/*! ******************************************************************************
*
* Pentaho Data Integration
*
* Copyright (C) 2002-2013 by Pentaho : http://www.pentaho.com
*
*******************************************************************************
*
* 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.pentaho.di.core.auth.kerberos;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import javax.security.auth.Subject;
import javax.security.auth.login.LoginContext;
import org.apache.commons.lang.ClassUtils;
public class LoginContextInvocationHandler<T> implements InvocationHandler {
private final T delegate;
private final LoginContext loginContext;
private final Set<Class<?>> interfacesToDelegate;
public LoginContextInvocationHandler( T delegate, LoginContext loginContext ) {
this( delegate, loginContext, new HashSet<Class<?>>() );
}
public LoginContextInvocationHandler( T delegate, LoginContext loginContext, Set<Class<?>> interfacesToDelegate ) {
this.delegate = delegate;
this.loginContext = loginContext;
this.interfacesToDelegate = interfacesToDelegate;
}
@SuppressWarnings( "unchecked" )
public static <T> T forObject( T delegate, LoginContext loginContext, Set<Class<?>> interfacesToDelegate ) {
return (T) Proxy.newProxyInstance( delegate.getClass().getClassLoader(), ( (List<Class<?>>) ClassUtils
.getAllInterfaces( delegate.getClass() ) ).toArray( new Class<?>[] {} ),
new LoginContextInvocationHandler<Object>( delegate, loginContext, interfacesToDelegate ) );
}
@Override
public Object invoke( Object proxy, final Method method, final Object[] args ) throws Throwable {
try {
return Subject.doAs( loginContext.getSubject(), new PrivilegedExceptionAction<Object>() {
@Override
public Object run() throws Exception {
Object result = method.invoke( delegate, args );
if ( result != null ) {
for ( Class<?> iface : result.getClass().getInterfaces() ) {
if ( interfacesToDelegate.contains( iface ) ) {
result = forObject( result, loginContext, interfacesToDelegate );
break;
}
}
}
return result;
}
} );
} catch ( PrivilegedActionException e ) {
if ( e.getCause() instanceof InvocationTargetException ) {
throw ( (InvocationTargetException) e.getCause() ).getCause();
}
throw e;
}
}
}