MVStore: improved API thanks to Simo Tripodi.

h2/src/docsrc/html/changelog.html

@@ -31,6 +31,7 @@ Change Log
 </li><li>New connection setting "DEFAULT_TABLE_ENGINE" to use a specific
     table engine if none is set explicitly. This is to simplify testing 
     the MVStore table engine.
+</li><li>MVStore: improved API thanks to Simo Tripodi.
 </li><li>MVStore: maps can now be renamed.
 </li><li>MVStore: store the file header also at the end of each chunk,
     which results in a further reduced number of write operations.

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

@@ -557,14 +557,18 @@ public class DataUtils {
         return new IllegalStateException(message + version());
     }
 
-    public static IllegalStateException illegalStateException(String message, Exception e) {
-        return new IllegalStateException(message + version(), e);
+    public static IllegalStateException illegalStateException(String message, Exception cause) {
+        return new IllegalStateException(message + version(), cause);
     }
 
     public static IllegalArgumentException illegalArgumentException(String message) {
         return new IllegalArgumentException(message + version());
     }
 
+    public static IllegalArgumentException illegalArgumentException(String message, Exception cause) {
+        return new IllegalArgumentException(message + version(), cause);
+    }
+
     public static UnsupportedOperationException unsupportedOperationException(String message) {
         return new UnsupportedOperationException(message + version());
     }

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

@@ -17,6 +17,7 @@ import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentMap;
 import org.h2.mvstore.type.DataType;
+import org.h2.mvstore.type.ObjectDataType;
 import org.h2.util.New;
 
 /**
@@ -47,7 +48,7 @@ public class MVMap<K, V> extends AbstractMap<K, V>
     private boolean closed;
     private boolean readOnly;
 
-    public MVMap(DataType keyType, DataType valueType) {
+    protected MVMap(DataType keyType, DataType valueType) {
         this.keyType = keyType;
         this.valueType = valueType;
         this.root = Page.createEmpty(this,  -1);
@@ -1048,4 +1049,76 @@ public class MVMap<K, V> extends AbstractMap<K, V>
         return asString(null);
     }
 
+
+    /**
+     * A builder for maps.
+     *
+     * @param <M> the map type
+     * @param <K> the key type
+     * @param <V> the value type
+     */
+    public interface MapBuilder<M extends MVMap<K, V>, K, V> {
+
+        /**
+         * Create a new map of the given type.
+         *
+         * @return the map
+         */
+        public M create();
+
+    }
+
+    /**
+     * A builder for this class.
+     *
+     * @param <K> the key type
+     * @param <V> the value type
+     */
+    public static class Builder<K, V> implements MapBuilder<MVMap<K, V>, K, V> {
+
+        protected DataType keyType;
+        protected DataType valueType;
+
+        /**
+         * Create a new builder with the default key and value data types.
+         */
+        public Builder() {
+            // ignore
+        }
+
+        /**
+         * Set the key data type.
+         *
+         * @param keyType the key type
+         * @return this
+         */
+        public Builder<K, V> keyType(DataType keyType) {
+            this.keyType = keyType;
+            return this;
+        }
+
+        /**
+         * Set the key data type.
+         *
+         * @param valueType the key type
+         * @return this
+         */
+        public Builder<K, V> valueType(DataType valueType) {
+            this.valueType = valueType;
+            return this;
+        }
+
+        @Override
+        public MVMap<K, V> create() {
+            if (keyType == null) {
+                keyType = new ObjectDataType();
+            }
+            if (valueType == null) {
+                valueType = new ObjectDataType();
+            }
+            return new MVMap<K, V>(keyType, valueType);
+        }
+
+    }
+
 }

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

@@ -69,4 +69,57 @@ public class MVMapConcurrent<K, V> extends MVMap<K, V> {
         return result;
     }
 
+    /**
+     * A builder for this class.
+     *
+     * @param <K> the key type
+     * @param <V> the value type
+     */
+    public static class Builder<K, V> implements MapBuilder<MVMapConcurrent<K, V>, K, V> {
+
+        protected DataType keyType;
+        protected DataType valueType;
+
+        /**
+         * Create a new builder with the default key and value data types.
+         */
+        public Builder() {
+            // ignore
+        }
+
+        /**
+         * Set the key data type.
+         *
+         * @param keyType the key type
+         * @return this
+         */
+        public Builder<K, V> keyType(DataType keyType) {
+            this.keyType = keyType;
+            return this;
+        }
+
+        /**
+         * Set the key data type.
+         *
+         * @param valueType the key type
+         * @return this
+         */
+        public Builder<K, V> valueType(DataType valueType) {
+            this.valueType = valueType;
+            return this;
+        }
+
+        @Override
+        public MVMapConcurrent<K, V> create() {
+            if (keyType == null) {
+                keyType = new ObjectDataType();
+            }
+            if (valueType == null) {
+                valueType = new ObjectDataType();
+            }
+            return new MVMapConcurrent<K, V>(keyType, valueType);
+        }
+
+    }
+
 }

