException, IOException {
         checkClosed();
         if (state == State.SET_CALLED) {
@@ -101,6 +124,10 @@ public abstract class JdbcLob extends TraceObject {
         }
     }
 
+    /**
+     * Change the state LOB state (LOB value is set completely and available to read).
+     * @param blob LOB value.
+     */
     void completeWrite(Value blob) {
         checkClosed();
         state = State.WITH_VALUE;
@@ -146,10 +173,22 @@ public abstract class JdbcLob extends TraceObject {
         }
     }
 
+    /**
+     * Returns the writer.
+     *
+     * @return Writer.
+     * @throws IOException If an I/O error occurs.
+     */
     Writer setCharacterStreamImpl() throws IOException {
         return IOUtils.getBufferedWriter(setClobOutputStreamImpl());
     }
 
+    /**
+     * Returns the writer stream.
+     *
+     * @return Output stream..
+     * @throws IOException If an I/O error occurs.
+     */
     LobPipedOutputStream setClobOutputStreamImpl() throws IOException {
         // PipedReader / PipedWriter are a lot slower
         // than PipedInputStream / PipedOutputStream

h2/src/main/org/h2/jdbc/JdbcResultSet.java

@@ -3606,7 +3606,7 @@ public class JdbcResultSet extends TraceObject implements ResultSet, JdbcResultS
      * Updates a column in the current or insert row.
      *
      * @param columnIndex (1,2,...)
-     * @param x the value
+     * @param xmlObject the value
      * @throws SQLException if the result set is closed or not updatable
      */
     @Override
@@ -3633,7 +3633,7 @@ public class JdbcResultSet extends TraceObject implements ResultSet, JdbcResultS
      * Updates a column in the current or insert row.
      *
      * @param columnLabel the column label
-     * @param x the value
+     * @param xmlObject the value
      * @throws SQLException if the result set is closed or not updatable
      */
     @Override

h2/src/main/org/h2/message/DbException.java

@@ -55,6 +55,10 @@ public class DbException extends RuntimeException {
 
     private static final Properties MESSAGES = new Properties();
 
+    /**
+     * Thrown when OOME exception is happened on handle error
+     * inside {@link #convert(java.lang.Throwable)}.
+     */
     public static final SQLException SQL_OOME =
             new SQLException("OutOfMemoryError", "HY000", OUT_OF_MEMORY, new OutOfMemoryError());
     private static final DbException OOME = new DbException(SQL_OOME);
@@ -432,6 +436,7 @@ public class DbException extends RuntimeException {
      * @param errorCode the error code
      * @param cause the exception that was the reason for this exception
      * @param stackTrace the stack trace
+     * @return the SQLException object
      */
     public static SQLException getJdbcSQLException(String message, String sql, String state, int errorCode,
             Throwable cause, String stackTrace) {

h2/src/main/org/h2/mvstore/DataUtils.java

@@ -252,6 +252,7 @@ public final class DataUtils {
      *
      * @param out the output stream
      * @param x the value
+     * @throws IOException if some data could not be written
      */
     public static void writeVarInt(OutputStream out, int x) throws IOException {
         while ((x & ~0x7f) != 0) {
@@ -341,6 +342,7 @@ public final class DataUtils {
      *
      * @param out the output stream
      * @param x the value
+     * @throws IOException if some data could not be written
      */
     public static void writeVarLong(OutputStream out, long x)
             throws IOException {

h2/src/main/org/h2/mvstore/MVMap.java

@@ -156,6 +156,7 @@ public class MVMap<K, V> extends AbstractMap<K, V>
      *
      * @param key the key (may not be null)
      * @param value the value (may not be null)
+     * @param decisionMaker callback object for update logic
      * @return the old value if the key existed, or null otherwise
      */
     public final V put(K key, V value, DecisionMaker<? super V> decisionMaker) {
@@ -877,6 +878,9 @@ public class MVMap<K, V> extends AbstractMap<K, V>
      * @param oldRoot the old root reference, will use the current root reference,
      *                if null is specified
      * @param newRoot the new root page
+     * @param attemptUpdateCounter how many attempt (including current)
+     *                             were made to update root
+     * @return new RootReference or null if update failed
      */
     protected final boolean updateRoot(RootReference oldRoot, Page newRoot, int attemptUpdateCounter) {
         return setNewRoot(oldRoot, newRoot, attemptUpdateCounter, true) != null;

h2/src/main/org/h2/mvstore/MVStore.java

@@ -474,6 +474,7 @@ public class MVStore implements AutoCloseable {
      * does not yet exist. If a map with this name is already open, this map is
      * returned.
      *
+     * @param <M> the map type
      * @param <K> the key type
      * @param <V> the value type
      * @param name the name of the map
@@ -1386,7 +1387,7 @@ public class MVStore implements AutoCloseable {
     }
 
     /**
-     * Collect ids for chunks that are no longer in use.
+     * Collect ids for chunks that are in use.
      * @param fast if true, simplified version is used, which assumes that recent chunks
      *            are still in-use and do not scan recent versions of the store.
      *            Also is this case only oldest available version of the store is scanned.

h2/src/main/org/h2/mvstore/StreamStore.java

@@ -95,6 +95,7 @@ public class StreamStore {
      *
      * @param in the stream
      * @return the id (potentially an empty array)
+     * @throws IOException If an I/O error occurs
      */
     @SuppressWarnings("resource")
     public byte[] put(InputStream in) throws IOException {

h2/src/main/org/h2/mvstore/db/MVSpatialIndex.java

@@ -28,7 +28,8 @@ import org.h2.mvstore.rtree.MVRTreeMap.RTreeCursor;
 import org.h2.mvstore.rtree.SpatialKey;
 import org.h2.mvstore.tx.Transaction;
 import org.h2.mvstore.tx.TransactionMap;
-import org.h2.mvstore.tx.VersionedValue;
+import org.h2.mvstore.tx.VersionedValueType;
+import org.h2.value.VersionedValue;
 import org.h2.result.Row;
 import org.h2.result.SearchRow;
 import org.h2.result.SortOrder;
@@ -98,7 +99,7 @@ public class MVSpatialIndex extends BaseIndex implements SpatialIndex, MVIndex {
         }
         String mapName = "index." + getId();
         ValueDataType vt = new ValueDataType(db, null);
-        VersionedValue.Type valueType = new VersionedValue.Type(vt);
+        VersionedValueType valueType = new VersionedValueType(vt);
         MVRTreeMap.Builder<VersionedValue> mapBuilder =
                 new MVRTreeMap.Builder<VersionedValue>().
                 valueType(valueType);

h2/src/main/org/h2/mvstore/tx/CommitDecisionMaker.java

@@ -6,6 +6,7 @@
 package org.h2.mvstore.tx;
 
 import org.h2.mvstore.MVMap;
+import org.h2.value.VersionedValue;
 
 /**
  * Class CommitDecisionMaker makes a decision during post-commit processing
@@ -36,7 +37,7 @@ final class CommitDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
             // see TxDecisionMaker.decide()
 
             decision = MVMap.Decision.ABORT;
-        } else /* this is final undo log entry for this key */ if (existingValue.value == null) {
+        } else /* this is final undo log entry for this key */ if (existingValue.getCurrentValue() == null) {
             decision = MVMap.Decision.REMOVE;
         } else {
             decision = MVMap.Decision.PUT;
@@ -49,7 +50,7 @@ final class CommitDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
     public VersionedValue selectValue(VersionedValue existingValue, VersionedValue providedValue) {
         assert decision == MVMap.Decision.PUT;
         assert existingValue != null;
-        return VersionedValue.getInstance(existingValue.value);
+        return VersionedValueCommitted.getInstance(existingValue.getCurrentValue());
     }
 
