/*

 * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

/**

 * @test

 * @library /lib/testlibrary

 * @modules jdk.compiler

 * @build LayerAndLoadersTest CompilerUtils ModuleUtils

 * @run testng LayerAndLoadersTest

 * @summary Tests for java.lang.reflect.Layer@createWithXXX methods

 */

import java.io.IOException;

import java.io.InputStream;

import java.lang.module.Configuration;

import java.lang.module.ModuleDescriptor;

import java.lang.module.ModuleFinder;

import java.lang.module.ModuleReference;

import java.lang.reflect.Layer;

import java.lang.reflect.LayerInstantiationException;

import java.lang.reflect.Method;

import java.lang.reflect.Module;

import java.net.URL;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.util.Enumeration;

import java.util.HashMap;

import java.util.Iterator;

import java.util.Map;

import java.util.Optional;

import java.util.ServiceLoader;

import java.util.Set;

import java.util.stream.Collectors;

import org.testng.annotations.BeforeTest;

import org.testng.annotations.Test;

import static org.testng.Assert.*;

@Test

public class LayerAndLoadersTest {

    private static final String TEST_SRC = System.getProperty("test.src");

    private static final Path SRC_DIR = Paths.get(TEST_SRC, "src");

    private static final Path MODS_DIR = Paths.get("mods");

    @BeforeTest

    public void setup() throws Exception {

        // javac -d mods --module-source-path src src/**

        assertTrue(CompilerUtils.compile(SRC_DIR, MODS_DIR,

                "--module-source-path", SRC_DIR.toString()));

    }

    /**

     * Basic test of Layer defineModulesWithOneLoader

     *

     * Test scenario:

     *   m1 requires m2 and m3

     */

    public void testWithOneLoader() throws Exception {

        ClassLoader scl = ClassLoader.getSystemClassLoader();

        Layer layer = Layer.boot().defineModulesWithOneLoader(cf, scl);

        checkLayer(layer, "m1", "m2", "m3");

        ClassLoader cl1 = layer.findLoader("m1");

        ClassLoader cl2 = layer.findLoader("m2");

        ClassLoader cl3 = layer.findLoader("m3");

        assertTrue(cl1.getParent() == scl);

        assertTrue(cl2 == cl1);

        assertTrue(cl3 == cl1);

        invoke(layer, "m1", "p.Main");

    }

    /**

     * Basic test of Layer defineModulesWithManyLoaders

     *

     * Test scenario:

     *   m1 requires m2 and m3

     */

    public void testWithManyLoaders() throws Exception {

        ClassLoader scl = ClassLoader.getSystemClassLoader();

        Layer layer = Layer.boot().defineModulesWithManyLoaders(cf, scl);

        checkLayer(layer, "m1", "m2", "m3");

        ClassLoader cl1 = layer.findLoader("m1");

        ClassLoader cl2 = layer.findLoader("m2");

        ClassLoader cl3 = layer.findLoader("m3");

        assertTrue(cl1.getParent() == scl);

        assertTrue(cl2.getParent() == scl);

        assertTrue(cl3.getParent() == scl);

        assertTrue(cl2 != cl1);

        assertTrue(cl3 != cl1);

        assertTrue(cl3 != cl2);

        invoke(layer, "m1", "p.Main");

    }

    /**

     * Basic test of Layer defineModulesWithOneLoader where one of the modules

     * is a service provider module.

     *

     * Test scenario:

     *    m1 requires m2 and m3

     *    m1 uses S

     *    m4 provides S with ...

