# ProxyReferenceInvocationHandler.java

    /*
     * Copyright (c) 2007, Rickard Öberg. All Rights Reserved.
     * Copyright (c) 2007, Niclas Hedhman. All Rights Reserved.
     *
     * 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.qi4j.runtime.composite;

    import java.lang.reflect.InvocationHandler;
    import java.lang.reflect.InvocationTargetException;
    import java.lang.reflect.Method;
    import java.lang.reflect.Proxy;
    import java.lang.reflect.UndeclaredThrowableException;
    import org.qi4j.api.composite.CompositeInvoker;

    public final class ProxyReferenceInvocationHandler
        implements InvocationHandler, CompositeInvoker
    {
        private Object proxy;

        public Object proxy()
        {
            return proxy;
        }

        public void setProxy( Object proxy )
        {
            this.proxy = proxy;
        }

        public void clearProxy()
        {
            proxy = null;
        }

        @Override
        public Object invokeComposite( Method method, Object[] args )
            throws Throwable
        {
            try
            {
                InvocationHandler invocationHandler = Proxy.getInvocationHandler( this.proxy );
                return invocationHandler.invoke( this.proxy, method, args );
            }
            catch( InvocationTargetException e )
            {
                throw e.getTargetException();
            }
            catch( UndeclaredThrowableException e )
            {
                throw e.getUndeclaredThrowable();
            }
        }

        @Override
        public Object invoke( Object proxy, Method method, Object[] args )
            throws Throwable
        {
            try
            {
                InvocationHandler invocationHandler = Proxy.getInvocationHandler( this.proxy );
                return invocationHandler.invoke( this.proxy, method, args );
            }
            catch( InvocationTargetException e )
            {
                throw e.getTargetException();
            }
            catch( UndeclaredThrowableException e )
            {
                throw e.getUndeclaredThrowable();
            }
        }
    }