     @Override

h2/src/main/org/h2/mvstore/tx/RollbackDecisionMaker.java

@@ -6,6 +6,7 @@
 package org.h2.mvstore.tx;
 
 import org.h2.mvstore.MVMap;
+import org.h2.value.VersionedValue;
 
 /**
  * Class RollbackDecisionMaker process undo log record during transaction rollback.

h2/src/main/org/h2/mvstore/tx/Transaction.java

@@ -9,6 +9,7 @@ import org.h2.mvstore.DataUtils;
 import org.h2.mvstore.MVMap;
 import org.h2.mvstore.MVStore;
 import org.h2.mvstore.type.DataType;
+import org.h2.value.VersionedValue;
 import java.util.Iterator;
 import java.util.concurrent.atomic.AtomicLong;
 
@@ -561,6 +562,8 @@ public class Transaction {
     /**
      * Remove the map.
      *
+     * @param <K> the key type
+     * @param <V> the value type
      * @param map the map
      */
     public <K, V> void removeMap(TransactionMap<K, V> map) {

h2/src/main/org/h2/mvstore/tx/TransactionMap.java

@@ -10,6 +10,7 @@ import org.h2.mvstore.DataUtils;
 import org.h2.mvstore.MVMap;
 import org.h2.mvstore.Page;
 import org.h2.mvstore.type.DataType;
+import org.h2.value.VersionedValue;
 
 import java.util.AbstractMap;
 import java.util.AbstractSet;
@@ -146,7 +147,7 @@ public class TransactionMap<K, V> extends AbstractMap<K, V> {
                     int txId = TransactionStore.getTransactionId(operationId);
                     boolean isVisible = txId == transaction.transactionId ||
                                             committingTransactions.get(txId);
-                    Object v = isVisible ? currentValue.value : currentValue.getCommittedValue();
+                    Object v = isVisible ? currentValue.getCurrentValue() : currentValue.getCommittedValue();
                     if (v == null) {
                         --size;
                     }
@@ -177,7 +178,7 @@ public class TransactionMap<K, V> extends AbstractMap<K, V> {
                                     int txId = TransactionStore.getTransactionId(operationId);
                                     boolean isVisible = txId == transaction.transactionId ||
                                             committingTransactions.get(txId);
-                                    Object v = isVisible ? currentValue.value : currentValue.getCommittedValue();
+                                    Object v = isVisible ? currentValue.getCurrentValue() : currentValue.getCommittedValue();
                                     if (v == null) {
                                         --size;
                                     }
@@ -274,10 +275,10 @@ public class TransactionMap<K, V> extends AbstractMap<K, V> {
      */
     public V putCommitted(K key, V value) {
         DataUtils.checkArgument(value != null, "The value may not be null");
-        VersionedValue newValue = VersionedValue.getInstance(value);
+        VersionedValue newValue = VersionedValueCommitted.getInstance(value);
         VersionedValue oldValue = map.put(key, newValue);
         @SuppressWarnings("unchecked")
-        V result = (V) (oldValue == null ? null : oldValue.value);
+        V result = (V) (oldValue == null ? null : oldValue.getCurrentValue());
         return result;
     }
 
@@ -308,7 +309,7 @@ public class TransactionMap<K, V> extends AbstractMap<K, V> {
             blockingTransaction = decisionMaker.getBlockingTransaction();
             if (decision != MVMap.Decision.ABORT || blockingTransaction == null) {
                 @SuppressWarnings("unchecked")
-                V res = result == null ? null : (V) result.value;
+                V res = result == null ? null : (V) result.getCurrentValue();
                 return res;
             }
             decisionMaker.reset();
@@ -389,12 +390,12 @@ public class TransactionMap<K, V> extends AbstractMap<K, V> {
         long id = data.getOperationId();
         if (id == 0) {
             // it is committed
-            return (V)data.value;
+            return (V)data.getCurrentValue();
         }
         int tx = TransactionStore.getTransactionId(id);
         if (tx == transaction.transactionId || transaction.store.committingTransactions.get().get(tx)) {
             // added by this transaction or another transaction which is committed by now
-            return (V)data.value;
+            return (V) data.getCurrentValue();
         } else {
             return (V) data.getCommittedValue();
         }
@@ -663,7 +664,7 @@ public class TransactionMap<K, V> extends AbstractMap<K, V> {
         @Override
         @SuppressWarnings("unchecked")
         protected Map.Entry<K, V> registerCurrent(K key, VersionedValue data) {
-            return new AbstractMap.SimpleImmutableEntry<>(key, (V) data.value);
+            return new AbstractMap.SimpleImmutableEntry<>(key, (V) data.getCurrentValue());
         }
     }
 
@@ -718,12 +719,12 @@ public class TransactionMap<K, V> extends AbstractMap<K, V> {
                                 // current value comes from another uncommitted transaction
                                 // take committed value instead
                                 Object committedValue = data.getCommittedValue();
-                                data = committedValue == null ? null : VersionedValue.getInstance(committedValue);
+                                data = committedValue == null ? null : VersionedValueCommitted.getInstance(committedValue);
                             }
                         }
                     }
                 }
-                if (data != null && (data.value != null ||
+                if (data != null && (data.getCurrentValue() != null ||
                         includeAllUncommitted && transactionId !=
                                                     TransactionStore.getTransactionId(data.getOperationId()))) {
                     current = registerCurrent(key, data);

h2/src/main/org/h2/mvstore/tx/TransactionStore.java

@@ -20,6 +20,7 @@ import org.h2.mvstore.WriteBuffer;
 import org.h2.mvstore.type.DataType;
 import org.h2.mvstore.type.ObjectDataType;
 import org.h2.util.StringUtils;
+import org.h2.value.VersionedValue;
 
 /**
  * A store that supports concurrent MVCC read-committed transactions.
@@ -128,14 +129,14 @@ public class TransactionStore {
         this.timeoutMillis = timeoutMillis;
         preparedTransactions = store.openMap("openTransactions",
                 new MVMap.Builder<Integer, Object[]>());
-        DataType oldValueType = new VersionedValue.Type(dataType);
+        DataType oldValueType = new VersionedValueType(dataType);
         ArrayType undoLogValueType = new ArrayType(new DataType[]{
                 new ObjectDataType(), dataType, oldValueType
         });
         undoLogBuilder = new MVMap.Builder<Long, Object[]>()
                 .singleWriter()
                 .valueType(undoLogValueType);
-        DataType vt = new VersionedValue.Type(dataType);
+        DataType vt = new VersionedValueType(dataType);
         mapBuilder = new MVMap.Builder<Object, VersionedValue>()
                             .keyType(dataType).valueType(vt);
     }
@@ -494,7 +495,7 @@ public class TransactionStore {
         if (valueType == null) {
             valueType = new ObjectDataType();
         }
-        VersionedValue.Type vt = new VersionedValue.Type(valueType);
+        VersionedValueType vt = new VersionedValueType(valueType);
         MVMap<K, VersionedValue> map;
         MVMap.Builder<K, VersionedValue> builder =
                 new MVMap.Builder<K, VersionedValue>().
@@ -640,7 +641,7 @@ public class TransactionStore {
                     MVMap<Object, VersionedValue> m = openMap(mapId);
                     if (m != null) { // could be null if map was removed later on
                         VersionedValue oldValue = (VersionedValue) op[2];
-                        current = new Change(m.getName(), op[1], oldValue == null ? null : oldValue.value);
+                        current = new Change(m.getName(), op[1], oldValue == null ? null : oldValue.getCurrentValue());
                         return;
                     }
                 }

h2/src/main/org/h2/mvstore/tx/TxDecisionMaker.java

@@ -6,6 +6,7 @@
 package org.h2.mvstore.tx;
 
 import org.h2.mvstore.MVMap;
+import org.h2.value.VersionedValue;
 