     */

    public void testServicesWithOneLoader() throws Exception {

        ClassLoader scl = ClassLoader.getSystemClassLoader();

        Layer layer = Layer.boot().defineModulesWithOneLoader(cf, scl);

        checkLayer(layer, "m1", "m2", "m3", "m4");

        ClassLoader cl1 = layer.findLoader("m1");

        ClassLoader cl2 = layer.findLoader("m2");

        ClassLoader cl3 = layer.findLoader("m3");

        ClassLoader cl4 = layer.findLoader("m4");

        assertTrue(cl1.getParent() == scl);

        assertTrue(cl2 == cl1);

        assertTrue(cl3 == cl1);

        assertTrue(cl4 == cl1);

        Class<?> serviceType = cl1.loadClass("p.Service");

        assertTrue(serviceType.getClassLoader() == cl1);

        Iterator<?> iter = ServiceLoader.load(serviceType, cl1).iterator();

        Object provider = iter.next();

        assertTrue(serviceType.isInstance(provider));

        assertTrue(provider.getClass().getClassLoader() == cl1);

        assertFalse(iter.hasNext());

    }

    /**

     * Basic test of Layer defineModulesWithManyLoaders where one of the

     * modules is a service provider module.

     *

     * Test scenario:

     *    m1 requires m2 and m3

     *    m1 uses S

     *    m4 provides S with ...

     */

    public void testServicesWithManyLoaders() throws Exception {

        ClassLoader scl = ClassLoader.getSystemClassLoader();

        Layer layer = Layer.boot().defineModulesWithManyLoaders(cf, scl);

        checkLayer(layer, "m1", "m2", "m3", "m4");

        ClassLoader cl1 = layer.findLoader("m1");

        ClassLoader cl2 = layer.findLoader("m2");

        ClassLoader cl3 = layer.findLoader("m3");

        ClassLoader cl4 = layer.findLoader("m4");

        assertTrue(cl1.getParent() == scl);

        assertTrue(cl2.getParent() == scl);

        assertTrue(cl3.getParent() == scl);

        assertTrue(cl4.getParent() == scl);

        assertTrue(cl2 != cl1);

        assertTrue(cl3 != cl1);

        assertTrue(cl3 != cl2);

        assertTrue(cl4 != cl1);

        assertTrue(cl4 != cl2);

        assertTrue(cl4 != cl3);

        Class<?> serviceType = cl1.loadClass("p.Service");

        assertTrue(serviceType.getClassLoader() == cl1);

        // Test that the service provider can be located via any of

        // the class loaders in the layer

        for (Module m : layer.modules()) {

            ClassLoader loader = m.getClassLoader();

            Iterator<?> iter = ServiceLoader.load(serviceType, loader).iterator();

            Object provider = iter.next();

            assertTrue(serviceType.isInstance(provider));

            assertTrue(provider.getClass().getClassLoader() == cl4);

            assertFalse(iter.hasNext());

        }

    }

    /**

     * Tests that the class loaders created by defineModulesWithXXX delegate

     * to the given parent class loader.

     */

    public void testDelegationToParent() throws Exception {

        ClassLoader parent = this.getClass().getClassLoader();

        String cn = this.getClass().getName();

        // one loader

        Layer layer = Layer.boot().defineModulesWithOneLoader(cf, parent);

        testLoad(layer, cn);

         // one loader with boot loader as parent

        layer = Layer.boot().defineModulesWithOneLoader(cf, null);

        testLoadFail(layer, cn);

        // many loaders

        layer = Layer.boot().defineModulesWithManyLoaders(cf, parent);

        testLoad(layer, cn);

        // many loader with boot loader as parent

        layer = Layer.boot().defineModulesWithManyLoaders(cf, null);

        testLoadFail(layer, cn);

    }

    /**

     * Test defineModulesWithXXX when modules that have overlapping packages.

     *

     * Test scenario:

     *   m1 exports p

     *   m2 exports p

     */

    public void testOverlappingPackages() {

        ModuleDescriptor descriptor1

        ModuleDescriptor descriptor2

        ModuleFinder finder = ModuleUtils.finderOf(descriptor1, descriptor2);

        Configuration cf = Layer.boot()

            .configuration()

        // cannot define both module m1 and m2 to the same class loader

        try {

            Layer.boot().defineModulesWithOneLoader(cf, null);

            assertTrue(false);

        } catch (LayerInstantiationException expected) { }

        // should be okay to have one module per class loader

        Layer layer = Layer.boot().defineModulesWithManyLoaders(cf, null);

        checkLayer(layer, "m1", "m2");

    }

    /**

     * Test Layer defineModulesWithXXX with split delegation.

