/*
* JBoss, Home of Professional Open Source
* Copyright 2005, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt 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.aop.util;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.security.DigestOutputStream;
import java.security.MessageDigest;
import java.util.HashMap;
import java.util.Map;
import java.util.WeakHashMap;
import org.jboss.aop.util.reference.ConstructorPersistentReference;
import org.jboss.aop.util.reference.MethodPersistentReference;
import org.jboss.aop.util.reference.PersistentReference;
/**
* Create a unique hash for
*
* @author <a href="mailto:marc@jboss.org">Marc Fleury</a>
* @version $Revision: 110623 $
*/
public class MethodHashing
{
// Constants -----------------------------------------------------
// Static --------------------------------------------------------
static Map<Class<?>, Map<String, Long>> methodHashesByName = new WeakHashMap<Class<?>, Map<String, Long>>();
static Map<Class<?>, Map<Long, MethodPersistentReference>> methodHashesByClass = new WeakHashMap<Class<?>, Map<Long, MethodPersistentReference>>();
static Map<Class<?>, Map<Long, ConstructorPersistentReference>> constructorHashesByClass = new WeakHashMap<Class<?>, Map<Long, ConstructorPersistentReference>> ();
public static Method findMethodByHash(Class<?> clazz, long hash) throws Exception
{
return findMethodByHash(clazz, Long.valueOf(hash));
}
public static Method findMethodByHash(Class<?> clazz, Long hash) throws Exception
{
Map<Long, MethodPersistentReference> hashes = getMethodHashes(clazz);
MethodPersistentReference ref = hashes.get(hash);
if (ref != null)
{
return ref.getMethod();
}
if (clazz.isInterface())
{
final Class<?>[] interfaces = clazz.getInterfaces() ;
final int numInterfaces = interfaces.length ;
for(int count = 0 ; count < numInterfaces ; count++)
{
final Method method = findMethodByHash(interfaces[count], hash) ;
if (method != null)
{
return method ;
}
}
}
else if (clazz.getSuperclass() != null)
{
return findMethodByHash(clazz.getSuperclass(), hash);
}
return null;
}
public static Constructor<?> findConstructorByHash(Class<?> clazz, long hash) throws Exception
{
return findConstructorByHash(clazz, Long.valueOf(hash));
}
public static Constructor<?> findConstructorByHash(Class<?> clazz, Long hash) throws Exception
{
Map<Long, ConstructorPersistentReference> hashes = getConstructorHashes(clazz);
ConstructorPersistentReference ref = hashes.get(hash);
if (ref != null)
{
return ref.getConstructor();
}
if (clazz.getSuperclass() != null)
{
return findConstructorByHash(clazz, hash);
}
// Constructor[] cons = SecurityActions.getDeclaredConstructors(clazz);
// for (int i = 0; i < cons.length; i++)
// {
// if (constructorHash(cons[i]) == hash) return cons[i];
// }
// if (clazz.getSuperclass() != null)
// {
// return findConstructorByHash(clazz.getSuperclass(), hash);
// }
return null;
}
public static long methodHash(Method method)
throws Exception
{
Class<?>[] parameterTypes = method.getParameterTypes();
StringBuffer methodDesc = new StringBuffer(method.getName()+"(");
for(int j = 0; j < parameterTypes.length; j++)
{
methodDesc.append(getTypeString(parameterTypes[j]));
}
methodDesc.append(")"+getTypeString(method.getReturnType()));
return createHash(methodDesc.toString());
}
public static long createHash(String methodDesc)
throws Exception
{
long hash = 0;
ByteArrayOutputStream bytearrayoutputstream = new ByteArrayOutputStream(512);
MessageDigest messagedigest = MessageDigest.getInstance("SHA");
DataOutputStream dataoutputstream = new DataOutputStream(new DigestOutputStream(bytearrayoutputstream, messagedigest));
dataoutputstream.writeUTF(methodDesc);
dataoutputstream.flush();
byte abyte0[] = messagedigest.digest();
for(int j = 0; j < Math.min(8, abyte0.length); j++)
hash += (long)(abyte0[j] & 0xff) << j * 8;
return hash;
}
public static long constructorHash(Constructor<?> method)
throws Exception
{
Class<?>[] parameterTypes = method.getParameterTypes();