 /**
  * Class TxDecisionMaker.
@@ -47,7 +48,7 @@ abstract class TxDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
             // We assume that we are looking at the final value for this transaction,
             // and if it's not the case, then it will fail later,
             // because a tree root has definitely been changed.
-            logIt(existingValue.value == null ? null : VersionedValue.getInstance(existingValue.value));
+            logIt(existingValue.getCurrentValue() == null ? null : VersionedValueCommitted.getInstance(existingValue.getCurrentValue()));
             decision = MVMap.Decision.PUT;
         } else if (getBlockingTransaction() != null) {
             // this entry comes from a different transaction, and this
@@ -63,7 +64,7 @@ abstract class TxDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
             // was written but not undo log), and will effectively roll it back
             // (just assume committed value and overwrite).
             Object committedValue = existingValue.getCommittedValue();
-            logIt(committedValue == null ? null : VersionedValue.getInstance(committedValue));
+            logIt(committedValue == null ? null : VersionedValueCommitted.getInstance(committedValue));
             decision = MVMap.Decision.PUT;
         } else {
             // transaction has been committed/rolled back and is closed by now, so
@@ -138,7 +139,7 @@ abstract class TxDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
         @SuppressWarnings("unchecked")
         @Override
         public final VersionedValue selectValue(VersionedValue existingValue, VersionedValue providedValue) {
-            return VersionedValue.getInstance(undoKey, value,
+            return VersionedValueUncommitted.getInstance(undoKey, value,
                                                 existingValue == null ? null : existingValue.getCommittedValue());
         }
     }
@@ -163,7 +164,7 @@ abstract class TxDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
                 if (id == 0 // entry is a committed one
                             // or it came from the same transaction
                         || isThisTransaction(blockingId = TransactionStore.getTransactionId(id))) {
-                    if(existingValue.value != null) {
+                    if(existingValue.getCurrentValue() != null) {
                         return setDecision(MVMap.Decision.ABORT);
                     }
                     logIt(existingValue);
@@ -171,7 +172,7 @@ abstract class TxDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
                 } else if (isCommitted(blockingId)) {
                     // entry belongs to a committing transaction
                     // and therefore will be committed soon
-                    if(existingValue.value != null) {
+                    if(existingValue.getCurrentValue() != null) {
                         return setDecision(MVMap.Decision.ABORT);
                     }
                     logIt(null);
@@ -228,8 +229,8 @@ abstract class TxDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
         @SuppressWarnings("unchecked")
         @Override
         public VersionedValue selectValue(VersionedValue existingValue, VersionedValue providedValue) {
-            return VersionedValue.getInstance(undoKey,
-                    existingValue == null ? null : existingValue.value,
+            return VersionedValueUncommitted.getInstance(undoKey,
+                    existingValue == null ? null : existingValue.getCurrentValue(),
                     existingValue == null ? null : existingValue.getCommittedValue());
         }
     }

h2/src/main/org/h2/mvstore/tx/VersionedValue.java

-/*
- * Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
- * and the EPL 1.0 (http://h2database.com/html/license.html).
- * Initial Developer: H2 Group
- */
-package org.h2.mvstore.tx;
-
-import org.h2.engine.Constants;
-import org.h2.mvstore.DataUtils;
-import org.h2.mvstore.WriteBuffer;
-import org.h2.mvstore.type.DataType;
-import java.nio.ByteBuffer;
-
-/**
- * A versioned value (possibly null).
- * It contains current value and latest committed value if current one is uncommitted.
- * Also for uncommitted values it contains operationId - a combination of
- * transactionId and logId.
- */
-public class VersionedValue {
-
-    public static final VersionedValue DUMMY = new VersionedValue(new Object());
-
-    /**
-     * The current value.
-     */
-    public final Object value;
-
-    static VersionedValue getInstance(Object value) {
-        assert value != null;
-        return new VersionedValue(value);
-    }
-
-    public static VersionedValue getInstance(long operationId, Object value, Object committedValue) {
-        return new Uncommitted(operationId, value, committedValue);
-    }
-
-    VersionedValue(Object value) {
-        this.value = value;
-    }
-
-    public boolean isCommitted() {
-        return true;
-    }
-
-    public long getOperationId() {
-        return 0L;
-    }
-
-    public Object getCommittedValue() {
-        return value;
-    }
-
-    @Override
-    public String toString() {
-        return String.valueOf(value);
-    }
-
-    private static class Uncommitted extends VersionedValue
-    {
-        private final long   operationId;
-        private final Object committedValue;
-
-        Uncommitted(long operationId, Object value, Object committedValue) {
-            super(value);
-            assert operationId != 0;
-            this.operationId = operationId;
-            this.committedValue = committedValue;
-        }
-
-        @Override
-        public boolean isCommitted() {
-            return false;
-        }
-
-        @Override
-        public long getOperationId() {
-            return operationId;
-        }
-
-        @Override
-        public Object getCommittedValue() {
-            return committedValue;
-        }
-
-        @Override
-        public String toString() {
-            return super.toString() +
-                    " " + TransactionStore.getTransactionId(operationId) + "/" +
-                    TransactionStore.getLogId(operationId) + " " + committedValue;
-        }
-    }
-
-    /**
-     * The value type for a versioned value.
-     */
-    public static class Type implements DataType {
-
-        private final DataType valueType;
-
-        public Type(DataType valueType) {
-            this.valueType = valueType;
-        }
-
-        @Override
-        public int getMemory(Object obj) {
-            if(obj == null) return 0;
-            VersionedValue v = (VersionedValue) obj;
-            int res = Constants.MEMORY_OBJECT + 8 + 2 * Constants.MEMORY_POINTER +
-                    getValMemory(v.value);
-            if (v.getOperationId() != 0) {
-                res += getValMemory(v.getCommittedValue());
-            }
-            return res;
-        }
-
-        private int getValMemory(Object obj) {
-            return obj == null ? 0 : valueType.getMemory(obj);
-        }
-
-        @Override
-        public int compare(Object aObj, Object bObj) {
-            if (aObj == bObj) {
-                return 0;
-            } else if (aObj == null) {
-                return -1;
-            } else if (bObj == null) {
-                return 1;
-            }
-            VersionedValue a = (VersionedValue) aObj;
-            VersionedValue b = (VersionedValue) bObj;
-            long comp = a.getOperationId() - b.getOperationId();
-            if (comp == 0) {
-                return valueType.compare(a.value, b.value);
-            }
-            return Long.signum(comp);
-        }
-
-        @Override
-        public void read(ByteBuffer buff, Object[] obj, int len, boolean key) {
-            if (buff.get() == 0) {
-                // fast path (no op ids or null entries)
-                for (int i = 0; i < len; i++) {
-                    obj[i] = new VersionedValue(valueType.read(buff));
-                }
-            } else {
-                // slow path (some entries may be null)
-                for (int i = 0; i < len; i++) {
-                    obj[i] = read(buff);
-                }
-            }
-        }
-
-        @Override
-        public Object read(ByteBuffer buff) {
-            long operationId = DataUtils.readVarLong(buff);
-            if (operationId == 0) {
-                return new VersionedValue(valueType.read(buff));
-            } else {
-                byte flags = buff.get();
-                Object value = (flags & 1) != 0 ? valueType.read(buff) : null;
-                Object committedValue = (flags & 2) != 0 ? valueType.read(buff) : null;
-                return new Uncommitted(operationId, value, committedValue);
-            }
-        }
-
-        @Override
-        public void write(WriteBuffer buff, Object[] obj, int len, boolean key) {
-            boolean fastPath = true;
-            for (int i = 0; i < len; i++) {
-                VersionedValue v = (VersionedValue) obj[i];
-                if (v.getOperationId() != 0 || v.value == null) {
-                    fastPath = false;
-                }
-            }
-            if (fastPath) {
-                buff.put((byte) 0);
-                for (int i = 0; i < len; i++) {
-                    VersionedValue v = (VersionedValue) obj[i];
-                    valueType.write(buff, v.value);
-                }
-            } else {
-                // slow path:
-                // store op ids, and some entries may be null
-                buff.put((byte) 1);
-                for (int i = 0; i < len; i++) {
-                    write(buff, obj[i]);
-                }
-            }
-        }
-
-        @Override
-        public void write(WriteBuffer buff, Object obj) {
-            VersionedValue v = (VersionedValue) obj;
-            long operationId = v.getOperationId();
-            buff.putVarLong(operationId);
-            if (operationId == 0) {
-                valueType.write(buff, v.value);
-            } else {
-                Object committedValue = v.getCommittedValue();
-                int flags = (v.value == null ? 0 : 1) | (committedValue == null ? 0 : 2);
-                buff.put((byte) flags);
-                if (v.value != null) {
-                    valueType.write(buff, v.value);
-                }
-                if (committedValue != null) {
-                    valueType.write(buff, committedValue);
-                }
-            }
-        }
-    }
-}

