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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.dbcp2;
import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.NoSuchElementException;
import org.apache.commons.pool2.KeyedObjectPool;
import org.apache.commons.pool2.KeyedPooledObjectFactory;
import org.apache.commons.pool2.PooledObject;
import org.apache.commons.pool2.impl.DefaultPooledObject;
/**
* A {@link DelegatingConnection} that pools {@link PreparedStatement}s.
*
* The {@link #prepareStatement} and {@link #prepareCall} methods, rather than
* creating a new PreparedStatement each time, may actually pull the statement
* from a pool of unused statements.
* The {@link PreparedStatement#close} method of the returned statement doesn't
* actually close the statement, but rather returns it to the pool.
* (See {@link PoolablePreparedStatement}, {@link PoolableCallableStatement}.)
*
*
* @see PoolablePreparedStatement
* @author Rodney Waldhoff
* @author Dirk Verbeeck
* @version $Revision: 1572244 $ $Date: 2014-02-26 20:38:08 +0000 (Wed, 26 Feb 2014) $
* @since 2.0
*/
public class PoolingConnection extends DelegatingConnection
implements KeyedPooledObjectFactory {
/** Pool of {@link PreparedStatement}s. and {@link CallableStatement}s */
private KeyedObjectPool _pstmtPool = null;
/**
* Constructor.
* @param c the underlying {@link Connection}.
*/
public PoolingConnection(Connection c) {
super(c);
}
public void setStatementPool(
KeyedObjectPool pool) {
_pstmtPool = pool;
}
/**
* Close and free all {@link PreparedStatement}s or
* {@link CallableStatement}s from the pool, and close the underlying
* connection.
*/
@Override
public synchronized void close() throws SQLException {
try {
if (null != _pstmtPool) {
KeyedObjectPool oldpool = _pstmtPool;
_pstmtPool = null;
try {
oldpool.close();
} catch(RuntimeException e) {
throw e;
} catch(Exception e) {
throw new SQLException("Cannot close connection", e);
}
}
} finally {
try {
getDelegateInternal().close();
} finally {
setClosedInternal(true);
}
}
}
/**
* Create or obtain a {@link PreparedStatement} from the pool.
* @param sql the sql string used to define the PreparedStatement
* @return a {@link PoolablePreparedStatement}
*/
@Override
public PreparedStatement prepareStatement(String sql) throws SQLException {
if (null == _pstmtPool) {
throw new SQLException(
"Statement pool is null - closed or invalid PoolingConnection.");
}
try {
return _pstmtPool.borrowObject(createKey(sql));
} catch(NoSuchElementException e) {
throw new SQLException("MaxOpenPreparedStatements limit reached", e);
} catch(RuntimeException e) {
throw e;
} catch(Exception e) {
throw new SQLException("Borrow prepareStatement from pool failed", e);
}
}
@Override
public PreparedStatement prepareStatement(String sql, int autoGeneratedKeys) throws SQLException {
if (null == _pstmtPool) {
throw new SQLException(
"Statement pool is null - closed or invalid PoolingConnection.");
}
try {
return _pstmtPool.borrowObject(createKey(sql, autoGeneratedKeys));
}
catch (NoSuchElementException e) {
throw new SQLException("MaxOpenPreparedStatements limit reached", e);
}
catch (RuntimeException e) {
throw e;
}
catch (Exception e) {
throw new SQLException("Borrow prepareStatement from pool failed", e);
}
}
/**
* Create or obtain a {@link PreparedStatement} from the pool.
* @param sql the sql string used to define the PreparedStatement
* @param resultSetType result set type
* @param resultSetConcurrency result set concurrency
* @return a {@link PoolablePreparedStatement}
*/
@Override
public PreparedStatement prepareStatement(String sql, int resultSetType, int resultSetConcurrency) throws SQLException {
if (null == _pstmtPool) {
throw new SQLException(
"Statement pool is null - closed or invalid PoolingConnection.");
}
try {
return _pstmtPool.borrowObject(createKey(sql,resultSetType,resultSetConcurrency));
} catch(NoSuchElementException e) {
throw new SQLException("MaxOpenPreparedStatements limit reached", e);
} catch(RuntimeException e) {
throw e;
} catch(Exception e) {
throw new SQLException("Borrow prepareStatement from pool failed", e);
}
}
/**
* Create or obtain a {@link CallableStatement} from the pool.
