test/jdk/java/lang/reflect/Proxy/nonPublicProxy/NonPublicProxyClass.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
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 *
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 * version 2 for more details (a copy is included in the LICENSE file that
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import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Proxy;
import java.util.*;

/*
 * @test
 * @bug 8004260 8189291
 * @summary Test proxy classes that implement non-public interface
 *
 * @build p.Foo
 * @run main/othervm NonPublicProxyClass
 */
public class NonPublicProxyClass {

    public interface PublicInterface {
        void foo();
    }
    interface NonPublicInterface {
        void bar();
    }

    public static void main(String[] args) throws Exception {
        ClassLoader loader = ClassLoader.getSystemClassLoader();
        Class<?> zipConstantsClass = Class.forName("java.util.zip.ZipConstants", false, null);
        Class<?> fooClass = Class.forName("p.Foo");

        NonPublicProxyClass test1 =
            new NonPublicProxyClass(loader, PublicInterface.class, NonPublicInterface.class);
        NonPublicProxyClass test2 =
            new NonPublicProxyClass(loader, fooClass, PublicInterface.class);
        NonPublicProxyClass test3 =
            new NonPublicProxyClass(null, zipConstantsClass);

        test1.run();
        test2.run();
        test3.run();
    }

    private final ClassLoader loader;
    private final Class<?>[] interfaces;
    private final InvocationHandler handler = newInvocationHandler();
    private Class<?> proxyClass;
    public NonPublicProxyClass(ClassLoader loader, Class<?> ... intfs) {
        this.loader = loader;
        this.interfaces = intfs;
    }

    public void run() throws Exception {
        proxyClass = Proxy.getProxyClass(loader, interfaces);
        if (Modifier.isPublic(proxyClass.getModifiers())) {
            throw new RuntimeException(proxyClass + " must be non-public");
        }
        newProxyInstance();
        newInstanceFromConstructor(proxyClass);
    }

    private void newProxyInstance() {
        // expect newProxyInstance to succeed if it's in the same runtime package
        int i = proxyClass.getName().lastIndexOf('.');
        String pkg = (i != -1) ? proxyClass.getName().substring(0, i) : "";
        Proxy.newProxyInstance(loader, interfaces, handler);
    }

    private void newInstanceFromConstructor(Class<?> proxyClass)
        throws Exception
    {
        // expect newInstance to succeed if it's in the same runtime package
        boolean isSamePackage = proxyClass.getName().lastIndexOf('.') == -1;
        try {
            Constructor cons = proxyClass.getConstructor(InvocationHandler.class);
            cons.newInstance(newInvocationHandler());
            if (!isSamePackage) {
                throw new RuntimeException("ERROR: Constructor.newInstance should not succeed");
            }
        }  catch (IllegalAccessException e) {
            if (isSamePackage) {
                throw e;
            }
        }
    }

    private static InvocationHandler newInvocationHandler() {
        return new InvocationHandler() {
            public Object invoke(Object proxy, Method method, Object[] args)
                    throws Throwable {
                Class<?>[] intfs = proxy.getClass().getInterfaces();
                System.out.println("Proxy for " + Arrays.toString(intfs)
                        + " " + method.getName() + " is being invoked");
                return null;
            }
        };
    }
}