StringBuffer methodDesc = new StringBuffer(method.getName()+"(");
for(int j = 0; j < parameterTypes.length; j++)
{
methodDesc.append(getTypeString(parameterTypes[j]));
}
methodDesc.append(")");
return createHash(methodDesc.toString());
}
static String getTypeString(Class<?> cl)
{
if (cl == Byte.TYPE)
{
return "B";
} else if (cl == Character.TYPE)
{
return "C";
} else if (cl == Double.TYPE)
{
return "D";
} else if (cl == Float.TYPE)
{
return "F";
} else if (cl == Integer.TYPE)
{
return "I";
} else if (cl == Long.TYPE)
{
return "J";
} else if (cl == Short.TYPE)
{
return "S";
} else if (cl == Boolean.TYPE)
{
return "Z";
} else if (cl == Void.TYPE)
{
return "V";
} else if (cl.isArray())
{
return "["+getTypeString(cl.getComponentType());
} else
{
return "L"+cl.getName().replace('.','/')+";";
}
}
/*
* The use of hashCode is not enough to differenciate methods
* we override the hashCode
*
* The hashes are cached in a static for efficiency
* RO: WeakHashMap needed to support undeploy
*/
public static long calculateHash(Method method)
{
Map<String, Long> methodHashes = methodHashesByName.get(method.getDeclaringClass());
if (methodHashes == null)
{
methodHashes = getInterfaceHashes(method.getDeclaringClass());
// Copy and add
WeakHashMap<Class<?>, Map<String, Long>> newHashMap = new WeakHashMap<Class<?>, Map<String, Long>>();
newHashMap.putAll(methodHashesByName);
newHashMap.put(method.getDeclaringClass(), methodHashes);
methodHashesByName = newHashMap;
}
return methodHashes.get(method.toString()).longValue();
}
/**
* Calculate method hashes. This algo is taken from RMI.
*
* @param intf
* @return
* @deprecated I can't see why this would have any value to anybody apart from this class. It will be made private
*/
public static Map<String, Long> getInterfaceHashes(Class<?> intf)
{
// Create method hashes
Method[] methods = SecurityActions.getDeclaredMethods(intf);
HashMap<String, Long> map = new HashMap<String, Long>();
for (int i = 0; i < methods.length; i++)
{
Method method = methods[i];
try
{
long hash = methodHash(method);
map.put(method.toString(), Long.valueOf(hash));
}
catch (Exception ignore)
{
}
}
return map;
}
private static Map<Long, MethodPersistentReference> getMethodHashes(Class<?> clazz)
{
Map<Long, MethodPersistentReference> methodHashes = methodHashesByClass.get(clazz);
if (methodHashes == null)
{
methodHashes = getMethodHashMap(clazz);
methodHashesByClass.put(clazz, methodHashes);
}
return methodHashes;
}
private static Map<Long, MethodPersistentReference> getMethodHashMap(Class<?> clazz)
{
// Create method hashes
Method[] methods = SecurityActions.getDeclaredMethods(clazz);
HashMap<Long, MethodPersistentReference> map = new HashMap<Long, MethodPersistentReference>();
for (int i = 0; i < methods.length; i++)
{
try
{
long hash = methodHash(methods[i]);
//Use Clebert's Persistent References so we don't get memory leaks
map.put(Long.valueOf(hash), new MethodPersistentReference(methods[i], PersistentReference.REFERENCE_SOFT));
}
catch (Exception ignore)
{
}
}
return map;
}
private static Map<Long, ConstructorPersistentReference> getConstructorHashes(Class<?> clazz)
{
Map<Long, ConstructorPersistentReference> constructorHashes = constructorHashesByClass.get(clazz);
if (constructorHashes == null)
{
constructorHashes = getConstructorHashMap(clazz);
constructorHashesByClass.put(clazz, constructorHashes);
}
return constructorHashes;
}
private static Map<Long, ConstructorPersistentReference> getConstructorHashMap(Class<?> clazz)
{
// Create method hashes
Constructor<?>[] constructors = SecurityActions.getDeclaredConstructors(clazz);
HashMap<Long, ConstructorPersistentReference> map = new HashMap<Long, ConstructorPersistentReference>();
for (int i = 0; i < constructors.length; i++)
{
try
{
long hash = constructorHash(constructors[i]);
//Use Clebert's Persistent References so we don't get memory leaks
map.put(Long.valueOf(hash), new ConstructorPersistentReference(constructors[i], PersistentReference.REFERENCE_SOFT));
}
catch (Exception ignore)
{
}
}
return map;
}
}