[534254] [DB] Create all mapped tables lazily

https://bugs.eclipse.org/bugs/show_bug.cgi?id=534254

6 files changed, 116 insertions, 43 deletions

diff --git a/plugins/org.eclipse.net4j.db/META-INF/MANIFEST.MF b/plugins/org.eclipse.net4j.db/META-INF/MANIFEST.MF
index 63f0e1c58f..a56d80f2d5 100644
--- a/plugins/org.eclipse.net4j.db/META-INF/MANIFEST.MF
+++ b/plugins/org.eclipse.net4j.db/META-INF/MANIFEST.MF
@@ -2,7 +2,7 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: %pluginName
 Bundle-SymbolicName: org.eclipse.net4j.db;singleton:=true
-Bundle-Version: 4.6.100.qualifier
+Bundle-Version: 4.7.0.qualifier
 Bundle-Activator: org.eclipse.net4j.internal.db.bundle.OM$Activator
 Bundle-Vendor: %providerName
 Bundle-ClassPath: .
@@ -11,17 +11,17 @@ Bundle-RequiredExecutionEnvironment: J2SE-1.5
 Require-Bundle: org.eclipse.core.runtime;bundle-version="[3.5.0,4.0.0)",
  org.eclipse.net4j.util;bundle-version="[3.0.0,4.0.0)";visibility:=reexport,
  org.eclipse.net4j.db.jdbc;bundle-version="[4.0.0,5.0.0)"
-Export-Package: org.eclipse.net4j.db;version="4.6.100",
- org.eclipse.net4j.db.ddl;version="4.6.100",
- org.eclipse.net4j.db.ddl.delta;version="4.6.100",
- org.eclipse.net4j.db.dml;version="4.6.100",
- org.eclipse.net4j.internal.db;version="4.6.100";x-internal:=true,
- org.eclipse.net4j.internal.db.bundle;version="4.6.100";x-internal:=true,
- org.eclipse.net4j.internal.db.ddl;version="4.6.100";x-friends:="org.eclipse.emf.cdo.server.db",
- org.eclipse.net4j.internal.db.ddl.delta;version="4.6.100";x-internal:=true,
- org.eclipse.net4j.internal.db.dml;version="4.6.100";x-internal:=true,
- org.eclipse.net4j.spi.db;version="4.6.100",
- org.eclipse.net4j.spi.db.ddl;version="4.6.100"
+Export-Package: org.eclipse.net4j.db;version="4.7.0",
+ org.eclipse.net4j.db.ddl;version="4.7.0",
+ org.eclipse.net4j.db.ddl.delta;version="4.7.0",
+ org.eclipse.net4j.db.dml;version="4.7.0",
+ org.eclipse.net4j.internal.db;version="4.7.0";x-internal:=true,
+ org.eclipse.net4j.internal.db.bundle;version="4.7.0";x-internal:=true,
+ org.eclipse.net4j.internal.db.ddl;version="4.7.0";x-friends:="org.eclipse.emf.cdo.server.db",
+ org.eclipse.net4j.internal.db.ddl.delta;version="4.7.0";x-internal:=true,
+ org.eclipse.net4j.internal.db.dml;version="4.7.0";x-internal:=true,
+ org.eclipse.net4j.spi.db;version="4.7.0",
+ org.eclipse.net4j.spi.db.ddl;version="4.7.0"
 Bundle-ActivationPolicy: lazy
 Eclipse-BuddyPolicy: registered
 Automatic-Module-Name: org.eclipse.net4j.db
diff --git a/plugins/org.eclipse.net4j.db/pom.xml b/plugins/org.eclipse.net4j.db/pom.xml
index fa80a1808a..df0ef3a7e1 100644
--- a/plugins/org.eclipse.net4j.db/pom.xml
+++ b/plugins/org.eclipse.net4j.db/pom.xml
@@ -25,7 +25,7 @@
 
   <groupId>org.eclipse.emf.cdo</groupId>
   <artifactId>org.eclipse.net4j.db</artifactId>
-  <version>4.6.100-SNAPSHOT</version>
+  <version>4.7.0-SNAPSHOT</version>
   <packaging>eclipse-plugin</packaging>
 
