org.springframework.jdbc.datasource.WebSphereDataSourceAdapter Maven / Gradle / Ivy
/*
* Copyright 2002-2018 the original author or authors.
*
* 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 org.springframework.jdbc.datasource;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.sql.Connection;
import java.sql.SQLException;
import javax.sql.DataSource;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ReflectionUtils;
import org.springframework.util.StringUtils;
/**
* {@link DataSource} implementation that delegates all calls to a WebSphere
* target {@link DataSource}, typically obtained from JNDI, applying a current
* isolation level and/or current user credentials to every Connection obtained
* from it.
*
* Uses IBM-specific API to get a JDBC Connection with a specific isolation
* level (and read-only flag) from a WebSphere DataSource
* (IBM code example).
* Supports the transaction-specific isolation level exposed by
* {@link org.springframework.transaction.support.TransactionSynchronizationManager#getCurrentTransactionIsolationLevel()}.
* It's also possible to specify a default isolation level, to be applied when the
* current Spring-managed transaction does not define a specific isolation level.
*
*
Usage example, defining the target DataSource as an inner-bean JNDI lookup
* (of course, you can link to any WebSphere DataSource through a bean reference):
*
*
* <bean id="myDataSource" class="org.springframework.jdbc.datasource.WebSphereDataSourceAdapter">
* <property name="targetDataSource">
* <bean class="org.springframework.jndi.JndiObjectFactoryBean">
* <property name="jndiName" value="jdbc/myds"/>
* </bean>
* </property>
* </bean>
*
* Thanks to Ricardo Olivieri for submitting the original implementation
* of this approach!
*
* @author Juergen Hoeller
* @author Lari Hotari
* @author Ricardo N. Olivieri
* @since 2.0.3
* @see com.ibm.websphere.rsadapter.JDBCConnectionSpec
* @see com.ibm.websphere.rsadapter.WSDataSource#getConnection(com.ibm.websphere.rsadapter.JDBCConnectionSpec)
* @see org.springframework.transaction.support.TransactionSynchronizationManager#getCurrentTransactionIsolationLevel()
* @see org.springframework.transaction.support.TransactionSynchronizationManager#isCurrentTransactionReadOnly()
*/
public class WebSphereDataSourceAdapter extends IsolationLevelDataSourceAdapter {
protected final Log logger = LogFactory.getLog(getClass());
private Class wsDataSourceClass;
private Method newJdbcConnSpecMethod;
private Method wsDataSourceGetConnectionMethod;
private Method setTransactionIsolationMethod;
private Method setReadOnlyMethod;
private Method setUserNameMethod;
private Method setPasswordMethod;
/**
* This constructor retrieves the WebSphere JDBC connection spec API,
* so we can get obtain specific WebSphere Connections using reflection.
*/
public WebSphereDataSourceAdapter() {
try {
this.wsDataSourceClass = getClass().getClassLoader().loadClass("com.ibm.websphere.rsadapter.WSDataSource");
Class jdbcConnSpecClass = getClass().getClassLoader().loadClass("com.ibm.websphere.rsadapter.JDBCConnectionSpec");
Class wsrraFactoryClass = getClass().getClassLoader().loadClass("com.ibm.websphere.rsadapter.WSRRAFactory");
this.newJdbcConnSpecMethod = wsrraFactoryClass.getMethod("createJDBCConnectionSpec");
this.wsDataSourceGetConnectionMethod =
this.wsDataSourceClass.getMethod("getConnection", jdbcConnSpecClass);
this.setTransactionIsolationMethod =
jdbcConnSpecClass.getMethod("setTransactionIsolation", int.class);
this.setReadOnlyMethod = jdbcConnSpecClass.getMethod("setReadOnly", Boolean.class);
this.setUserNameMethod = jdbcConnSpecClass.getMethod("setUserName", String.class);
this.setPasswordMethod = jdbcConnSpecClass.getMethod("setPassword", String.class);
}
catch (Exception ex) {
throw new IllegalStateException(
"Could not initialize WebSphereDataSourceAdapter because WebSphere API classes are not available: " + ex);
}
}
/**
* Checks that the specified 'targetDataSource' actually is
* a WebSphere WSDataSource.
