001/*
002 * JDrupes Builder
003 * Copyright (C) 2025 Michael N. Lipp
004 * 
005 * This program is free software: you can redistribute it and/or modify
006 * it under the terms of the GNU Affero General Public License as
007 * published by the Free Software Foundation, either version 3 of the
008 * License, or (at your option) any later version.
009 *
010 * This program is distributed in the hope that it will be useful,
011 * but WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
013 * GNU Affero General Public License for more details.
014 *
015 * You should have received a copy of the GNU Affero General Public License
016 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
017 */
018
019package org.jdrupes.builder.core;
020
021import java.lang.reflect.InvocationHandler;
022import java.lang.reflect.Method;
023import java.lang.reflect.Proxy;
024import org.jdrupes.builder.api.Proxyable;
025
026/// A [InvocationHandler] that simply forwards all invocations to the
027/// proxied object.
028///
029public class ForwardingHandler implements InvocationHandler {
030
031    private final Object proxied;
032
033    /// Instantiates a new forwarding handler.
034    ///
035    /// @param proxied the proxied object
036    ///
037    public ForwardingHandler(Object proxied) {
038        this.proxied = proxied;
039    }
040
041    @Override
042    public Object invoke(Object proxy, Method method, Object[] args)
043            throws Throwable {
044        if ("equals".equals(method.getName())
045            && Proxy.isProxyClass(args[0].getClass())
046            && args[0] instanceof Proxyable other) {
047            return method.invoke(proxied, other.backing());
048        }
049        return method.invoke(proxied, args);
050    }
051
052}