org.eclipse.persistence.internal.databaseaccess.DynamicSQLBatchWritingMechanism Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 1998, 2013 Oracle and/or its affiliates. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.internal.databaseaccess;
import java.io.StringWriter;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Iterator;
import org.eclipse.persistence.descriptors.DescriptorQueryManager;
import org.eclipse.persistence.exceptions.DatabaseException;
import org.eclipse.persistence.exceptions.OptimisticLockException;
import org.eclipse.persistence.internal.sessions.AbstractSession;
import org.eclipse.persistence.logging.SessionLog;
import org.eclipse.persistence.queries.ModifyQuery;
import org.eclipse.persistence.sessions.SessionProfiler;
/**
* INTERNAL:
* DynamicSQLBatchWritingMechanism is a private class, used by the DatabaseAccessor.
* It provides the required behavior for batching statements, for write, with parameter binding turned off.
*/
public class DynamicSQLBatchWritingMechanism extends BatchWritingMechanism {
/**
* This variable is used to store the SQLStrings that are being batched
*/
protected ArrayList sqlStrings;
/**
* Stores the statement indexes for statements that are using optimistic locking. This allows us to check individual
* statement results on supported platforms
*/
/**
* This attribute is used to store the maximum length of all strings batched together
*/
protected long batchSize;
/**
* Records if this batch uses optimistic locking.
*/
protected boolean usesOptimisticLocking;
public DynamicSQLBatchWritingMechanism(DatabaseAccessor databaseAccessor) {
this.databaseAccessor = databaseAccessor;
this.sqlStrings = new ArrayList(10);
this.batchSize = 0;
this.maxBatchSize = this.databaseAccessor.getLogin().getPlatform().getMaxBatchWritingSize();
if (this.maxBatchSize == 0) {
// the max size was not set on the platform - use default
this.maxBatchSize = DatabasePlatform.DEFAULT_MAX_BATCH_WRITING_SIZE;
}
}
/**
* INTERNAL:
* This method is called by the DatabaseAccessor to add this statement to the list of statements
* being batched. This call may result in the Mechanism executing the batched statements and
* possibly, switching out the mechanisms
*/
public void appendCall(AbstractSession session, DatabaseCall dbCall) {
// Store the largest queryTimeout on a single call for later use by the single statement in prepareJDK12BatchStatement
if(dbCall != null) {
cacheQueryTimeout(session, dbCall);
}
if (!dbCall.hasParameters()) {
if ((batchSize + dbCall.getSQLString().length()) > this.maxBatchSize) {
executeBatchedStatements(session);
}
if (this.usesOptimisticLocking != dbCall.hasOptimisticLock){
executeBatchedStatements(session);
}
this.sqlStrings.add(dbCall.getSQLString());
this.batchSize += dbCall.getSQLString().length();
this.usesOptimisticLocking = dbCall.hasOptimisticLock;
++this.statementCount;
// feature for bug 4104613, allows users to force statements to flush on execution
if (((ModifyQuery) dbCall.getQuery()).forceBatchStatementExecution())
{
executeBatchedStatements(session);
}
} else {
executeBatchedStatements(session);
this.switchMechanisms(session, dbCall);
}
}
/**
* INTERNAL:
* This method is used to clear the batched statements without the need to execute the statements first
* This is used in the case of rollback.
*/
public void clear() {
this.sqlStrings.clear();
statementCount = executionCount = 0;
this.usesOptimisticLocking = false;
this.batchSize = 0;
clearCacheQueryTimeout();
}
/**
* INTERNAL:
* This method is used by the DatabaseAccessor to execute and clear the batched statements in the
* case that a non batchable statement is being executed
*/
public void executeBatchedStatements(AbstractSession session) {
if (this.sqlStrings.isEmpty()) {
return;
}
try {
this.databaseAccessor.writeStatementsCount++;
this.databaseAccessor.incrementCallCount(session);// Decrement occurs in close.
if (session.shouldLog(SessionLog.FINE, SessionLog.SQL)) {
session.log(SessionLog.FINER, SessionLog.SQL, "begin_batch_statements", null, this.databaseAccessor);
for (Iterator sqlStringsIterator = this.sqlStrings.iterator();
sqlStringsIterator.hasNext();) {
session.log(SessionLog.FINE, SessionLog.SQL, (String)sqlStringsIterator.next(), null, this.databaseAccessor, false);
}
session.log(SessionLog.FINER, SessionLog.SQL, "end_batch_statements", null, this.databaseAccessor);
}
if (!session.getPlatform().usesJDBCBatchWriting()) {
PreparedStatement statement = prepareBatchStatement(session);
this.databaseAccessor.executeBatchedStatement(statement, session);
} else {
//lets add optimistic locking support.