* @param sql the sql string used to define the CallableStatement
* @return a {@link PoolableCallableStatement}
* @throws SQLException
*/
@Override
public CallableStatement prepareCall(String sql) throws SQLException {
try {
return (CallableStatement) _pstmtPool.borrowObject(createKey(sql, StatementType.CALLABLE_STATEMENT));
} catch (NoSuchElementException e) {
throw new SQLException("MaxOpenCallableStatements limit reached", e);
} catch (RuntimeException e) {
throw e;
} catch (Exception e) {
throw new SQLException("Borrow callableStatement from pool failed", e);
}
}
/**
* Create or obtain a {@link CallableStatement} from the pool.
* @param sql the sql string used to define the CallableStatement
* @param resultSetType result set type
* @param resultSetConcurrency result set concurrency
* @return a {@link PoolableCallableStatement}
* @throws SQLException
*/
@Override
public CallableStatement prepareCall(String sql, int resultSetType, int resultSetConcurrency) throws SQLException {
try {
return (CallableStatement) _pstmtPool.borrowObject(createKey(sql, resultSetType,
resultSetConcurrency, StatementType.CALLABLE_STATEMENT));
} catch (NoSuchElementException e) {
throw new SQLException("MaxOpenCallableStatements limit reached", e);
} catch (RuntimeException e) {
throw e;
} catch (Exception e) {
throw new SQLException("Borrow callableStatement from pool failed", e);
}
}
// TODO: possible enhancement, cache these preparedStatements as well
// public PreparedStatement prepareStatement(String sql, int resultSetType,
// int resultSetConcurrency,
// int resultSetHoldability)
// throws SQLException {
// return super.prepareStatement(
// sql, resultSetType, resultSetConcurrency, resultSetHoldability);
// }
//
// public PreparedStatement prepareStatement(String sql, int columnIndexes[])
// throws SQLException {
// return super.prepareStatement(sql, columnIndexes);
// }
//
// public PreparedStatement prepareStatement(String sql, String columnNames[])
// throws SQLException {
// return super.prepareStatement(sql, columnNames);
// }
protected PStmtKey createKey(String sql, int autoGeneratedKeys) {
String catalog = null;
try {
catalog = getCatalog();
} catch (SQLException e) {
// Ignored
}
return new PStmtKey(normalizeSQL(sql), catalog, autoGeneratedKeys);
}
/**
* Create a PStmtKey for the given arguments.
* @param sql the sql string used to define the statement
* @param resultSetType result set type
* @param resultSetConcurrency result set concurrency
*/
protected PStmtKey createKey(String sql, int resultSetType, int resultSetConcurrency) {
String catalog = null;
try {
catalog = getCatalog();
} catch (SQLException e) {
// Ignored
}
return new PStmtKey(normalizeSQL(sql), catalog, resultSetType, resultSetConcurrency);
}
/**
* Create a PStmtKey for the given arguments.
* @param sql the sql string used to define the statement
* @param resultSetType result set type
* @param resultSetConcurrency result set concurrency
* @param stmtType statement type
*/
protected PStmtKey createKey(String sql, int resultSetType, int resultSetConcurrency, StatementType stmtType) {
String catalog = null;
try {
catalog = getCatalog();
} catch (SQLException e) {
// Ignored
}
return new PStmtKey(normalizeSQL(sql), catalog, resultSetType, resultSetConcurrency, stmtType);
}
/**
* Create a PStmtKey for the given arguments.
* @param sql the sql string used to define the statement
*/
protected PStmtKey createKey(String sql) {
String catalog = null;
try {
catalog = getCatalog();
} catch (SQLException e) {
// Ignored
}
return new PStmtKey(normalizeSQL(sql), catalog);
}
/**
* Create a PStmtKey for the given arguments.
* @param sql the SQL string used to define the statement
* @param stmtType statement type
*/
protected PStmtKey createKey(String sql, StatementType stmtType) {
String catalog = null;
try {
catalog = getCatalog();
} catch (SQLException e) {
// Ignored
}
return new PStmtKey(normalizeSQL(sql), catalog, stmtType, null);
}
/**
* Normalize the given SQL statement, producing a
* cannonical form that is semantically equivalent to the original.