*/
@Override
public void afterPropertiesSet() {
super.afterPropertiesSet();
if (!this.wsDataSourceClass.isInstance(getTargetDataSource())) {
throw new IllegalStateException(
"Specified 'targetDataSource' is not a WebSphere WSDataSource: " + getTargetDataSource());
}
}
/**
* Builds a WebSphere JDBCConnectionSpec object for the current settings
* and calls {@code WSDataSource.getConnection(JDBCConnectionSpec)}.
* @see #createConnectionSpec
* @see com.ibm.websphere.rsadapter.WSDataSource#getConnection(com.ibm.websphere.rsadapter.JDBCConnectionSpec)
*/
@Override
protected Connection doGetConnection(@Nullable String username, @Nullable String password) throws SQLException {
// Create JDBCConnectionSpec using current isolation level value and read-only flag.
Object connSpec = createConnectionSpec(
getCurrentIsolationLevel(), getCurrentReadOnlyFlag(), username, password);
if (logger.isDebugEnabled()) {
logger.debug("Obtaining JDBC Connection from WebSphere DataSource [" +
getTargetDataSource() + "], using ConnectionSpec [" + connSpec + "]");
}
// Create Connection through invoking WSDataSource.getConnection(JDBCConnectionSpec)
Connection con = (Connection) invokeJdbcMethod(
this.wsDataSourceGetConnectionMethod, obtainTargetDataSource(), connSpec);
Assert.state(con != null, "No Connection");
return con;
}
/**
* Create a WebSphere {@code JDBCConnectionSpec} object for the given characteristics.
* The default implementation uses reflection to apply the given settings.
* Can be overridden in subclasses to customize the JDBCConnectionSpec object
* (JDBCConnectionSpec javadoc;
* IBM developerWorks article).
* @param isolationLevel the isolation level to apply (or {@code null} if none)
* @param readOnlyFlag the read-only flag to apply (or {@code null} if none)
* @param username the username to apply ({@code null} or empty indicates the default)
* @param password the password to apply (may be {@code null} or empty)
* @throws SQLException if thrown by JDBCConnectionSpec API methods
* @see com.ibm.websphere.rsadapter.JDBCConnectionSpec
*/
protected Object createConnectionSpec(@Nullable Integer isolationLevel, @Nullable Boolean readOnlyFlag,
@Nullable String username, @Nullable String password) throws SQLException {
Object connSpec = invokeJdbcMethod(this.newJdbcConnSpecMethod, null);
Assert.state(connSpec != null, "No JDBCConnectionSpec");
if (isolationLevel != null) {
invokeJdbcMethod(this.setTransactionIsolationMethod, connSpec, isolationLevel);
}
if (readOnlyFlag != null) {
invokeJdbcMethod(this.setReadOnlyMethod, connSpec, readOnlyFlag);
}
// If the username is empty, we'll simply let the target DataSource
// use its default credentials.
if (StringUtils.hasLength(username)) {
invokeJdbcMethod(this.setUserNameMethod, connSpec, username);
invokeJdbcMethod(this.setPasswordMethod, connSpec, password);
}
return connSpec;
}
@Nullable
private static Object invokeJdbcMethod(Method method, @Nullable Object target, @Nullable Object... args)
throws SQLException {
try {
return method.invoke(target, args);
}
catch (IllegalAccessException ex) {
ReflectionUtils.handleReflectionException(ex);
}
catch (InvocationTargetException ex) {
if (ex.getTargetException() instanceof SQLException) {
throw (SQLException) ex.getTargetException();
}
ReflectionUtils.handleInvocationTargetException(ex);
}
throw new IllegalStateException("Should never get here");
}
}