     *

     * Test scenario:

     *   layer1: m1 exports p, m2 exports p

     *   layer2: m3 reads m1, m4 reads m2

     */

    public void testSplitDelegation() {

        ModuleDescriptor descriptor1

        ModuleDescriptor descriptor2

        ModuleFinder finder1 = ModuleUtils.finderOf(descriptor1, descriptor2);

        Configuration cf1 = Layer.boot()

            .configuration()

        Layer layer1 = Layer.boot().defineModulesWithManyLoaders(cf1, null);

        checkLayer(layer1, "m1", "m2");

        ModuleDescriptor descriptor3

        ModuleDescriptor descriptor4

        ModuleFinder finder2 = ModuleUtils.finderOf(descriptor3, descriptor4);

                                                Set.of("m3", "m4"));

        // package p cannot be supplied by two class loaders

        try {

            layer1.defineModulesWithOneLoader(cf2, null);

            assertTrue(false);

        } catch (LayerInstantiationException expected) { }

        // no split delegation when modules have their own class loader

        Layer layer2 = layer1.defineModulesWithManyLoaders(cf2, null);

        checkLayer(layer2, "m3", "m4");

    }

    /**

     * Test Layer defineModulesWithXXX when the modules that override same

     * named modules in the parent layer.

     *

     * Test scenario:

     *   layer1: m1, m2, m3 => same loader

     *   layer2: m1, m2, m4 => same loader

     */

    public void testOverriding1() throws Exception {

        Layer layer1 = Layer.boot().defineModulesWithOneLoader(cf1, null);

        checkLayer(layer1, "m1", "m2", "m3");

        ModuleFinder finder = ModuleFinder.of(MODS_DIR);

                                                Set.of("m1"));

        Layer layer2 = layer1.defineModulesWithOneLoader(cf2, null);

        checkLayer(layer2, "m1", "m2", "m3");

        invoke(layer1, "m1", "p.Main");

        ClassLoader loader1 = layer1.findLoader("m1");

        ClassLoader loader2 = layer1.findLoader("m2");

        ClassLoader loader3 = layer1.findLoader("m3");

        ClassLoader loader4 = layer2.findLoader("m1");

        ClassLoader loader5 = layer2.findLoader("m2");

        ClassLoader loader6 = layer2.findLoader("m3");

        assertTrue(loader1 == loader2);

        assertTrue(loader1 == loader3);

        assertTrue(loader4 == loader5);

        assertTrue(loader4 == loader6);

        assertTrue(loader4 != loader1);

        assertTrue(loader1.loadClass("p.Main").getClassLoader() == loader1);

        assertTrue(loader1.loadClass("q.Hello").getClassLoader() == loader1);

        assertTrue(loader1.loadClass("w.Hello").getClassLoader() == loader1);

        assertTrue(loader4.loadClass("p.Main").getClassLoader() == loader4);

        assertTrue(loader4.loadClass("q.Hello").getClassLoader() == loader4);

        assertTrue(loader4.loadClass("w.Hello").getClassLoader() == loader4);

    }

    /**

     * Test Layer defineModulesWithXXX when the modules that override same

     * named modules in the parent layer.