h2/src/main/org/h2/mvstore/tx/VersionedValueCommitted.java

+/*
+ * Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
+ * and the EPL 1.0 (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.mvstore.tx;
+
+import org.h2.value.VersionedValue;
+
+/**
+ * Class CommittedVersionedValue.
+ *
+ * @author <a href='mailto:andrei.tokar@gmail.com'>Andrei Tokar</a>
+ */
+class VersionedValueCommitted extends VersionedValue {
+    /**
+     * The current value.
+     */
+    public final Object value;
+
+    VersionedValueCommitted(Object value) {
+        this.value = value;
+    }
+
+    static VersionedValue getInstance(Object value) {
+        assert value != null;
+        return value instanceof VersionedValue ? (VersionedValue) value : new VersionedValueCommitted(value);
+    }
+
+    public Object getCurrentValue() {
+        return value;
+    }
+
+    public Object getCommittedValue() {
+        return value;
+    }
+
+    @Override
+    public String toString() {
+        return String.valueOf(value);
+    }
+}

h2/src/main/org/h2/mvstore/tx/VersionedValueType.java

+/*
+ * Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
+ * and the EPL 1.0 (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.mvstore.tx;
+
+import org.h2.engine.Constants;
+import org.h2.mvstore.DataUtils;
+import org.h2.mvstore.WriteBuffer;
+import org.h2.mvstore.type.DataType;
+import org.h2.value.VersionedValue;
+import java.nio.ByteBuffer;
+
+/**
+ * The value type for a versioned value.
+ */
+public class VersionedValueType implements DataType {
+
+    private final DataType valueType;
+
+    public VersionedValueType(DataType valueType) {
+        this.valueType = valueType;
+    }
+
+    @Override
+    public int getMemory(Object obj) {
+        if(obj == null) return 0;
+        VersionedValue v = (VersionedValue) obj;
+        int res = Constants.MEMORY_OBJECT + 8 + 2 * Constants.MEMORY_POINTER +
+                getValMemory(v.getCurrentValue());
+        if (v.getOperationId() != 0) {
+            res += getValMemory(v.getCommittedValue());
+        }
+        return res;
+    }
+
+    private int getValMemory(Object obj) {
+        return obj == null ? 0 : valueType.getMemory(obj);
+    }
+
+    @Override
+    public int compare(Object aObj, Object bObj) {
+        if (aObj == bObj) {
+            return 0;
+        } else if (aObj == null) {
+            return -1;
+        } else if (bObj == null) {
+            return 1;
+        }
+        VersionedValue a = (VersionedValue) aObj;
+        VersionedValue b = (VersionedValue) bObj;
+        long comp = a.getOperationId() - b.getOperationId();
+        if (comp == 0) {
+            return valueType.compare(a.getCurrentValue(), b.getCurrentValue());
+        }
+        return Long.signum(comp);
+    }
+
+    @Override
+    public void read(ByteBuffer buff, Object[] obj, int len, boolean key) {
+        if (buff.get() == 0) {
+            // fast path (no op ids or null entries)
+            for (int i = 0; i < len; i++) {
+                obj[i] = VersionedValueCommitted.getInstance(valueType.read(buff));
+            }
+        } else {
+            // slow path (some entries may be null)
+            for (int i = 0; i < len; i++) {
+                obj[i] = read(buff);
+            }
+        }
+    }
+
+    @Override
+    public Object read(ByteBuffer buff) {
+        long operationId = DataUtils.readVarLong(buff);
+        if (operationId == 0) {
+            return VersionedValueCommitted.getInstance(valueType.read(buff));
+        } else {
+            byte flags = buff.get();
+            Object value = (flags & 1) != 0 ? valueType.read(buff) : null;
+            Object committedValue = (flags & 2) != 0 ? valueType.read(buff) : null;
+            return VersionedValueUncommitted.getInstance(operationId, value, committedValue);
+        }
+    }
+
+    @Override
+    public void write(WriteBuffer buff, Object[] obj, int len, boolean key) {
+        boolean fastPath = true;
+        for (int i = 0; i < len; i++) {
+            VersionedValue v = (VersionedValue) obj[i];
+            if (v.getOperationId() != 0 || v.getCurrentValue() == null) {
+                fastPath = false;
+            }
+        }
+        if (fastPath) {
+            buff.put((byte) 0);
+            for (int i = 0; i < len; i++) {
+                VersionedValue v = (VersionedValue) obj[i];
+                valueType.write(buff, v.getCurrentValue());
+            }
+        } else {
+            // slow path:
+            // store op ids, and some entries may be null
+            buff.put((byte) 1);
+            for (int i = 0; i < len; i++) {
+                write(buff, obj[i]);
+            }
+        }
+    }
+
+    @Override
+    public void write(WriteBuffer buff, Object obj) {
+        VersionedValue v = (VersionedValue) obj;
+        long operationId = v.getOperationId();
+        buff.putVarLong(operationId);
+        if (operationId == 0) {
+            valueType.write(buff, v.getCurrentValue());
+        } else {
+            Object committedValue = v.getCommittedValue();
+            int flags = (v.getCurrentValue() == null ? 0 : 1) | (committedValue == null ? 0 : 2);
+            buff.put((byte) flags);
+            if (v.getCurrentValue() != null) {
+                valueType.write(buff, v.getCurrentValue());
+            }
+            if (committedValue != null) {
+                valueType.write(buff, committedValue);
+            }
+        }
+    }
+}

h2/src/main/org/h2/mvstore/tx/VersionedValueUncommitted.java

+/*
+ * Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
+ * and the EPL 1.0 (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.mvstore.tx;
+
+import org.h2.value.VersionedValue;
+
+/**
+ * Class VersionedValueUncommitted.
+ *
+ * @author <a href='mailto:andrei.tokar@gmail.com'>Andrei Tokar</a>
+ */
+class VersionedValueUncommitted extends VersionedValueCommitted {
+    private final long operationId;
+    private final Object committedValue;
+
+    private VersionedValueUncommitted(long operationId, Object value, Object committedValue) {
+        super(value);
+        assert operationId != 0;
+        this.operationId = operationId;
+        this.committedValue = committedValue;
+    }
+
+    static VersionedValue getInstance(long operationId, Object value, Object committedValue) {
+        return new VersionedValueUncommitted(operationId, value, committedValue);
+    }
+
+    @Override
+    public boolean isCommitted() {
+        return false;
+    }
+
+    @Override
+    public long getOperationId() {
+        return operationId;
+    }
+
+    @Override
+    public Object getCommittedValue() {
+        return committedValue;
+    }
+
+    @Override
+    public String toString() {
+        return super.toString() +
+                " " + TransactionStore.getTransactionId(operationId) + "/" +
+                TransactionStore.getLogId(operationId) + " " + committedValue;
+    }
+}

h2/src/main/org/h2/result/SimpleResult.java

@@ -94,16 +94,36 @@ public class SimpleResult implements ResultInterface {
         this.rowId = -1;
     }
 