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

@@ -21,7 +21,6 @@ import org.h2.compress.CompressLZF;
 import org.h2.compress.Compressor;
 import org.h2.mvstore.cache.CacheLongKeyLIRS;
 import org.h2.mvstore.cache.FilePathCache;
-import org.h2.mvstore.type.DataType;
 import org.h2.mvstore.type.DataTypeFactory;
 import org.h2.mvstore.type.ObjectDataTypeFactory;
 import org.h2.mvstore.type.StringDataType;
@@ -44,7 +43,8 @@ H:3,...
 
 TODO:
 
-- MVStore: improved API thanks to Simo Tripodi
+- fix MVStore documentation, example code
+- improve exception factory (fluent api)
 - implement table engine for H2
 - automated 'kill process' and 'power failure' test
 - maybe split database into multiple files, to speed up compact
@@ -121,8 +121,6 @@ public class MVStore {
      */
     static final int BLOCK_SIZE = 4 * 1024;
 
-    private final HashMap<String, Object> config;
-
     private final String fileName;
     private final DataTypeFactory dataTypeFactory;
 
@@ -187,7 +185,6 @@ public class MVStore {
     private boolean closed;
 
     MVStore(HashMap<String, Object> config) {
-        this.config = config;
         this.fileName = (String) config.get("fileName");
         DataTypeFactory parent = new ObjectDataTypeFactory();
         DataTypeFactory f = (DataTypeFactory) config.get("dataTypeFactory");
@@ -242,67 +239,49 @@ public class MVStore {
     }
 
     /**
-     * Open a map with the previous key and value type (if the map already
-     * exists), or Object if not.
+     * Open a map with the default settings. The map is automatically create if
+     * it does not yet exist. If a map with this name is already open, this map
+     * is returned.
      *
      * @param <K> the key type
      * @param <V> the value type
      * @param name the name of the map
      * @return the map
      */
-    @SuppressWarnings("unchecked")
     public <K, V> MVMap<K, V> openMap(String name) {
-        return (MVMap<K, V>) openMap(name, Object.class, Object.class);
+        return openMap(name, new MVMap.Builder<K, V>());
     }
 
     /**
-     * Open a map.
+     * Open a map with the given builder. The map is automatically create if it
+     * does not yet exist. If a map with this name is already open, this map is
+     * returned.
      *
      * @param <K> the key type
      * @param <V> the value type
      * @param name the name of the map
-     * @param keyClass the key class
-     * @param valueClass the value class
+     * @param builder the map builder
      * @return the map
      */
-    public <K, V> MVMap<K, V> openMap(String name, Class<K> keyClass, Class<V> valueClass) {
-        checkOpen();
-        DataType keyType = getDataType(keyClass);
-        DataType valueType = getDataType(valueClass);
-        MVMap<K, V> m = new MVMap<K, V>(keyType, valueType);
-        return openMap(name, m);
-    }
-
-    /**
-     * Open a map using the given template. The returned map is of the same type
-     * as the template, and contains the same key and value types. If a map with
-     * this name is already open, this map is returned. If it is not open,
-     * the template object is opened with the applicable configuration.
-     *
-     * @param <T> the map type
-     * @param name the name of the map
-     * @param template the template map
-     * @return the opened map
-     */
-    @SuppressWarnings("unchecked")
-    public <T extends MVMap<K, V>, K, V> T openMap(String name, T template) {
+    public <M extends MVMap<K, V>, K, V> M openMap(String name, MVMap.MapBuilder<M, K, V> builder) {
         checkOpen();
-        MVMap<K, V> m;
         String x = meta.get("name." + name);
         int id;
         long root;
         HashMap<String, String> c;
+        M map;
         if (x != null) {
             id = Integer.parseInt(x);
-            m = (MVMap<K, V>) maps.get(id);
-            if (m != null) {
-                return (T) m;
+            @SuppressWarnings("unchecked")
+            M old = (M) maps.get(id);
+            if (old != null) {
+                return old;
             }
-            m = template;
+            map = builder.create();
             String config = meta.get("map." + x);
             c = DataUtils.parseMap(config);
             c.put("id", x);
-            m.open(this, c);
+            map.open(this, c);
             String r = meta.get("root." + id);
             root = r == null ? 0 : Long.parseLong(r);
         } else {
@@ -310,15 +289,15 @@ public class MVStore {
             id = ++lastMapId;
             c.put("id", Integer.toString(id));
             c.put("createVersion", Long.toString(currentVersion));
-            m = template;
-            m.open(this, c);
-            meta.put("map." + id, m.asString(name));
+            map = builder.create();
+            map.open(this, c);
+            meta.put("map." + id, map.asString(name));
             meta.put("name." + name, Integer.toString(id));
             root = 0;
         }
-        m.setRootPos(root, -1);
-        maps.put(id, m);
-        return (T) m;
+        map.setRootPos(root, -1);
+        maps.put(id, map);
+        return map;
     }
 
