org.apache.geronimo.jcache.simple.ExceptionWrapperHandler Maven / Gradle / Ivy

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.geronimo.jcache.simple;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

public class ExceptionWrapperHandler implements InvocationHandler {

    private final T delegate;

    private final Constructor wrapper;

    public ExceptionWrapperHandler(final T delegate, final Class exceptionType) {
        this.delegate = delegate;
        try {
            this.wrapper = exceptionType.getConstructor(Throwable.class);
        } catch (final NoSuchMethodException e) {
            throw new IllegalStateException(e);
        }
    }

    @Override
    public Object invoke(final Object proxy, final Method method, final Object[] args) throws Throwable {
        if (AutoCloseable.class == method.getDeclaringClass() && !AutoCloseable.class.isInstance(delegate)) {
            return null;
        }
        try {
            return method.invoke(delegate, args);
        } catch (final InvocationTargetException ite) {
            final Throwable e = ite.getCause();
            if (RuntimeException.class.isInstance(e)) {
                final RuntimeException re;
                try {
                    re = wrapper.newInstance(e);
                } catch (final Exception e1) {
                    throw new IllegalArgumentException(e1);
                }
                throw re;
            }
            throw e;
        }
    }

    public static  T newProxy(final ClassLoader loader, final T delegate,
            final Class exceptionType, final Class apis) {
        return (T) Proxy.newProxyInstance(loader, new Class[] { apis, AutoCloseable.class },
                new ExceptionWrapperHandler<>(delegate, exceptionType));
    }
}