Statement statement = prepareJDK12BatchStatement(session);
executionCount += this.databaseAccessor.executeJDK12BatchStatement(statement, null, session, false);
if (this.usesOptimisticLocking && (executionCount!=statementCount)){
throw OptimisticLockException.batchStatementExecutionFailure();
}
}
} finally {
// Reset the batched sql string
this.clear();
}
}
/**
* INTERNAL:
* This method is used to switch from this mechanism to the alternate automatically
*/
protected void switchMechanisms(AbstractSession session, DatabaseCall dbCall) {
this.databaseAccessor.setActiveBatchWritingMechanismToParameterizedSQL();
this.databaseAccessor.getActiveBatchWritingMechanism().appendCall(session, dbCall);
}
/**
* INTERNAL:
* This method is used to build the batch statement by concatenating the strings
* together.
*/
protected PreparedStatement prepareBatchStatement(AbstractSession session) throws DatabaseException {
PreparedStatement statement = null;
boolean isDelimiterStringNeeded = false;
StringWriter writer = new StringWriter();
DatabasePlatform platform = session.getPlatform();
writer.write(platform.getBatchBeginString());
for (Iterator sqlStringsIteration = this.sqlStrings.iterator();
sqlStringsIteration.hasNext();) {
if (isDelimiterStringNeeded) {
writer.write(platform.getBatchDelimiterString());
}
writer.write((String)sqlStringsIteration.next());
isDelimiterStringNeeded = true;
}
writer.write(platform.getBatchDelimiterString());
writer.write(platform.getBatchEndString());
try {
session.startOperationProfile(SessionProfiler.SqlPrepare, null, SessionProfiler.ALL);
try {
statement = this.databaseAccessor.getConnection().prepareStatement(writer.toString());
} finally {
session.endOperationProfile(SessionProfiler.SqlPrepare, null, SessionProfiler.ALL);
}
} catch (SQLException exception) {
//If this is a connection from an external pool then closeStatement will close the connection.
//we must test the connection before that happens.
DatabaseException exceptionToThrow = this.databaseAccessor.processExceptionForCommError(session, exception, null);
try {// Ensure that the statement is closed, but still ensure that the real exception is thrown.
this.databaseAccessor.closeStatement(statement, session, null);
} catch (SQLException closeException) {
}
if (exceptionToThrow == null){
throw DatabaseException.sqlException(exception, this.databaseAccessor, session, false);
}
throw exceptionToThrow;
} catch (RuntimeException exception) {
try {// Ensure that the statement is closed, but still ensure that the real exception is thrown.
this.databaseAccessor.closeStatement(statement, session, null);
} catch (SQLException closeException) {
}
throw exception;
}
return statement;
}
/**
* INTERNAL:
* This method is used to build the batch statement for the JDBC2.0 specification
*/
protected Statement prepareJDK12BatchStatement(AbstractSession session) throws DatabaseException {
Statement statement = null;
try {
session.startOperationProfile(SessionProfiler.SqlPrepare, null, SessionProfiler.ALL);
try {
statement = this.databaseAccessor.getConnection().createStatement();
for (Iterator sqlStringsIterator = this.sqlStrings.iterator();
sqlStringsIterator.hasNext();) {
statement.addBatch((String)sqlStringsIterator.next());
}
// Set the query timeout that was cached during the multiple calls to appendCall
if(queryTimeoutCache > DescriptorQueryManager.NoTimeout) {
statement.setQueryTimeout(queryTimeoutCache);
}
} finally {
session.endOperationProfile(SessionProfiler.SqlPrepare, null, SessionProfiler.ALL);
}
} catch (SQLException exception) {
//If this is a connection from an external pool then closeStatement will close the connection.
//we must test the connection before that happens.
RuntimeException exceptionToThrow = this.databaseAccessor.processExceptionForCommError(session, exception, null);
try {// Ensure that the statement is closed, but still ensure that the real exception is thrown.
this.databaseAccessor.closeStatement(statement, session, null);
} catch (SQLException closeException) {
}
if (exceptionToThrow == null){
throw DatabaseException.sqlException(exception, this.databaseAccessor, session, false);
}
throw exceptionToThrow;
} catch (RuntimeException exception) {
try {// Ensure that the statement is closed, but still ensure that the real exception is thrown.
this.databaseAccessor.closeStatement(statement, session, null);
} catch (SQLException closeException) {
}
throw exception;
}
return statement;
}
}