+    /**
+     * Add column to the result.
+     *
+     * @param alias Column's alias.
+     * @param columnName Column's name.
+     * @param columnType Column's type.
+     * @param columnPrecision Column's  precision.
+     * @param columnScale Column's scale.
+     * @param displaySize Column's display data size.
+     */
     public void addColumn(String alias, String columnName, int columnType, long columnPrecision, int columnScale,
             int displaySize) {
         addColumn(new Column(alias, columnName, columnType, columnPrecision, columnScale, displaySize));
     }
 
+    /**
+     * Add column to the result.
+     *
+     * @param column Column info.
+     */
     void addColumn(Column column) {
         assert rows.isEmpty();
         columns.add(column);
     }
 
+    /**
+     * Add row to result.
+     *
+     * @param values Row's values.
+     */
     public void addRow(Value... values) {
         assert values.length == columns.size();
         rows.add(values);

h2/src/main/org/h2/security/auth/AuthenticationInfo.java

@@ -20,7 +20,7 @@ public class AuthenticationInfo {
     private String realm;
 
     /*
-     * Can be used by authenticator to hold informations
+     * Can be used by authenticator to hold information.
      */
     Object nestedIdentity;
 
@@ -58,14 +58,16 @@ public class AuthenticationInfo {
     }
 
     /**
-     * get nested identity
+     * Gets nested identity.
+     *
+     * @return nested identity object.
      */
     public Object getNestedIdentity() {
         return nestedIdentity;
     }
 
     /**
-     * Method used by authenticators to hold informations about authenticated
+     * Method used by authenticators to hold information about authenticated
      * user
      *
      * @param nestedIdentity
@@ -75,6 +77,9 @@ public class AuthenticationInfo {
         this.nestedIdentity = nestedIdentity;
     }
 
+    /**
+     * Clean authentication data.
+     */
     public void clean() {
         this.password = null;
         this.nestedIdentity = null;

h2/src/main/org/h2/security/auth/Authenticator.java

@@ -16,6 +16,8 @@ public interface Authenticator {
     /**
      * Perform user authentication.
      *
+     * @param authenticationInfo authentication info.
+     * @param database target database instance.
      * @return valid database user or null if user doesn't exists in the
      *         database
      */

h2/src/main/org/h2/security/auth/AuthenticatorFactory.java

@@ -10,6 +10,10 @@ package org.h2.security.auth;
  */
 public class AuthenticatorFactory {
 
+    /**
+     * Factory method.
+     * @return authenticator instance.
+     */
     public static Authenticator createAuthenticator() {
         return DefaultAuthenticator.getInstance();
     }

h2/src/main/org/h2/security/auth/ConfigProperties.java

@@ -38,6 +38,13 @@ public class ConfigProperties {
         }
     }
 
+    /**
+     * Returns the string value of specified property.
+     *
+     * @param name property name.
+     * @param defaultValue default value.
+     * @return the string property value or {@code defaultValue} if the property is missing.
+     */
     public String getStringValue(String name, String defaultValue) {
         String result = properties.get(name);
         if (result == null) {
@@ -46,6 +53,13 @@ public class ConfigProperties {
         return result;
     }
 
+    /**
+     * Returns the string value of specified property.
+     *
+     * @param name property name.
+     * @return the string property value.
+     * @throws AuthConfigException if the property is missing.
+     */
     public String getStringValue(String name) {
         String result = properties.get(name);
         if (result == null) {
@@ -54,6 +68,13 @@ public class ConfigProperties {
         return result;
     }
 
+    /**
+     * Returns the integer value of specified property.
+     *
+     * @param name property name.
+     * @param defaultValue default value.
+     * @return the integer property value or {@code defaultValue} if the property is missing.
+     */
     public int getIntValue(String name, int defaultValue) {
         String result = properties.get(name);
         if (result == null) {
@@ -62,6 +83,13 @@ public class ConfigProperties {
         return Integer.parseInt(result);
     }
 
+    /**
+     * Returns the integer value of specified property.
+     *
+     * @param name property name.
+     * @return the integer property value.
+     * @throws AuthConfigException if the property is missing.
+     */
     public int getIntValue(String name) {
         String result = properties.get(name);
         if (result == null) {
@@ -70,6 +98,13 @@ public class ConfigProperties {
         return Integer.parseInt(result);
     }
 
+    /**
+     * Returns the boolean value of specified property.
+     *
+     * @param name property name.
+     * @param defaultValue default value.
+     * @return the boolean property value or {@code defaultValue} if the property is missing.
+     */
     public boolean getBooleanValue(String name, boolean defaultValue) {
         String result = properties.get(name);
         if (result == null) {

h2/src/main/org/h2/security/auth/DefaultAuthenticator.java

@@ -54,19 +54,12 @@ public class DefaultAuthenticator implements Authenticator {
     public static final String DEFAULT_REALMNAME = "H2";
 
     private Map<String, CredentialsValidator> realms = new HashMap<>();
-
     private List<UserToRolesMapper> userToRolesMappers = new ArrayList<>();
-
     private boolean allowUserRegistration;
-
     private boolean persistUsers;
-
     private boolean createMissingRoles;
-
     private boolean skipDefaultInitialization;
-
     private boolean initialized;
-
     private static DefaultAuthenticator instance;
 
     protected static final DefaultAuthenticator getInstance() {
@@ -95,34 +88,62 @@ public class DefaultAuthenticator implements Authenticator {
 
     /**
      * If set save users externals defined during the authentication.
+     *
+     * @return {@code true} if user will be persisted,
+     *      otherwise returns {@code false}
      */
     public boolean isPersistUsers() {
         return persistUsers;
     }
 
+    /**
+     * If set to {@code true} saves users externals defined during the authentication.
+     *
+     * @param persistUsers {@code true} if user will be persisted,
+     *      otherwise {@code false}.
+     */
     public void setPersistUsers(boolean persistUsers) {
         this.persistUsers = persistUsers;
     }
 
     /**
      * If set create external users in the database if not present.
+     *
+     * @return {@code true} if creation external user is allowed,
+     *      otherwise returns {@code false}
      */
     public boolean isAllowUserRegistration() {
         return allowUserRegistration;
     }
 
+    /**
+     * If set to{@code true} creates external users in the database if not present.
+     *
+     * @param allowUserRegistration {@code true} if creation external user is allowed,
+     *      otherwise returns {@code false}
+     */
     public void setAllowUserRegistration(boolean allowUserRegistration) {
         this.allowUserRegistration = allowUserRegistration;
     }
 
     /**
      * When set create roles not found in the database. If not set roles not
-     * found in the database are silently skipped
+     * found in the database are silently skipped.
+     *
+     * @return {@code true} if not found roles will be created,
+     *      {@code false} roles are silently skipped.
      */
     public boolean isCreateMissingRoles() {
         return createMissingRoles;
     }
 
+    /**
+     * Sets the flag that define behavior in case external roles not found in the database.
+     *
+     *
+     * @param createMissingRoles when is {@code true} not found roles are created,
+     *      when is {@code false} roles are silently skipped.
+     */
     public void setCreateMissingRoles(boolean createMissingRoles) {
         this.createMissingRoles = createMissingRoles;
     }
@@ -209,7 +230,7 @@ public class DefaultAuthenticator implements Authenticator {
         }
     }
 