     /**
@@ -377,14 +356,6 @@ public class MVStore {
         maps.remove(id);
     }
 
-    private DataType getDataType(Class<?> clazz) {
-        if (clazz == String.class) {
-            return StringDataType.INSTANCE;
-        }
-        String s = dataTypeFactory.getDataType(clazz);
-        return dataTypeFactory.buildDataType(s);
-    }
-
     /**
      * Mark a map as changed (containing unsaved changes).
      *
@@ -1372,10 +1343,6 @@ public class MVStore {
         }
     }
 
-    public String toString() {
-        return DataUtils.appendMap(new StringBuilder(), config).toString();
-    }
-
     void renameMap(MVMap<?, ?> map, String newName) {
         checkOpen();
         if (map == meta) {

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

@@ -18,7 +18,6 @@ import org.h2.index.Cursor;
 import org.h2.index.IndexType;
 import org.h2.message.DbException;
 import org.h2.mvstore.MVMap;
-import org.h2.mvstore.type.ObjectDataType;
 import org.h2.result.Row;
 import org.h2.result.SearchRow;
 import org.h2.result.SortOrder;
@@ -47,8 +46,8 @@ public class MVPrimaryIndex extends BaseIndex {
         }
         ValueArrayDataType t = new ValueArrayDataType(
                 db.getCompareMode(), db, sortTypes);
-        map = new MVMap<Long, Value[]>(new ObjectDataType(), t);
-        map = table.getStore().openMap(getName() + "_" + getId(), map);
+        map = table.getStore().openMap(getName() + "_" + getId(),
+                new MVMap.Builder<Long, Value[]>().valueType(t));
         Long k = map.lastKey();
         lastKey = k == null ? 0 : k;
     }

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

@@ -17,7 +17,6 @@ import org.h2.index.Cursor;
 import org.h2.index.IndexType;
 import org.h2.message.DbException;
 import org.h2.mvstore.MVMap;
-import org.h2.mvstore.type.ObjectDataType;
 import org.h2.result.Row;
 import org.h2.result.SearchRow;
 import org.h2.result.SortOrder;
@@ -52,10 +51,12 @@ public class MVSecondaryIndex extends BaseIndex {
             sortTypes[i] = columns[i].sortType;
         }
         sortTypes[keyColumns - 1] = SortOrder.ASCENDING;
+        String name = getName() + "_" + getId();
         ValueArrayDataType t = new ValueArrayDataType(
                 db.getCompareMode(), db, sortTypes);
-        map = new MVMap<Value[], Long>(t, new ObjectDataType());
-        map = table.getStore().openMap(getName() + "_" + getId(), map);
+        map = table.getStore().openMap(name,
+                new MVMap.Builder<Value[], Long>().keyType(t));
+
     }
 
     private static void checkIndexColumnTypes(IndexColumn[] columns) {

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

@@ -37,9 +37,4 @@ public class ValueDataTypeFactory implements DataTypeFactory {
         return parent.buildDataType(s);
     }
 
-    @Override
-    public String getDataType(Class<?> objectClass) {
-        return parent.getDataType(objectClass);
-    }
-
 }

h2/src/main/org/h2/mvstore/rtree/MVRTreeMap.java

@@ -13,6 +13,8 @@ import org.h2.mvstore.CursorPos;
 import org.h2.mvstore.MVMap;
 import org.h2.mvstore.Page;
 import org.h2.mvstore.type.DataType;
+import org.h2.mvstore.type.ObjectDataType;
+import org.h2.mvstore.type.StringDataType;
 import org.h2.util.New;
 
