org.ow2.easybeans.component.jdbcpool.JStatement Maven / Gradle / Ivy
/**
* EasyBeans
* Copyright (C) 2006 Bull S.A.S.
* Contact: [email protected]
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
* --------------------------------------------------------------------------
* $Id: JStatement.java 2240 2008-01-23 18:39:04Z benoitf $
* --------------------------------------------------------------------------
*/
package org.ow2.easybeans.component.jdbcpool;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import org.ow2.util.log.Log;
import org.ow2.util.log.LogFactory;
/**
* Wrapper on a PreparedStatement. This wrapper is used to track close method in
* order to avoid closing the statement, and putting it instead in a pool.
* @author Philippe Durieux
* @author Florent Benoit
*/
public class JStatement extends AbsProxy {
/**
* Properties of this statement has been changed ? Needs to be be cleared
* when reused.
*/
private boolean changed = false;
/**
* Is that this statement is opened ?
*/
private boolean opened = false;
/**
* Being closed. (in close method).
*/
private boolean closing = false;
/**
* Physical PreparedStatement object on which the wrapper is.
*/
private PreparedStatement ps;
/**
* Managed Connection the Statement belongs to.
*/
private JManagedConnection mc;
/**
* Hashcode computed in constructor.
*/
private int hashCode;
/**
* SQL used as statement.
*/
private String sql;
/**
* Logger.
*/
private Log logger = LogFactory.getLog(JStatement.class);
/**
* Builds a new statement with the given wrapped statement of given
* connection and given sql query.
* @param ps the prepared statement.
* @param mc managed connection
* @param sql query.
*/
public JStatement(final PreparedStatement ps, final JManagedConnection mc, final String sql) {
this.ps = ps;
this.mc = mc;
this.sql = sql;
hashCode = sql.hashCode();
opened = true;
}
/**
* @return Sql query used.
*/
public String getSql() {
return sql;
}
/**
* Gets the preparedstatement used by this wrapper.
* @return the internal prepared statement
*/
protected PreparedStatement getInternalPreparedStatement() {
return this.ps;
}
/**
* @return hashcode of the object
*/
@Override
public int hashCode() {
return hashCode;
}
/**
* @param stmt given statement for comparing it
* @return true if given object is equals to this current object
*/
@Override
public boolean equals(final Object stmt) {
if (stmt == null) {
return false;
}
// different hashcode, cannot be equals
if (this.hashCode != stmt.hashCode()) {
return false;
}
// if got same hashcode, try to see if cast is ok.
if (!(stmt instanceof JStatement)) {
logger.warn("Bad class {0}", stmt);
return false;
}
// Cast object
JStatement psw = (JStatement) stmt;
if (sql == null && psw.getSql() != null) {
return false;
}
if (sql != null && !sql.equals(psw.getSql())) {
return false;
}
try {
if (psw.getInternalPreparedStatement().getResultSetType() != ps.getResultSetType()) {
return false;
}
if (psw.getInternalPreparedStatement().getResultSetConcurrency() != ps.getResultSetConcurrency()) {
return false;
}
} catch (SQLException e) {
logger.warn("Cannot compare statements", e);
return false;
}
logger.debug("Found");
return true;
}
/**
* Processes a method invocation on a proxy instance and returns the result.
* This method will be invoked on an invocation handler when a method is
* invoked on a proxy instance that it is associated with.
* @param proxy the proxy instance that the method was invoked on
* @param method the Method instance corresponding to the
* interface method invoked on the proxy instance.
* @param args an array of objects containing the values of the arguments
* passed in the method invocation on the proxy instance, or
* null if interface method takes no arguments.
* @return the value to return from the method invocation on the proxy
* instance.
* @throws Throwable the exception to throw from the method invocation on
* the proxy instance. The exception's type must be assignable
* either to any of the exception types declared in the
* throws clause of the interface method or to the
* unchecked exception types java.lang.RuntimeException
* or java.lang.Error. If a checked exception is
* thrown by this method that is not assignable to any of the
* exception types declared in the throws clause of
* the interface method, then an UndeclaredThrowableException
* containing the exception that was thrown by this method will be
* thrown by the method invocation on the proxy instance.
*/
public Object invoke(final Object proxy, final Method method, final Object[] args) throws Throwable {
// Methods on the Object.class are not send on the connection impl
if (method.getDeclaringClass().getName().equals("java.lang.Object")) {
return handleObjectMethods(method, args);
}
String methodName = method.getName();
// Methods that are part of the IPreparedStatement interface
if ("forceClose".equals(methodName)) {
return Boolean.valueOf(forceClose());
} else if ("reuse".equals(methodName)) {
reuse();
return null;
} else if ("isClosed".equals(methodName)) {
return Boolean.valueOf(isClosed());
} else if ("forget".equals(methodName)) {
forget();
return null;
} else if ("close".equals(methodName)) {
close();
return null;
}
// If there are some properties changes on the prepared statement, flag them to
// avoid to loose time when resetting it
if ("addBatch".equals(methodName) || "execute".equals(methodName) || "executeUpdate".equals(methodName)
|| "setFetchDirection".equals(methodName) || "setFetchSize".equals(methodName)
|| "setMaxFieldSize".equals(methodName) || "setMaxRows".equals(methodName)
|| "setQueryTimeout".equals(methodName)) {
changed = true;
}
// Delegate to the prepared statement object
try {
return method.invoke(this.ps, args);
} catch (InvocationTargetException e) {
// Throw the inner exception
Throwable targetException = e.getTargetException();
throw targetException;
}
}
/**
* Force a close on the Prepare Statement. Usually, it's the caller that did
* not close it explicitly
* @return true if it was open
*/
public boolean forceClose() {
if (opened) {
logger.debug("Statements should be closed explicitly.");
opened = false;
return true;
}
return false;
}
/**
* Reuses this statement so reset properties.
* @throws SQLException if reset fails
*/
public void reuse() throws SQLException {
ps.clearParameters();
ps.clearWarnings();
opened = true;
if (changed) {
logger.debug("Properties statement have been changed, reset default properties");
ps.clearBatch();
ps.setFetchDirection(ResultSet.FETCH_FORWARD);
ps.setMaxFieldSize(0);
ps.setMaxRows(0);
ps.setQueryTimeout(0);
changed = false;
}
}
/**
* @return true if this statement has been closed, else false.
*/
public boolean isClosed() {
return !opened && !closing;
}
/**
* Physically close this Statement.
* @throws SQLException
*/
public void forget() {
try {
ps.close();
} catch (SQLException e) {
logger.error("Cannot close the PreparedStatement", e);
}
}
/**
* {@inheritDoc}
*/
public void close() throws SQLException {
if (!opened) {
logger.debug("Statement already closed");
return;
}
opened = false;
closing = true;
mc.notifyPsClose(this);
closing = false;
}
}