New experimental page store.

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

@@ -9,6 +9,7 @@ package org.h2.command.dml;
 import java.sql.SQLException;
 
 import org.h2.command.Prepared;
+import org.h2.constant.SysProperties;
 import org.h2.engine.Database;
 import org.h2.engine.Session;
 import org.h2.log.LogSystem;
@@ -123,8 +124,8 @@ public class TransactionCommand extends Prepared {
             break;
         case CHECKPOINT:
             session.getUser().checkAdmin();
-            PageStore store = session.getDatabase().getPageStore();
-            if (store != null) {
+            if (SysProperties.PAGE_STORE) {
+                PageStore store = session.getDatabase().getPageStore();
                 store.checkpoint();
             }
             session.getDatabase().getLog().checkpoint();

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

@@ -2091,7 +2091,7 @@ public class Database implements DataHandler {
     }
 
     public PageStore getPageStore() throws SQLException {
-        if (pageStore == null) {
+        if (pageStore == null && SysProperties.PAGE_STORE) {
             pageStore = new PageStore(this, databaseName + Constants.SUFFIX_PAGE_FILE, accessModeData,
                     SysProperties.CACHE_SIZE_DEFAULT);
             pageStore.open();

h2/src/main/org/h2/log/LogSystem.java

@@ -42,7 +42,7 @@ public class LogSystem {
     private LogFile currentLog;
     private String fileNamePrefix;
     private HashMap storages = new HashMap();
-    private HashMap sessions = new HashMap();
+    private HashMap sessionStates = new HashMap();
     private DataPage rowBuff;
     private ObjectArray undo;
     // TODO log file / deleteOldLogFilesAutomatically:
@@ -252,7 +252,7 @@ public class LogSystem {
                 database.getIndexFile().flushRedoLog();
             }
             int end = currentLog.getPos();
-            Object[] states = sessions.values().toArray();
+            Object[] states = sessionStates.values().toArray();
             inDoubtTransactions = new ObjectArray();
             for (int i = 0; i < states.length; i++) {
                 SessionState state = (SessionState) states[i];
@@ -260,10 +260,10 @@ public class LogSystem {
                     inDoubtTransactions.add(state.inDoubtTransaction);
                 }
             }
-            for (int i = undo.size() - 1; i >= 0 && sessions.size() > 0; i--) {
+            for (int i = undo.size() - 1; i >= 0 && sessionStates.size() > 0; i--) {
                 database.setProgress(DatabaseEventListener.STATE_RECOVER, null, undo.size() - 1 - i, undo.size());
                 LogRecord record = (LogRecord) undo.get(i);
-                if (sessions.get(ObjectUtils.getInteger(record.sessionId)) != null) {
+                if (sessionStates.get(ObjectUtils.getInteger(record.sessionId)) != null) {
                     // undo only if the session is not yet committed
                     record.log.undo(record.logRecordId);
                     database.getDataFile().flushRedoLog();
@@ -359,7 +359,7 @@ public class LogSystem {
      */
     boolean isSessionCommitted(int sessionId, int logId, int pos) {
         Integer key = ObjectUtils.getInteger(sessionId);
-        SessionState state = (SessionState) sessions.get(key);
+        SessionState state = (SessionState) sessionStates.get(key);
         if (state == null) {
             return true;
         }
@@ -389,10 +389,10 @@ public class LogSystem {
      */
     SessionState getOrAddSessionState(int sessionId) {
         Integer key = ObjectUtils.getInteger(sessionId);
-        SessionState state = (SessionState) sessions.get(key);
+        SessionState state = (SessionState) sessionStates.get(key);
         if (state == null) {
             state = new SessionState();
-            sessions.put(key, state);
+            sessionStates.put(key, state);
             state.sessionId = sessionId;
         }
         return state;
@@ -433,7 +433,7 @@ public class LogSystem {
      * @param sessionId the session id
      */
     void removeSession(int sessionId) {
-        sessions.remove(ObjectUtils.getInteger(sessionId));
+        sessionStates.remove(ObjectUtils.getInteger(sessionId));
     }
 
     /**

h2/src/main/org/h2/log/SessionState.java

@@ -15,22 +15,22 @@ public class SessionState {
     /**
      * The session id
      */
-    int sessionId;
+    public int sessionId;
 
     /**
      * The last log file id where a commit for this session is found.
      */
-    int lastCommitLog;
+    public int lastCommitLog;
 
     /**
      * The position where a commit for this session is found.
      */
-    int lastCommitPos;
+    public int lastCommitPos;
 
     /**
      * The in-doubt transaction if there is one.
      */
-    InDoubtTransaction inDoubtTransaction;
+    public InDoubtTransaction inDoubtTransaction;
 
     /**
      * Check if this session state is already committed at this point.
@@ -39,7 +39,7 @@ public class SessionState {
      * @param pos the position in the log file
      * @return true if it is committed
      */
-    boolean isCommitted(int logId, int pos) {
+    public boolean isCommitted(int logId, int pos) {
         if (logId != lastCommitLog) {
             return lastCommitLog > logId;
         }