/*
* JBoss, Home of Professional Open Source.
* Copyright 2007, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This 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 (at your option) any later version.
*
* This software 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 software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.as.undertow.session;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.NotSerializableException;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import javax.servlet.http.HttpSessionAttributeListener;
import javax.servlet.http.HttpSessionBindingEvent;
/**
* Diagnostic tool to help identify when non-serializable objects are placed in a web session. To use, place this class on the
* webapp's classpath and add the following to <code>web.xml</code>:
* <p>
* <code><listener><listener-class>org.jboss.as.undertow.session.NonSerializableAttributeTester</listener-class></listener></code>
* </p>
*
* @author <a href="brian.stansberry@jboss.com">Brian Stansberry</a>
* @version $Revision: 82920 $
*/
public class NonSerializableAttributeTester implements HttpSessionAttributeListener {
public NonSerializableAttributeTester() {
super();
}
@Override
public void attributeAdded(HttpSessionBindingEvent event) {
testAttributeSerializability(event.getName(), event.getValue());
}
@Override
public void attributeRemoved(HttpSessionBindingEvent event) {
// do nothing
}
@Override
public void attributeReplaced(HttpSessionBindingEvent event) {
testAttributeSerializability(event.getName(), event.getValue());
}
private void testAttributeSerializability(String name, Object value) {
if (!testSerializability(value)) {
System.out.println(name + " of type " + value.getClass() + " cannot be serialized");
testRecursively(value);
}
}
private boolean testSerializability(Object obj) {
if (obj == null)
return true;
if (!(obj instanceof Serializable)) {
return false;
} else {
ByteArrayOutputStream baos = new ByteArrayOutputStream(1024);
try {
ObjectOutputStream oos = new ObjectOutputStream(baos);
oos.writeObject(obj);
oos.close();
} catch (NotSerializableException io) {
return false;
} catch (IOException io) {
System.out.println("Unexpected IOException");
io.printStackTrace(System.out);
}
}
return true;
}
private void testRecursively(Object obj) {
if (obj instanceof Collection<?>) {
testCollectionSerializability((Collection<?>) obj);
} else if (obj instanceof Map<?, ?>) {
testMapSerializability((Map<?, ?>) obj);
}
}
private void testCollectionSerializability(Collection<?> coll) {
System.out.println("Testing Collection elements");
int i = 0;
for (Iterator<?> iter = coll.iterator(); iter.hasNext(); i++) {
Object obj = iter.next();
if (!(testSerializability(obj))) {
System.out.println("Element " + i + " of type " + obj.getClass() + " cannot be serialized");
testRecursively(obj);
}
}
}
private void testMapSerializability(Map<?, ?> map) {
System.out.println("Testing Map entries");
for (Map.Entry<?, ?> entry : map.entrySet()) {
if (!testSerializability(entry.getKey())) {
System.out.println("Map Key " + entry.getKey() + " of type " + entry.getKey().getClass()
+ " cannot be serialized");
testRecursively(entry.getKey());
} else if (!testSerializability(entry.getValue())) {
System.out.println("Map value under Key " + entry.getKey() + " of type " + entry.getValue().getClass()
+ " cannot be serialized");
testRecursively(entry.getValue());
}
}
}
}