org.springframework.ldap.core.support.SingleContextSource Maven / Gradle / Ivy
/*
* Copyright 2005-2010 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.ldap.core.support;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import javax.naming.directory.DirContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.ldap.NamingException;
import org.springframework.ldap.core.ContextSource;
import org.springframework.ldap.core.DirContextProxy;
import org.springframework.ldap.support.LdapUtils;
import org.springframework.beans.factory.DisposableBean;
/**
* A {@link ContextSource} to be used as a decorator around a target ContextSource
* to make sure the target is never actually closed. Useful when working with e.g. paged results,
* as these require the same target to be used.
*
* @author Mattias Hellborg Arthursson
*/
public class SingleContextSource implements ContextSource, DisposableBean {
private static final Log log = LogFactory.getLog(SingleContextSource.class);
private final DirContext ctx;
/**
* Constructor.
*
* @param ctx the target DirContext.
*/
public SingleContextSource(DirContext ctx) {
this.ctx = ctx;
}
/*
* @see org.springframework.ldap.ContextSource#getReadOnlyContext()
*/
public DirContext getReadOnlyContext() throws NamingException {
return getNonClosingDirContextProxy(ctx);
}
/*
* @see org.springframework.ldap.ContextSource#getReadWriteContext()
*/
public DirContext getReadWriteContext() throws NamingException {
return getNonClosingDirContextProxy(ctx);
}
private DirContext getNonClosingDirContextProxy(DirContext context) {
return (DirContext) Proxy.newProxyInstance(DirContextProxy.class
.getClassLoader(), new Class[]{
LdapUtils.getActualTargetClass(context),
DirContextProxy.class},
new SingleContextSource.NonClosingDirContextInvocationHandler(
context));
}
public DirContext getContext(String principal, String credentials)
throws NamingException {
throw new UnsupportedOperationException(
"Not a valid operation for this type of ContextSource");
}
/**
* Destroy method that allows the target DirContext to be cleaned up when
* the SingleContextSource is not going to be used any more.
*/
public void destroy() {
try {
ctx.close();
}
catch (javax.naming.NamingException e) {
log.warn(e);
}
}
/**
* A proxy for DirContext forwarding all operation to the target DirContext,
* but making sure that no close
operations will be performed.
*
* @author Mattias Hellborg Arthursson
*/
public static class NonClosingDirContextInvocationHandler implements
InvocationHandler {
private DirContext target;
public NonClosingDirContextInvocationHandler(DirContext target) {
this.target = target;
}
/*
* @see java.lang.reflect.InvocationHandler#invoke(java.lang.Object,
* java.lang.reflect.Method, java.lang.Object[])
*/
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable {
String methodName = method.getName();
if (methodName.equals("getTargetContext")) {
return target;
} else if (methodName.equals("equals")) {
// Only consider equal when proxies are identical.
return (proxy == args[0] ? Boolean.TRUE : Boolean.FALSE);
} else if (methodName.equals("hashCode")) {
// Use hashCode of Connection proxy.
return new Integer(proxy.hashCode());
} else if (methodName.equals("close")) {
// Never close the target context, as this class will only be
// used for operations concerning the compensating transactions.
return null;
}
try {
return method.invoke(target, args);
}
catch (InvocationTargetException e) {
throw e.getTargetException();
}
}
}
}