/*
* Copyright (C) 2006-2013 Bitronix Software (http://www.bitronix.be)
*
* Licensed 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 bitronix.tm.resource.jdbc.proxy;
import java.lang.reflect.Constructor;
import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.HashSet;
import java.util.Set;
import javassist.CannotCompileException;
import javassist.ClassClassPath;
import javassist.ClassMap;
import javassist.ClassPool;
import javassist.CtClass;
import javassist.CtConstructor;
import javassist.CtMethod;
import javassist.CtNewConstructor;
import javassist.CtNewMethod;
import javassist.NotFoundException;
import javax.sql.XAConnection;
import bitronix.tm.resource.jdbc.JdbcPooledConnection;
import bitronix.tm.resource.jdbc.LruStatementCache.CacheKey;
import bitronix.tm.resource.jdbc.lrc.LrcXAResource;
import bitronix.tm.utils.ClassLoaderUtils;
/**
* This class generates JDBC proxy classes using Javassist bytecode generated
* implementations. This is the most efficient proxy factory.
*
* @author Brett Wooldridge
*/
public class JdbcJavassistProxyFactory implements JdbcProxyFactory {
private final ClassMap classMap;
private ClassPool classPool;
private Constructor<Connection> proxyConnectionConstructor;
private Constructor<Statement> proxyStatementConstructor;
private Constructor<CallableStatement> proxyCallableStatementConstructor;
private Constructor<PreparedStatement> proxyPreparedStatementConstructor;
private Constructor<ResultSet> proxyResultSetConstructor;
// For LRC we just use the standard Java Proxies
private final JdbcJavaProxyFactory lrcProxyFactory;
JdbcJavassistProxyFactory() {
classMap = new ClassMap();
ClassPool defaultPool = ClassPool.getDefault();
classPool = new ClassPool(defaultPool);
classPool.insertClassPath(new ClassClassPath(this.getClass()));
classPool.childFirstLookup = true;
createProxyConnectionClass();
createProxyStatementClass();
createProxyCallableStatementClass();
createProxyPreparedStatementClass();
createProxyResultSetClass();
lrcProxyFactory = new JdbcJavaProxyFactory();
// Clear the map, we don't need it anymore
classMap.clear();
classPool = null;
}
/** {@inheritDoc} */
@Override
public Connection getProxyConnection(JdbcPooledConnection jdbcPooledConnection, Connection connection) {
try {
return proxyConnectionConstructor.newInstance(jdbcPooledConnection, connection);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/** {@inheritDoc} */
@Override
public Statement getProxyStatement(JdbcPooledConnection jdbcPooledConnection, Statement statement) {
try {
return proxyStatementConstructor.newInstance(jdbcPooledConnection, statement);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/** {@inheritDoc} */
@Override
public CallableStatement getProxyCallableStatement(JdbcPooledConnection jdbcPooledConnection, CallableStatement statement) {
try {
return proxyCallableStatementConstructor.newInstance(jdbcPooledConnection, statement);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/** {@inheritDoc} */
@Override
public PreparedStatement getProxyPreparedStatement(JdbcPooledConnection jdbcPooledConnection, PreparedStatement statement, CacheKey cacheKey) {
try {
return proxyPreparedStatementConstructor.newInstance(jdbcPooledConnection, statement, cacheKey);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/** {@inheritDoc} */
@Override
public ResultSet getProxyResultSet(Statement statement, ResultSet resultSet) {
try {
return proxyResultSetConstructor.newInstance(statement, resultSet);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/** {@inheritDoc} */
@Override
public XAConnection getProxyXaConnection(Connection connection) {
return lrcProxyFactory.getProxyXaConnection(connection);
}
/** {@inheritDoc} */
@Override
public Connection getProxyConnection(LrcXAResource xaResource, Connection connection) {
return lrcProxyFactory.getProxyConnection(xaResource, connection);
}
// ---------------------------------------------------------------
// Generate Javassist Proxy Classes
// ---------------------------------------------------------------
/**
* Create a proxy class: class ConnectionJavassistProxy extends ConnectionJavaProxy implements java.sql.Connection
*/
private void createProxyConnectionClass() {
try {
Class<Connection> proxyClass = generateProxyClass(Connection.class, ConnectionJavaProxy.class);