-    void defaultConfiguration() {
+    private void defaultConfiguration() {
         createMissingRoles = false;
         allowUserRegistration = true;
         realms = new HashMap<>();
@@ -232,7 +253,7 @@ public class DefaultAuthenticator implements Authenticator {
         configureFrom(config);
     }
 
-    void configureFrom(H2AuthConfig config) throws AuthenticationException {
+    private void configureFrom(H2AuthConfig config) throws AuthenticationException {
         allowUserRegistration = config.isAllowUserRegistration();
         createMissingRoles = config.isCreateMissingRoles();
         Map<String, CredentialsValidator> newRealms = new HashMap<>();
@@ -270,7 +291,7 @@ public class DefaultAuthenticator implements Authenticator {
         this.userToRolesMappers = newUserToRolesMapper;
     }
 
-    boolean updateRoles(AuthenticationInfo authenticationInfo, User user, Database database)
+    private boolean updateRoles(AuthenticationInfo authenticationInfo, User user, Database database)
             throws AuthenticationException {
         boolean updatedDb = false;
         Set<String> roles = new HashSet<>();

h2/src/main/org/h2/security/auth/H2AuthConfig.java

@@ -9,32 +9,56 @@ import java.util.ArrayList;
 import java.util.List;
 
 /**
- * Describe configuration of H2 DefaultAuthenticator
+ * Describe configuration of H2 DefaultAuthenticator.
  */
 public class H2AuthConfig {
 
     private boolean allowUserRegistration=true;
+    private boolean createMissingRoles=true;
+    private List<RealmConfig> realms;
+    private List<UserToRolesMapperConfig> userToRolesMappers;
 
+    /**
+     * Allow user registration flag. If set to {@code true}
+     * creates external users in the database if not present.
+     *
+     * @return {@code true} in case user registration is allowed,
+     *          otherwise returns {@code false}.
+     */
     public boolean isAllowUserRegistration() {
         return allowUserRegistration;
     }
 
+    /**
+     * @param allowUserRegistration Allow user registration flag.
+     */
     public void setAllowUserRegistration(boolean allowUserRegistration) {
         this.allowUserRegistration = allowUserRegistration;
     }
 
-    boolean createMissingRoles=true;
-
+    /**
+     * When set create roles not found in the database. If not set roles not
+     * found in the database are silently skipped.
+     * @return {@code true} if the flag is set, otherwise returns {@code false}.
+     */
     public boolean isCreateMissingRoles() {
         return createMissingRoles;
     }
 
+    /**
+     * When set create roles not found in the database. If not set roles not
+     * found in the database are silently skipped
+     * @param createMissingRoles missing roles flag.
+     */
     public void setCreateMissingRoles(boolean createMissingRoles) {
         this.createMissingRoles = createMissingRoles;
     }
 
-    List<RealmConfig> realms;
-
+    /**
+     * Gets configuration of authentication realms.
+     *
+     * @return configuration of authentication realms.
+     */
     public List<RealmConfig> getRealms() {
         if (realms == null) {
             realms = new ArrayList<>();
@@ -42,12 +66,20 @@ public class H2AuthConfig {
         return realms;
     }
 
+    /**
+     * Sets configuration of authentication realms.
+     *
+     * @param realms configuration of authentication realms.
+     */
     public void setRealms(List<RealmConfig> realms) {
         this.realms = realms;
     }
 
-    List<UserToRolesMapperConfig> userToRolesMappers;
-
+    /**
+     * Gets configuration of the mappers external users to database roles.
+     *
+     * @return configuration of the mappers external users to database roles.
+     */
     public List<UserToRolesMapperConfig> getUserToRolesMappers() {
         if (userToRolesMappers == null) {
             userToRolesMappers = new ArrayList<>();
@@ -55,6 +87,11 @@ public class H2AuthConfig {
         return userToRolesMappers;
     }
 
+    /**
+     * Sets configuration of the mappers external users to database roles.
+     *
+     * @param userToRolesMappers configuration of the mappers external users to database roles.
+     */
     public void setUserToRolesMappers(List<UserToRolesMapperConfig> userToRolesMappers) {
         this.userToRolesMappers = userToRolesMappers;
     }

h2/src/main/org/h2/security/auth/H2AuthConfigXml.java

@@ -20,9 +20,8 @@ import org.xml.sax.helpers.DefaultHandler;
  */
 public class H2AuthConfigXml extends DefaultHandler{
 
-    H2AuthConfig result;
-
-    HasConfigProperties lastConfigProperties;
+    private H2AuthConfig result;
+    private HasConfigProperties lastConfigProperties;
 
     @Override
     public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
@@ -68,7 +67,7 @@ public class H2AuthConfigXml extends DefaultHandler{
         }
     }
 
-    static String getMandatoryAttributeValue(String attributeName, Attributes attributes) throws SAXException {
+    private static String getMandatoryAttributeValue(String attributeName, Attributes attributes) throws SAXException {
         String attributeValue=attributes.getValue(attributeName);
         if (attributeValue==null || attributeValue.trim().equals("")) {
             throw new SAXException("missing attribute "+attributeName);
@@ -77,7 +76,7 @@ public class H2AuthConfigXml extends DefaultHandler{
 
     }
 
-    static String getAttributeValueOr(String attributeName, Attributes attributes, String defaultValue) {
+    private static String getAttributeValueOr(String attributeName, Attributes attributes, String defaultValue) {
         String attributeValue=attributes.getValue(attributeName);
         if (attributeValue==null || attributeValue.trim().equals("")) {
             return defaultValue;
@@ -85,12 +84,23 @@ public class H2AuthConfigXml extends DefaultHandler{
         return attributeValue;
     }
 
+    /**
+     * Returns parsed authenticator configuration.
+     *
+     * @return Authenticator configuration.
+     */
     public H2AuthConfig getResult() {
         return result;
     }
 
     /**
-     * Parse the xml
+     * Parse the xml.
+     *
+     * @param url the source of the xml configuration.
+     * @return Authenticator configuration.
+     * @throws ParserConfigurationException if a parser cannot be created.
+     * @throws SAXException for SAX errors.
+     * @throws IOException If an I/O error occurs
      */
     public static H2AuthConfig parseFrom(URL url)
             throws SAXException, IOException, ParserConfigurationException {
@@ -99,6 +109,15 @@ public class H2AuthConfigXml extends DefaultHandler{
         }
     }
 
+    /**
+     * Parse the xml.
+     *
+     * @param inputStream the source of the xml configuration.
+     * @return Authenticator configuration.
+     * @throws ParserConfigurationException if a parser cannot be created.
+     * @throws SAXException for SAX errors.
+     * @throws IOException If an I/O error occurs
+     */
     public static H2AuthConfig parseFrom(InputStream inputStream)
             throws SAXException, IOException, ParserConfigurationException {
         SAXParser saxParser = SAXParserFactory.newInstance().newSAXParser();

h2/src/main/org/h2/security/auth/RealmConfig.java

@@ -14,27 +14,45 @@ import java.util.List;
 public class RealmConfig implements HasConfigProperties {
 
     private String name;
+    private String validatorClass;
+    private List<PropertyConfig> properties;
 
+    /**
+     * Gets realm's name.
+     *
+     * @return realm's name.
+     */
     public String getName() {
         return name;
     }
 
+    /**
+     * Sets realm's name.
+     *
+     * @param name realm's name.
+     */
     public void setName(String name) {
         this.name = name;
     }
 
-    String validatorClass;
-
+    /**
+     * Gets validator class name.
+     *
+     * @return validator class name.
+     */
     public String getValidatorClass() {
         return validatorClass;
     }
 
+    /**
+     * Sets validator class name.
+     *
+     * @param  validatorClass validator class name.
+     */
     public void setValidatorClass(String validatorClass) {
         this.validatorClass = validatorClass;
     }
 