*/
protected String normalizeSQL(String sql) {
return sql.trim();
}
/**
* {@link KeyedPooledObjectFactory} method for creating
* {@link PoolablePreparedStatement}s or {@link PoolableCallableStatement}s.
* The stmtType field in the key determines whether
* a PoolablePreparedStatement or PoolableCallableStatement is created.
*
* @param key the key for the {@link PreparedStatement} to be created
* @see #createKey(String, int, int, StatementType)
*/
@Override
public PooledObject makeObject(PStmtKey key)
throws Exception {
if(null == key) {
throw new IllegalArgumentException("Prepared statement key is null or invalid.");
}
if (null == key.getResultSetType() && null == key.getResultSetConcurrency() && null == key.getAutoGeneratedKeys()) {
if (key.getStmtType() == StatementType.PREPARED_STATEMENT ) {
@SuppressWarnings({"rawtypes", "unchecked"}) // Unable to find way to avoid this
PoolablePreparedStatement pps = new PoolablePreparedStatement(
getDelegate().prepareStatement(key.getSql()), key, _pstmtPool, this);
return new DefaultPooledObject(pps);
}
return new DefaultPooledObject(
new PoolableCallableStatement(getDelegate().prepareCall( key.getSql()), key, _pstmtPool, this));
} else if (null == key.getResultSetType() && null == key.getResultSetConcurrency()){
@SuppressWarnings({"rawtypes", "unchecked"}) // Unable to find way to avoid this
PoolablePreparedStatement pps = new PoolablePreparedStatement(
getDelegate().prepareStatement(key.getSql(), key.getAutoGeneratedKeys().intValue()), key, _pstmtPool, this);
return new DefaultPooledObject(pps);
} else { // Both _resultSetType and _resultSetConcurrency are non-null here (both or neither are set by constructors)
if(key.getStmtType() == StatementType.PREPARED_STATEMENT) {
@SuppressWarnings({"rawtypes", "unchecked"}) // Unable to find way to avoid this
PoolablePreparedStatement pps = new PoolablePreparedStatement(getDelegate().prepareStatement(
key.getSql(), key.getResultSetType().intValue(),key.getResultSetConcurrency().intValue()), key, _pstmtPool, this);
return new DefaultPooledObject(pps);
}
return new DefaultPooledObject(
new PoolableCallableStatement( getDelegate().prepareCall(
key.getSql(),key.getResultSetType().intValue(), key.getResultSetConcurrency().intValue()), key, _pstmtPool, this));
}
}
/**
* {@link KeyedPooledObjectFactory} method for destroying
* PoolablePreparedStatements and PoolableCallableStatements.
* Closes the underlying statement.
*
* @param key ignored
* @param p the wrapped pooled statement to be destroyed.
*/
@Override
public void destroyObject(PStmtKey key,
PooledObject p)
throws Exception {
p.getObject().getInnermostDelegate().close();
}
/**
* {@link KeyedPooledObjectFactory} method for validating
* pooled statements. Currently always returns true.
*
* @param key ignored
* @param p ignored
* @return true
*/
@Override
public boolean validateObject(PStmtKey key,
PooledObject p) {
return true;
}
/**
* {@link KeyedPooledObjectFactory} method for activating
* pooled statements.
*
* @param key ignored
* @param p wrapped pooled statement to be activated
*/
@Override
public void activateObject(PStmtKey key,
PooledObject p) throws Exception {
p.getObject().activate();
}
/**
* {@link KeyedPooledObjectFactory} method for passivating
* {@link PreparedStatement}s or {@link CallableStatement}s.
* Invokes {@link PreparedStatement#clearParameters}.
*
* @param key ignored
* @param p a wrapped {@link PreparedStatement}
*/
@Override
public void passivateObject(PStmtKey key,
PooledObject p) throws Exception {
DelegatingPreparedStatement dps = p.getObject();
dps.clearParameters();
dps.passivate();
}
@Override
public String toString() {
if (_pstmtPool != null ) {
return "PoolingConnection: " + _pstmtPool.toString();
}
return "PoolingConnection: null";
}
/**
* The possible statement types.
* @since 2.0
*/
protected static enum StatementType {
CALLABLE_STATEMENT,
PREPARED_STATEMENT
}
}