 </project>
diff --git a/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/db/IDBDatabase.java b/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/db/IDBDatabase.java
index 2eb04118e4..24b9a477c9 100644
--- a/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/db/IDBDatabase.java
+++ b/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/db/IDBDatabase.java
@@ -32,6 +32,15 @@ public interface IDBDatabase extends IContainer<IDBConnection>, IDBConnectionPro
 
   public IDBSchemaTransaction openSchemaTransaction();
 
+  /**
+   * @since 4.7
+   */
+  public IDBSchemaTransaction openSchemaTransaction(IDBConnection connection);
+
+  /**
+   * @deprecated As of 4.7 no longer supported in favor of support for multiple schema transactions.
+   */
+  @Deprecated
   public IDBSchemaTransaction getSchemaTransaction();
 
   public void updateSchema(RunnableWithSchema runnable);
diff --git a/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBConnection.java b/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBConnection.java
index 45998e809c..13e66b454d 100644
--- a/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBConnection.java
+++ b/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBConnection.java
@@ -84,8 +84,7 @@ public final class DBConnection extends DelegatingConnection implements IDBConne
 
   public IDBSchemaTransaction openSchemaTransaction()
   {
-    DBSchemaTransaction schemaTransaction = database.openSchemaTransaction();
-    schemaTransaction.setConnection(this);
+    DBSchemaTransaction schemaTransaction = database.openSchemaTransaction(this);
     return schemaTransaction;
   }
 
diff --git a/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBDatabase.java b/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBDatabase.java
index 5df41b046f..9247b31957 100644
--- a/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBDatabase.java
+++ b/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBDatabase.java
@@ -22,8 +22,11 @@ import org.eclipse.net4j.internal.db.ddl.delta.DBSchemaDelta;
 import org.eclipse.net4j.spi.db.DBAdapter;
 import org.eclipse.net4j.spi.db.ddl.InternalDBSchema;
 import org.eclipse.net4j.util.WrappedException;
+import org.eclipse.net4j.util.concurrent.TimeoutRuntimeException;
 import org.eclipse.net4j.util.container.SetContainer;
 import org.eclipse.net4j.util.event.Event;
+import org.eclipse.net4j.util.io.IOUtil;
+import org.eclipse.net4j.util.om.OMPlatform;
 import org.eclipse.net4j.util.security.IUserAware;
 
 import java.sql.Connection;
@@ -35,6 +38,11 @@ import java.util.LinkedList;
  */
 public final class DBDatabase extends SetContainer<IDBConnection> implements IDBDatabase
 {
+  private static final long TIMEOUT_SCHEMA_ACCESS = Long
+      .parseLong(OMPlatform.INSTANCE.getProperty("org.eclipse.net4j.internal.db.DBDatabase.TIMEOUT_SCHEMA_ACCESS", "15000"));
+
+  private static final boolean DEBUG_SCHEMA_ACCESS = OMPlatform.INSTANCE.isProperty("org.eclipse.net4j.internal.db.DBDatabase.DEBUG_SCHEMA_ACCESS");
+
   private DBAdapter adapter;
 
   private IDBConnectionProvider connectionProvider;
@@ -43,10 +51,10 @@ public final class DBDatabase extends SetContainer<IDBConnection> implements IDB
 
   private IDBSchema schema;
 
-  private DBSchemaTransaction schemaTransaction;
-
   private final LinkedList<SchemaAccess> schemaAccessQueue = new LinkedList<SchemaAccess>();
 
+  private int schemaWriters;
+
   public DBDatabase(final DBAdapter adapter, IDBConnectionProvider connectionProvider, final String schemaName, final boolean fixNullableIndexColumns)
   {
     super(IDBConnection.class);
@@ -87,13 +95,23 @@ public final class DBDatabase extends SetContainer<IDBConnection> implements IDB
 
   public DBSchemaTransaction openSchemaTransaction()
   {
+    return openSchemaTransaction(null);
+  }
+
+  public DBSchemaTransaction openSchemaTransaction(IDBConnection connection)
+  {
     DBSchemaTransaction schemaTransaction = new DBSchemaTransaction(this);
-    this.schemaTransaction = schemaTransaction;
+    schemaTransaction.setConnection((DBConnection)connection);
     return schemaTransaction;
   }
 
   public void closeSchemaTransaction(DBSchemaDelta delta)
   {
+    if (delta == null || delta.isEmpty())
+    {
+      return;
+    }
+
     try
     {
       beginSchemaAccess(true);
@@ -103,18 +121,18 @@ public final class DBDatabase extends SetContainer<IDBConnection> implements IDB
         ((DBConnection)transaction).invalidateStatementCache();
       }
 