-    List<PropertyConfig> properties;
-
     @Override
     public List<PropertyConfig> getProperties() {
         if (properties == null) {

h2/src/main/org/h2/security/auth/UserToRolesMapperConfig.java

@@ -10,21 +10,31 @@ import java.util.List;
 
 /**
  * Configuration for class that maps users to their roles.
+ *
+ * @see org.h2.api.UserToRolesMapper
  */
 public class UserToRolesMapperConfig implements HasConfigProperties {
 
     private String className;
-
     private List<PropertyConfig> properties;
 
+    /**
+     * @return Mapper class name.
+     */
     public String getClassName() {
         return className;
     }
 
+    /**
+     * @param className mapper class name.
+     */
     public void setClassName(String className) {
         this.className = className;
     }
 
+    /**
+     * @return Mapper properties.
+     */
     @Override
     public List<PropertyConfig> getProperties() {
         if (properties == null) {

h2/src/main/org/h2/store/fs/FilePath.java

@@ -218,6 +218,7 @@ public abstract class FilePath {
      * @param append if true, the file will grow, if false, the file will be
      *            truncated first
      * @return the output stream
+     * @throws IOException If an I/O error occurs
      */
     public abstract OutputStream newOutputStream(boolean append) throws IOException;
 
@@ -226,6 +227,7 @@ public abstract class FilePath {
      *
      * @param mode the access mode. Supported are r, rw, rws, rwd
      * @return the file object
+     * @throws IOException If an I/O error occurs
      */
     public abstract FileChannel open(String mode) throws IOException;
 
@@ -233,6 +235,7 @@ public abstract class FilePath {
      * Create an input stream to read from the file.
      *
      * @return the input stream
+     * @throws IOException If an I/O error occurs
      */
     public abstract InputStream newInputStream() throws IOException;
 

h2/src/main/org/h2/table/Table.java

@@ -656,6 +656,13 @@ public abstract class Table extends SchemaObjectBase {
         }
     }
 
+    /**
+     * Create a new row for a table.
+     *
+     * @param data the values.
+     * @param memory whether the row is in memory.
+     * @return the created row.
+     */
     public Row createRow(Value[] data, int memory) {
         return database.createRow(data, memory);
     }

h2/src/main/org/h2/util/DateTimeUtils.java

@@ -457,6 +457,14 @@ public class DateTimeUtils {
         return ((((hour * 60L) + minute) * 60) + second) * NANOS_PER_SECOND + nanos;
     }
 
+    /**
+     * Parse nanoseconds.
+     *
+     * @param s String to parse.
+     * @param start Begin position at the string to read.
+     * @param end End position at the string to read.
+     * @return Parsed nanoseconds.
+     */
     static int parseNanos(String s, int start, int end) {
         if (start >= end) {
             throw new IllegalArgumentException(s);
@@ -1230,6 +1238,8 @@ public class DateTimeUtils {
     }
 
     /**
+     * Creates the instance of the {@link ValueTimestampTimeZone} from milliseconds.
+     *
      * @param ms milliseconds since 1970-01-01 (UTC)
      * @return timestamp with time zone with specified value and current time zone
      */
@@ -1473,6 +1483,11 @@ public class DateTimeUtils {
         }
     }
 
+    /**
+     * Skip trailing zeroes.
+     *
+     * @param buff String buffer.
+     */
     static void stripTrailingZeroes(StringBuilder buff) {
         int i = buff.length() - 1;
         if (buff.charAt(i) == '0') {

h2/src/main/org/h2/util/IntervalUtils.java

@@ -665,6 +665,8 @@ public class IntervalUtils {
     }
 
     /**
+     * Returns years value of interval, if any.
+     *
      * @param qualifier
      *            qualifier
      * @param negative
@@ -688,6 +690,8 @@ public class IntervalUtils {
     }
 
     /**
+     * Returns months value of interval, if any.
+     *
      * @param qualifier
      *            qualifier
      * @param negative
@@ -715,6 +719,8 @@ public class IntervalUtils {
     }
 
     /**
+     * Returns days value of interval, if any.
+     *
      * @param qualifier
      *            qualifier
      * @param negative
@@ -723,7 +729,7 @@ public class IntervalUtils {
      *            value of leading field
      * @param remaining
      *            values of all remaining fields
-     * @return months, or 0
+     * @return days, or 0
      */
     public static long daysFromInterval(IntervalQualifier qualifier, boolean negative, long leading, long remaining) {
         switch (qualifier) {
@@ -742,6 +748,8 @@ public class IntervalUtils {
     }
 
     /**
+     * Returns hours value of interval, if any.
+     *
      * @param qualifier
      *            qualifier
      * @param negative
@@ -779,6 +787,8 @@ public class IntervalUtils {
     }
 
     /**
+     * Returns minutes value of interval, if any.
+     *
      * @param qualifier
      *            qualifier
      * @param negative
@@ -819,6 +829,8 @@ public class IntervalUtils {
     }
 
     /**
+     * Returns nanoseconds value of interval, if any.
+     *
      * @param qualifier
      *            qualifier
      * @param negative

h2/src/main/org/h2/util/ValueHashMap.java

@@ -35,7 +35,14 @@ import org.h2.value.ValueNull;
  */
 public class ValueHashMap<V> extends HashBase {
 
+    /**
+     * Keys array.
+     */
     Value[] keys;
+
+    /**
+     * Values array.
+     */
     V[] values;
 
     @Override
@@ -202,6 +209,11 @@ public class ValueHashMap<V> extends HashBase {
         }
     }
 
+    /**
+     * Gets all map's entries.
+     *
+     * @return all map's entries.
+     */
     public Iterable<Map.Entry<Value, V>> entries() {
         return new EntryIterable();
     }

h2/src/main/org/h2/util/geometry/EWKBUtils.java

@@ -269,7 +269,7 @@ public final class EWKBUtils {
      *
      * @param ewkb
      *            source EWKB
-     * @param dimension
+     * @param dimensionSystem
      *            dimension system
      * @return canonical EWKB, may be the same as the source
      */

h2/src/main/org/h2/util/geometry/EWKTUtils.java

@@ -563,7 +563,7 @@ public final class EWKTUtils {
      *
      * @param ewkb
      *            source EWKB
-     * @param dimension
+     * @param dimensionSystem
      *            dimension system
      * @return EWKT representation
      */
@@ -594,7 +594,7 @@ public final class EWKTUtils {
      *
      * @param ewkt
      *            source EWKT
-     * @param dimension
+     * @param dimensionSystem
      *            dimension system
      * @return EWKB representation
      */
@@ -608,7 +608,7 @@ public final class EWKTUtils {
     /**
      * Parses a EWKB.
      *
-     * @param source
+     * @param ewkt
      *            source EWKT
      * @param target
      *            output target

h2/src/main/org/h2/value/Value.java

@@ -40,7 +40,7 @@ import org.h2.util.StringUtils;
  * @author Noel Grandin
  * @author Nicolas Fortin, Atelier SIG, IRSTV FR CNRS 24888
  */
-public abstract class Value {
+public abstract class Value extends VersionedValue {
 
     /**
      * The data type is unknown at this time.
@@ -1347,6 +1347,12 @@ public abstract class Value {
         return ValueResultSet.get(result);
     }
 
+    /**
+     * Creates new instance of the DbException for data conversion error.
+     *
+     * @param targetType Target data type.
+     * @return instance of the DbException.
+     */
     DbException getDataConversionError(int targetType) {
         DataType from = DataType.getDataType(getType());
         DataType to = DataType.getDataType(targetType);
@@ -1489,6 +1495,13 @@ public abstract class Value {
         return (short) x;
     }
 