proxyConnectionConstructor = proxyClass.getConstructor(new Class<?>[] {JdbcPooledConnection.class, Connection.class} );
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/**
* Create a proxy class: class StatementJavassistProxy extends StatementJavaProxy implements java.sql.Statement
*/
private void createProxyStatementClass() {
try {
Class<Statement> proxyClass = generateProxyClass(Statement.class, StatementJavaProxy.class);
proxyStatementConstructor = proxyClass.getConstructor(new Class<?>[] {JdbcPooledConnection.class, Statement.class});
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/**
* Create a proxy class: class CallableStatementJavassistProxy extends CallableStatementJavaProxy implements java.sql.CallableStatement
*/
private void createProxyCallableStatementClass() {
try {
Class<CallableStatement> proxyClass = generateProxyClass(CallableStatement.class, CallableStatementJavaProxy.class);
proxyCallableStatementConstructor = proxyClass.getConstructor(new Class<?>[] {JdbcPooledConnection.class, CallableStatement.class});
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/**
* Create a proxy class: class PreparedStatementJavassistProxy extends PreparedStatementJavaProxy implements java.sql.PreparedStatement
*/
private void createProxyPreparedStatementClass() {
try {
Class<PreparedStatement> proxyClass = generateProxyClass(PreparedStatement.class, PreparedStatementJavaProxy.class);
proxyPreparedStatementConstructor = proxyClass.getConstructor(new Class<?>[] {JdbcPooledConnection.class, PreparedStatement.class, CacheKey.class});
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/**
* Create a proxy class: class ResultSetJavassistProxy extends ResultSetJavaProxy implements java.sql.ResultSet
*/
private void createProxyResultSetClass() {
try {
Class<ResultSet> proxyClass = generateProxyClass(ResultSet.class, ResultSetJavaProxy.class);
proxyResultSetConstructor = proxyClass.getConstructor(new Class<?>[] {Statement.class, ResultSet.class});
} catch (Exception e) {
throw new RuntimeException(e);
}
}
@SuppressWarnings("unchecked")
private <T> Class<T> generateProxyClass(Class<T> primaryInterface, Class<?> superClass)
throws NotFoundException, CannotCompileException, NoSuchMethodException, SecurityException {
// Make a new class that extends one of the JavaProxy classes (ie. superClass); use the name to XxxJavassistProxy instead of XxxJavaProxy
String superClassName = superClass.getName();
CtClass superClassCt = classPool.getCtClass(superClassName);
CtClass targetCt = classPool.makeClass(superClassName.replace("JavaProxy", "JavassistProxy"), superClassCt);
// Generate constructors that simply call super(..)
for (CtConstructor constructor : superClassCt.getConstructors()) {
CtConstructor ctConstructor = CtNewConstructor.make(constructor.getParameterTypes(), constructor.getExceptionTypes(), targetCt);
targetCt.addConstructor(ctConstructor);
}
// Make a set of method signatures we inherit implementation for, so we don't generate delegates for these
Set<String> superSigs = new HashSet<String>();
for (CtMethod method : superClassCt.getMethods()) {
superSigs.add(method.getName() + method.getSignature());
}
Set<String> methods = new HashSet<String>();
Set<Class<?>> interfaces = ClassLoaderUtils.getAllInterfaces(primaryInterface);
for (Class<?> intf : interfaces) {
CtClass intfCt = classPool.getCtClass(intf.getName());
targetCt.addInterface(intfCt);
for (CtMethod intfMethod : intfCt.getDeclaredMethods()) {
if (superSigs.contains(intfMethod.getName() + intfMethod.getSignature())) {
// don't generate delegates for methods we override
continue;
}
CtMethod method = CtNewMethod.copy(intfMethod, targetCt, classMap);
// Ignore already added methods that come from other interfaces
if (methods.contains(intfMethod.getName() + intfMethod.getSignature())) {
continue;
}
methods.add(intfMethod.getName() + intfMethod.getSignature());
// Generate a method that simply invokes the same method on the delegate
StringBuilder call = new StringBuilder("{");
if ( method.getReturnType() != CtClass.voidType) {
call.append("return ");
}
call.append("((").append(primaryInterface.getName()).append(')'); // cast to primary interface
call.append("delegate).");
call.append(method.getName()).append("($$);");
call.append('}');
method.setBody(call.toString());
targetCt.addMethod(method);
}
}
return targetCt.toClass(ClassLoaderUtils.getClassLoader(), null);
}
}