-      fireEvent(new SchemaChangedEventImpl(delta));
+      fireEvent(new SchemaChangedEventImpl(this, delta));
     }
     finally
     {
-      schemaTransaction = null;
       endSchemaAccess();
     }
   }
 
+  @Deprecated
   public DBSchemaTransaction getSchemaTransaction()
   {
-    return schemaTransaction;
+    throw new UnsupportedOperationException();
   }
 
   public void updateSchema(RunnableWithSchema runnable)
@@ -191,6 +209,18 @@ public final class DBDatabase extends SetContainer<IDBConnection> implements IDB
 
   public void beginSchemaAccess(boolean write)
   {
+    if (DEBUG_SCHEMA_ACCESS)
+    {
+      try
+      {
+        throw new Exception("Begin " + (write ? "write" : "read") + " schema access: " + schema.getName());
+      }
+      catch (Exception ex)
+      {
+        ex.printStackTrace(IOUtil.OUT());
+      }
+    }
+
     SchemaAccess schemaAccess = null;
     synchronized (schemaAccessQueue)
     {
@@ -198,10 +228,11 @@ public final class DBDatabase extends SetContainer<IDBConnection> implements IDB
       {
         schemaAccess = new WriteSchemaAccess();
         schemaAccessQueue.addLast(schemaAccess);
+        ++schemaWriters;
       }
       else
       {
-        if (!schemaAccessQueue.isEmpty())
+        if (schemaWriters == 0 && !schemaAccessQueue.isEmpty())
         {
           schemaAccess = schemaAccessQueue.getFirst();
           if (schemaAccess instanceof ReadSchemaAccess)
@@ -223,29 +254,52 @@ public final class DBDatabase extends SetContainer<IDBConnection> implements IDB
       }
     }
 
-    for (;;)
+    long end = System.currentTimeMillis() + TIMEOUT_SCHEMA_ACCESS;
+
+    do
     {
       synchronized (schemaAccessQueue)
       {
         if (schemaAccessQueue.getFirst() == schemaAccess)
         {
+          if (write)
+          {
+            --schemaWriters;
+          }
+
           return;
         }
 
         try
         {
-          schemaAccessQueue.wait();
+          schemaAccessQueue.wait(1000L);
         }
         catch (InterruptedException ex)
         {
+          Thread.currentThread().interrupt();
           throw WrappedException.wrap(ex);
         }
       }
-    }
+    } while (System.currentTimeMillis() < end);
+
+    throw new TimeoutRuntimeException(
+        "Schema " + schema.getName() + " could not be locked for " + (write ? "write" : "read") + " access within " + TIMEOUT_SCHEMA_ACCESS + " milliseconds");
   }
 
   public void endSchemaAccess()
   {
+    if (DEBUG_SCHEMA_ACCESS)
+    {
+      try
+      {
+        throw new Exception("End schema access: " + schema.getName());
+      }
+      catch (Exception ex)
+      {
+        ex.printStackTrace(IOUtil.OUT());
+      }
+    }
+
     synchronized (schemaAccessQueue)
     {
       SchemaAccess schemaAccess = schemaAccessQueue.getFirst();
@@ -288,7 +342,7 @@ public final class DBDatabase extends SetContainer<IDBConnection> implements IDB
   /**
    * @author Eike Stepper
    */
-  private final class ReadSchemaAccess implements SchemaAccess
+  private static final class ReadSchemaAccess implements SchemaAccess
   {
     private int readers = 1;
 