 /**
@@ -541,4 +543,53 @@ public class MVRTreeMap<V> extends MVMap<SpatialKey, V> {
         return "rtree";
     }
 
+    /**
+     * A builder for this class.
+     *
+     * @param <V> the value type
+     */
+    public static class Builder<V> implements
+            MVMap.MapBuilder<MVRTreeMap<V>, SpatialKey, V> {
+
+        private int dimensions = 2;
+        private DataType valueType;
+
+        /**
+         * Create a new builder for maps with 2 dimensions.
+         */
+        public Builder() {
+            // default
+        }
+
+        /**
+         * Set the dimensions.
+         *
+         * @param dimensions the dimensions to use
+         * @return this
+         */
+        public Builder<V> dimensions(int dimensions) {
+            this.dimensions = dimensions;
+            return this;
+        }
+
+        /**
+         * Set the key data type.
+         *
+         * @param valueType the key type
+         * @return this
+         */
+        public Builder<V> valueType(StringDataType valueType) {
+            this.valueType = valueType;
+            return this;
+        }
+
+        public MVRTreeMap<V> create() {
+            if (valueType == null) {
+                valueType = new ObjectDataType();
+            }
+            return new MVRTreeMap<V>(dimensions, valueType);
+        }
+
+    }
+
 }

h2/src/main/org/h2/mvstore/type/DataTypeFactory.java

@@ -26,15 +26,4 @@ public interface DataTypeFactory {
      */
     DataType buildDataType(String dataType);
 
-    /**
-     * Get the data type identifier for the given class.
-     * <p>
-     * To avoid conflict with the default factory, the returned string should
-     * start with the package name of the type factory.
-     *
-     * @param objectClass the class
-     * @return the data type identifier, or null if not supported
-     */
-    String getDataType(Class<?> objectClass);
-
 }

h2/src/main/org/h2/mvstore/type/ObjectDataTypeFactory.java

@@ -27,12 +27,4 @@ public class ObjectDataTypeFactory implements DataTypeFactory {
         return null;
     }
 
-    @Override
-    public String getDataType(Class<?> objectClass) {
-        if (objectClass == SpatialDataType.class) {
-            return "s";
-        }
-        return "o";
-    }
-
 }

h2/src/test/org/h2/test/TestBase.java

@@ -267,7 +267,7 @@ public abstract class TestBase {
             url = name;
         }
         int test;
-        // url = addOption(url, "DEFAULT_TABLE_ENGINE", MVTableEngine.class.getName());
+        url = addOption(url, "DEFAULT_TABLE_ENGINE", MVTableEngine.class.getName());
         if (!config.memory) {
             if (config.smallLog && admin) {
                 url = addOption(url, "MAX_LOG_SIZE", "1");

h2/src/test/org/h2/test/store/SampleTypeFactory.java

@@ -27,9 +27,4 @@ public class SampleTypeFactory implements DataTypeFactory {
         return parent.buildDataType(s);
     }
 
-    @Override
-    public String getDataType(Class<?> objectClass) {
-        return parent.getDataType(objectClass);
-    }
-
 }

h2/src/test/org/h2/test/store/SequenceMap.java

@@ -71,4 +71,23 @@ public class SequenceMap extends MVMap<Long, Long> {
         };
     }
 
+    /**
+     * A builder for this class.
+     */
+    public static class Builder implements MapBuilder<SequenceMap, Long, Long> {
+
+        /**
+         * Create a new builder.
+         */
+        public Builder() {
+            // ignore
+        }
+
+        @Override
+        public SequenceMap create() {
+            return new SequenceMap();
+        }
+
+    }
+
 }

h2/src/test/org/h2/test/store/TestConcurrent.java

@@ -50,8 +50,8 @@ public class TestConcurrent extends TestMVStore {
      */
     private void testConcurrentMap() throws InterruptedException {
         final MVStore s = openStore(null);
-        final MVMap<Integer, Integer> cm = MVMapConcurrent.create();
-        final MVMap<Integer, Integer> m = s.openMap("data", cm);
+        final MVMap<Integer, Integer> m = s.openMap("data",
+                new MVMapConcurrent.Builder<Integer, Integer>());
         final int size = 20;
         final Random rand = new Random(1);
         Task task = new Task() {
@@ -210,7 +210,7 @@ public class TestConcurrent extends TestMVStore {
      */
     private void testConcurrentWrite() throws InterruptedException {
         final MVStore s = openStore(null);
-        final MVMap<Integer, Integer> m = s.openMap("data", Integer.class, Integer.class);
+        final MVMap<Integer, Integer> m = s.openMap("data");
         final int size = 20;
         final Random rand = new Random(1);
         Task task = new Task() {
@@ -265,7 +265,7 @@ public class TestConcurrent extends TestMVStore {
 