+    /**
+     * Checks value by Integer type numeric range.
+     *
+     * @param x integer value.
+     * @param column Column info.
+     * @return x
+     */
     public static int convertToInt(long x, Object column) {
         if (x > Integer.MAX_VALUE || x < Integer.MIN_VALUE) {
             throw DbException.get(

h2/src/main/org/h2/value/ValueCollectionBase.java

@@ -16,6 +16,9 @@ import org.h2.util.MathUtils;
  */
 public abstract class ValueCollectionBase extends Value {
 
+    /**
+     * Values.
+     */
     final Value[] values;
 
     private int hash;

h2/src/main/org/h2/value/ValueInterval.java

@@ -53,6 +53,8 @@ public class ValueInterval extends Value {
     private final long remaining;
 
     /**
+     * Creates interval value.
+     *
      * @param qualifier
      *            qualifier
      * @param negative
@@ -80,6 +82,7 @@ public class ValueInterval extends Value {
      * @param scale
      *            fractional seconds precision. Ignored if specified type of
      *            interval does not have seconds.
+     * @return displayed size.
      */
     public static int getDisplaySize(int type, int precision, int scale) {
         switch (type) {

h2/src/main/org/h2/value/VersionedValue.java

+/*
+ * Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
+ * and the EPL 1.0 (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.value;
+
+/**
+ * A versioned value (possibly null).
+ * It contains current value and latest committed value if current one is uncommitted.
+ * Also for uncommitted values it contains operationId - a combination of
+ * transactionId and logId.
+ */
+public class VersionedValue {
+
+    public static final VersionedValue DUMMY = new VersionedValue();
+
+    protected VersionedValue() {}
+
+    public boolean isCommitted() {
+        return true;
+    }
+
+    public long getOperationId() {
+        return 0L;
+    }
+
+    public Object getCurrentValue() {
+        return this;
+    }
+
+    public Object getCommittedValue() {
+        return this;
+    }
+
+}

h2/src/test/org/h2/test/TestAll.java

@@ -440,6 +440,10 @@ java org.h2.test.TestAll timer
 
     private Server server;
 
+    /**
+     * The map of executed tests to detect not executed tests.
+     * Boolean value is 'false' for a disabled test.
+     */
     HashMap<Class<? extends TestBase>, Boolean> executedTests = new HashMap<>();
 
     /**

h2/src/test/org/h2/test/jdbc/TestSQLXML.java

@@ -185,7 +185,7 @@ public class TestSQLXML extends TestDb {
         }
     }
 
-    void testSettersImpl(SQLXML sqlxml) throws SQLException {
+    private void testSettersImpl(SQLXML sqlxml) throws SQLException {
         PreparedStatement prep = conn.prepareStatement("UPDATE TEST SET X = ?");
         prep.setSQLXML(1, sqlxml);
         assertEquals(1, prep.executeUpdate());

h2/src/test/org/h2/test/scripts/TestScript.java

@@ -289,7 +289,7 @@ public class TestScript extends TestDb {
         return s;
     }
 
-    public void putBack(String line) {
+    private void putBack(String line) {
         putBack.addLast(line);
     }
 

h2/src/test/org/h2/test/scripts/dml/select.sql

@@ -466,3 +466,46 @@ DROP TABLE TEST;
 
 SELECT 1 = ALL (SELECT * FROM VALUES (NULL), (1), (2), (NULL) ORDER BY 1);
 >> FALSE
+
+CREATE TABLE TEST(G INT, V INT);
+> ok
+
+INSERT INTO TEST VALUES (10, 1), (11, 2), (20, 4);
+> update count: 3
+
+SELECT G / 10 G1, G / 10 G2, SUM(T.V) S FROM TEST T GROUP BY G / 10, G / 10;
+> G1 G2 S
+> -- -- -
+> 1  1  3
+> 2  2  4
+> rows: 2
+
+
+SELECT G / 10 G1, G / 10 G2, SUM(T.V) S FROM TEST T GROUP BY G2;
+> G1 G2 S
+> -- -- -
+> 1  1  3
+> 2  2  4
+> rows: 2
+
+DROP TABLE TEST;
+> ok
+
+@reconnect off
+
+CALL RAND(0);
+>> 0.730967787376657
+
+SELECT RAND(), RAND() + 1, RAND() + 1, RAND() GROUP BY RAND() + 1;
+> RAND()             RAND() + 1         RAND() + 1         RAND()
+> ------------------ ------------------ ------------------ ------------------
+> 0.6374174253501083 1.2405364156714858 1.2405364156714858 0.5504370051176339
+> rows: 1
+
+SELECT RAND() A, RAND() + 1 B, RAND() + 1 C, RAND() D, RAND() + 2 E, RAND() + 3 F GROUP BY B, C, E, F;
+> A                  B                  C                  D                  E                  F
+> ------------------ ------------------ ------------------ ------------------ ------------------ ------------------
+> 0.8791825178724801 1.3332183994766498 1.3332183994766498 0.9412491794821144 2.3851891847407183 3.9848415401998087
+> rows: 1
+
+@reconnect on

h2/src/test/org/h2/test/unit/TestLocalResultFactory.java

@@ -50,6 +50,7 @@ public class TestLocalResultFactory extends TestBase {
      * Test local result factory.
      */
     public static class MyTestLocalResultFactory extends LocalResultFactory {
+        /** Call counter for the factory methods. */
         static final AtomicInteger COUNTER = new AtomicInteger();
 
         @Override public LocalResult create(Session session, Expression[] expressions, int visibleColumnCount) {

h2/src/test/org/h2/test/unit/TestValue.java

@@ -483,7 +483,7 @@ public class TestValue extends TestDb {
         return lob1.compareTypeSafe(lob2, null);
     }
 
-    static Value createLob(DataHandler dh, int type, byte[] bytes) {
+    private static Value createLob(DataHandler dh, int type, byte[] bytes) {
         if (dh == null) {
             return ValueLobDb.createSmallLob(type, bytes);
         }

h2/src/tools/org/h2/build/Build.java

@@ -668,7 +668,9 @@ public class Build extends BuildBase {
                 File.pathSeparator + "ext/lucene-queryparser-5.5.5.jar" +
                 File.pathSeparator + "ext/org.osgi.core-4.2.0.jar" +
                 File.pathSeparator + "ext/org.osgi.enterprise-4.2.0.jar" +
-                File.pathSeparator + "ext/jts-core-1.15.0.jar",
+                File.pathSeparator + "ext/jts-core-1.15.0.jar" +
+                File.pathSeparator + "ext/asm-6.1.jar" +
+                File.pathSeparator + "ext/junit-4.12.jar",
                 "-subpackages", "org.h2");
 
         mkdir("docs/javadocImpl3");
@@ -701,7 +703,9 @@ public class Build extends BuildBase {
                 File.pathSeparator + "ext/lucene-queryparser-5.5.5.jar" +
                 File.pathSeparator + "ext/org.osgi.core-4.2.0.jar" +
                 File.pathSeparator + "ext/org.osgi.enterprise-4.2.0.jar" +
-                File.pathSeparator + "ext/jts-core-1.15.0.jar",
+                File.pathSeparator + "ext/jts-core-1.15.0.jar" +
+                File.pathSeparator + "ext/asm-6.1.jar" +
+                File.pathSeparator + "ext/junit-4.12.jar",
                 "-subpackages", "org.h2",
                 "-package",
                 "-docletpath", "bin" + File.pathSeparator + "temp",

h2/src/tools/org/h2/build/doc/dictionary.txt

@@ -805,3 +805,4 @@ queryparser tokenized freeze factorings recompilation unenclosed rfe dsync
 econd irst bcef ordinality nord unnest
 analyst occupation distributive josaph aor engineer sajeewa isuru randil kevin doctor businessman artist ashan
 corrupts splitted disruption unintentional octets preconditions predicates subq objectweb insn opcodes
+preserves