@@ -312,7 +366,7 @@ public final class DBDatabase extends SetContainer<IDBConnection> implements IDB
   /**
    * @author Eike Stepper
    */
-  private final class WriteSchemaAccess implements SchemaAccess
+  private static final class WriteSchemaAccess implements SchemaAccess
   {
     @Override
     public String toString()
@@ -324,15 +378,15 @@ public final class DBDatabase extends SetContainer<IDBConnection> implements IDB
   /**
    * @author Eike Stepper
    */
-  private final class SchemaChangedEventImpl extends Event implements SchemaChangedEvent
+  private static final class SchemaChangedEventImpl extends Event implements SchemaChangedEvent
   {
     private static final long serialVersionUID = 1L;
 
     private final IDBSchemaDelta schemaDelta;
 
-    public SchemaChangedEventImpl(IDBSchemaDelta schemaDelta)
+    public SchemaChangedEventImpl(DBDatabase database, IDBSchemaDelta schemaDelta)
     {
-      super(DBDatabase.this);
+      super(database);
       this.schemaDelta = schemaDelta;
     }
 
diff --git a/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBSchemaTransaction.java b/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBSchemaTransaction.java
index 970a166624..525766124e 100644
--- a/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBSchemaTransaction.java
+++ b/plugins/org.eclipse.net4j.db/src/org/eclipse/net4j/internal/db/DBSchemaTransaction.java
@@ -37,6 +37,8 @@ public final class DBSchemaTransaction implements IDBSchemaTransaction, Runnable
 
   private IDBSchema oldSchema;
 
+  private IDBSchema oldSchemaCopy;
+
   private IDBSchema workingCopy;
 
   public DBSchemaTransaction(DBDatabase database)
@@ -44,6 +46,8 @@ public final class DBSchemaTransaction implements IDBSchemaTransaction, Runnable
     this.database = database;
 
     oldSchema = database.getSchema();
+    oldSchemaCopy = DBUtil.copySchema(oldSchema);
+
     IDBSchema copy = DBUtil.copySchema(oldSchema);
     workingCopy = DelegatingDBSchemaElement.wrap(copy);
   }
@@ -89,7 +93,7 @@ public final class DBSchemaTransaction implements IDBSchemaTransaction, Runnable
 
   public DBSchemaDelta getSchemaDelta()
   {
-    return (DBSchemaDelta)workingCopy.compare(oldSchema);
+    return (DBSchemaDelta)workingCopy.compare(oldSchemaCopy);
   }
 
   public DBSchemaDelta commit()
@@ -99,6 +103,9 @@ public final class DBSchemaTransaction implements IDBSchemaTransaction, Runnable
       return DBUtil.execute(database, this);
     }
 
+    // Remember connection locally because the instance field will be reset in run/doClose.
+    DBConnection connection = this.connection;
+
     try
     {
       DBSchemaDelta result = run(connection);
@@ -116,19 +123,22 @@ public final class DBSchemaTransaction implements IDBSchemaTransaction, Runnable
   {
     DBSchemaDelta delta = getSchemaDelta();
 
-    try
-    {
-      ((InternalDBSchema)oldSchema).unlock();
-
-      DBAdapter adapter = database.getAdapter();
-      adapter.updateSchema(connection, oldSchema, delta);
-
-      ((DelegatingDBSchema)workingCopy).setDelegate(oldSchema);
-    }
-    finally
+    synchronized (oldSchema)
     {
-      ((InternalDBSchema)oldSchema).lock();
-      doClose(delta);
+      try
+      {
+        ((InternalDBSchema)oldSchema).unlock();
+
+        DBAdapter adapter = database.getAdapter();
+        adapter.updateSchema(connection, oldSchema, delta);
+
+        ((DelegatingDBSchema)workingCopy).setDelegate(oldSchema);
+      }
+      finally
+      {
+        ((InternalDBSchema)oldSchema).lock();
+        doClose(delta);
+      }
     }
 
     return delta;
@@ -146,6 +156,7 @@ public final class DBSchemaTransaction implements IDBSchemaTransaction, Runnable
       database.closeSchemaTransaction(delta);
       connection = null;
       oldSchema = null;
+      oldSchemaCopy = null;
       workingCopy = null;
     }
   }