     private void testConcurrentRead() throws InterruptedException {
         final MVStore s = openStore(null);
-        final MVMap<Integer, Integer> m = s.openMap("data", Integer.class, Integer.class);
+        final MVMap<Integer, Integer> m = s.openMap("data");
         final int size = 3;
         int x = (int) s.getCurrentVersion();
         for (int i = 0; i < size; i++) {

h2/src/test/org/h2/test/store/TestMVRTree.java

@@ -23,7 +23,6 @@ import javax.imageio.stream.FileImageOutputStream;
 import org.h2.mvstore.MVStore;
 import org.h2.mvstore.rtree.MVRTreeMap;
 import org.h2.mvstore.rtree.SpatialKey;
-import org.h2.mvstore.type.ObjectDataType;
 import org.h2.mvstore.type.StringDataType;
 import org.h2.store.fs.FileUtils;
 import org.h2.test.TestBase;
@@ -54,12 +53,9 @@ public class TestMVRTree extends TestMVStore {
         // create an in-memory store
         MVStore s = MVStore.open(null);
 
-        // create an R-tree map
-        // the key has 2 dimensions, the value is a string
-        MVRTreeMap<String> r = MVRTreeMap.create(2, new ObjectDataType());
-
-        // open the map
-        r = s.openMap("data", r);
+        // open an R-tree map
+        MVRTreeMap<String> r = s.openMap("data",
+                new MVRTreeMap.Builder<String>());
 
         // add two key-value pairs
         // the first value is the key id (to make the key unique)
@@ -84,8 +80,9 @@ public class TestMVRTree extends TestMVStore {
         MVStore s;
         s = openStore(fileName);
         // s.setMaxPageSize(50);
-        MVRTreeMap<String> r = MVRTreeMap.create(2, StringDataType.INSTANCE);
-        r = s.openMap("data", r);
+        MVRTreeMap<String> r = s.openMap("data",
+                new MVRTreeMap.Builder<String>().dimensions(2).
+                valueType(StringDataType.INSTANCE));
         // r.setQuadraticSplit(true);
         Random rand = new Random(1);
         int len = 1000;
@@ -109,8 +106,9 @@ public class TestMVRTree extends TestMVStore {
         s.store();
         s.close();
         s = openStore(fileName);
-        r = MVRTreeMap.create(2, StringDataType.INSTANCE);
-        r = s.openMap("data", r);
+        r = s.openMap("data",
+                new MVRTreeMap.Builder<String>().dimensions(2).
+                valueType(StringDataType.INSTANCE));
         // t = System.currentTimeMillis();
         rand = new Random(1);
         for (int i = 0; i < len; i++) {
@@ -148,8 +146,10 @@ public class TestMVRTree extends TestMVStore {
         FileUtils.delete(fileName);
         MVStore s;
         s = openStore(fileName);
-        MVRTreeMap<String> r = MVRTreeMap.create(2, StringDataType.INSTANCE);
-        r = s.openMap("data", r);
+        MVRTreeMap<String> r = s.openMap("data",
+                new MVRTreeMap.Builder<String>().dimensions(2).
+                valueType(StringDataType.INSTANCE));
+
         add(r, "Bern", key(0, 46.57, 7.27, 124381));
         add(r, "Basel", key(1, 47.34, 7.36, 170903));
         add(r, "Zurich", key(2, 47.22, 8.33, 376008));
@@ -273,9 +273,11 @@ public class TestMVRTree extends TestMVStore {
         String fileName = getBaseDir() + "/testRandom.h3";
         FileUtils.delete(fileName);
         MVStore s = openStore(fileName);
-        MVRTreeMap<String> m = MVRTreeMap.create(2, StringDataType.INSTANCE);
+
+        MVRTreeMap<String> m = s.openMap("data",
+                new MVRTreeMap.Builder<String>());
+
         m.setQuadraticSplit(quadraticSplit);
-        m = s.openMap("data", m);
         HashMap<SpatialKey, String> map = new HashMap<SpatialKey, String>();
         Random rand = new Random(1);
         int operationCount = 1000;

h2/src/test/org/h2/test/store/TestMVTableEngine.java

@@ -28,7 +28,7 @@ public class TestMVTableEngine extends TestBase {
     }
 
     public void test() throws Exception {
-        // testCase();
+        testCase();
         testSimple();
     }