     *

     * Test scenario:

     *   layer1: m1, m2, m3 => loader pool

     *   layer2: m1, m2, m3 => loader pool

     */

    public void testOverriding2() throws Exception {

        Layer layer1 = Layer.boot().defineModulesWithManyLoaders(cf1, null);

        checkLayer(layer1, "m1", "m2", "m3");

        ModuleFinder finder = ModuleFinder.of(MODS_DIR);

                                                Set.of("m1"));

        Layer layer2 = layer1.defineModulesWithManyLoaders(cf2, null);

        checkLayer(layer2, "m1", "m2", "m3");

        invoke(layer1, "m1", "p.Main");

        ClassLoader loader1 = layer1.findLoader("m1");

        ClassLoader loader2 = layer1.findLoader("m2");

        ClassLoader loader3 = layer1.findLoader("m3");

        ClassLoader loader4 = layer2.findLoader("m1");

        ClassLoader loader5 = layer2.findLoader("m2");

        ClassLoader loader6 = layer2.findLoader("m3");

        assertTrue(loader4 != loader1);

        assertTrue(loader5 != loader2);

        assertTrue(loader6 != loader3);

        assertTrue(loader1.loadClass("p.Main").getClassLoader() == loader1);

        assertTrue(loader1.loadClass("q.Hello").getClassLoader() == loader2);

        assertTrue(loader1.loadClass("w.Hello").getClassLoader() == loader3);

        // p.Main is not visible via loader2

        try {

            loader2.loadClass("p.Main");

            assertTrue(false);

        } catch (ClassNotFoundException expected) { }

        // w.Hello is not visible via loader2

        try {

            loader2.loadClass("w.Hello");

            assertTrue(false);

        } catch (ClassNotFoundException expected) { }

        // p.Main is not visible via loader3

        try {

            loader3.loadClass("p.Main");

            assertTrue(false);

        } catch (ClassNotFoundException expected) { }

        // q.Hello is not visible via loader3

        try {

            loader3.loadClass("q.Hello");

            assertTrue(false);

        } catch (ClassNotFoundException expected) { }

        assertTrue(loader4.loadClass("p.Main").getClassLoader() == loader4);

        assertTrue(loader5.loadClass("q.Hello").getClassLoader() == loader5);

        assertTrue(loader6.loadClass("w.Hello").getClassLoader() == loader6);

        // p.Main is not visible via loader5

        try {

            loader5.loadClass("p.Main");

            assertTrue(false);

        } catch (ClassNotFoundException expected) { }

        // w.Hello is not visible via loader5

        try {

            loader5.loadClass("w.Hello");

            assertTrue(false);

        } catch (ClassNotFoundException expected) { }

        // p.Main is not visible via loader6

        try {

            loader6.loadClass("p.Main");

            assertTrue(false);

        } catch (ClassNotFoundException expected) { }

        // q.Hello is not visible via loader6

        try {

            loader6.loadClass("q.Hello");

            assertTrue(false);

        } catch (ClassNotFoundException expected) { }

    }

    /**

     * Test Layer defineModulesWithXXX when the modules that override same

     * named modules in the parent layer.

     *

     * layer1: m1, m2, m3 => same loader

     * layer2: m1, m3 => same loader

     */

    public void testOverriding3() throws Exception {

        Layer layer1 = Layer.boot().defineModulesWithOneLoader(cf1, null);

        checkLayer(layer1, "m1", "m2", "m3");

        ModuleFinder finder = finderFor("m1", "m3");

                                                Set.of("m1"));

        Layer layer2 = layer1.defineModulesWithOneLoader(cf2, null);

        checkLayer(layer2, "m1", "m3");

        invoke(layer1, "m1", "p.Main");

        ClassLoader loader1 = layer1.findLoader("m1");

        ClassLoader loader2 = layer2.findLoader("m1");

        assertTrue(loader1.loadClass("p.Main").getClassLoader() == loader1);

        assertTrue(loader1.loadClass("q.Hello").getClassLoader() == loader1);

        assertTrue(loader1.loadClass("w.Hello").getClassLoader() == loader1);

        assertTrue(loader2.loadClass("p.Main").getClassLoader() == loader2);

        assertTrue(loader2.loadClass("q.Hello").getClassLoader() == loader1);

        assertTrue(loader2.loadClass("w.Hello").getClassLoader() == loader2);

    }