/*

 * Copyright (c) 2014, 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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import java.lang.module.ModuleDescriptor.Exports;

import java.lang.module.ResolvedModule;

import java.lang.reflect.Layer;

import java.lang.reflect.Module;

import java.util.function.Predicate;

import java.util.stream.Stream;

import org.testng.annotations.Test;

import static org.testng.Assert.*;

/*

 * @test

 * @summary Basic test of java.lang.reflect.Module

 * @modules java.desktop java.xml

 * @run testng BasicModuleTest

 */

public class BasicModuleTest {

    /**

     * Tests that the given module reads all modules in the boot Layer.

     */

    private void testReadsAllBootModules(Module m) {

        Layer bootLayer = Layer.boot();

        bootLayer.configuration()

            .modules()

            .stream()

            .map(ResolvedModule::name)

            .map(bootLayer::findModule)

            .forEach(target -> assertTrue(m.canRead(target.get())));

    }

    /**

     * Returns {@code true} if the array contains the given object.

     */

    private <T> boolean contains(T[] array, T obj) {

        return Stream.of(array).anyMatch(obj::equals);

    }

    /**

     * Returns a {@code Predicate} to test if a package is exported.

     */

    private Predicate<Exports> doesExport(String pn) {

        return e -> (e.source().equals(pn) && !e.isQualified());

    }

    @Test

    public void testThisModule() {

        Module thisModule = BasicModuleTest.class.getModule();

        Module baseModule = Object.class.getModule();

        assertFalse(thisModule.isNamed());

        assertTrue(thisModule.getName() == null);

        assertTrue(thisModule.getDescriptor() == null);

        assertTrue(thisModule.getLayer() == null);

        assertTrue(thisModule.toString().startsWith("unnamed module "));

        ClassLoader thisLoader = BasicModuleTest.class.getClassLoader();

        assertTrue(thisLoader == thisModule.getClassLoader());

        assertTrue(thisLoader.getUnnamedModule() == thisModule);

        // unnamed modules read all other modules

        ClassLoader cl;

        cl = ClassLoader.getPlatformClassLoader();

        assertTrue(thisModule.canRead(cl.getUnnamedModule()));

        cl = ClassLoader.getSystemClassLoader();

        assertTrue(thisModule.canRead(cl.getUnnamedModule()));

        testReadsAllBootModules(thisModule);

        // unnamed modules export all packages

        assertTrue(thisModule.isExported(""));

        assertTrue(thisModule.isExported("", thisModule));

        assertTrue(thisModule.isExported("", baseModule));

        assertTrue(thisModule.isExported("p"));

        assertTrue(thisModule.isExported("p", thisModule));

        assertTrue(thisModule.isExported("p", baseModule));

        // this test is in the unnamed package

        assertTrue(contains(thisModule.getPackages(), ""));

    }

    @Test

    public void testUnnamedModules() {

        Module thisModule = BasicModuleTest.class.getModule();

        Module baseModule = Object.class.getModule();

        ClassLoader loader1 = ClassLoader.getSystemClassLoader();

        ClassLoader loader2 = loader1.getParent();

        Module m1 = loader1.getUnnamedModule();

        Module m2 = loader2.getUnnamedModule();

        assertTrue(m1 != m2);

        assertFalse(m1.isNamed());

        assertFalse(m2.isNamed());

        assertTrue(m1.getLayer() == null);

        assertTrue(m2.getLayer() == null);

        assertTrue(m1.toString().startsWith("unnamed module "));

        assertTrue(m2.toString().startsWith("unnamed module "));

        // unnamed module reads all modules

        assertTrue(m1.canRead(m2));

        assertTrue(m2.canRead(m1));

        testReadsAllBootModules(m1);

        testReadsAllBootModules(m2);

        assertTrue(m1.isExported(""));

        assertTrue(m1.isExported("", thisModule));

        assertTrue(m1.isExported("", baseModule));

        assertTrue(m1.isExported("p"));

        assertTrue(m1.isExported("p", thisModule));

        assertTrue(m1.isExported("p", baseModule));

    }

    @Test

    public void testBaseModule() {

        Module base = Object.class.getModule();

        Module thisModule = BasicModuleTest.class.getModule();

        // getName

        assertTrue(base.getName().equals("java.base"));

        // getDescriptor

        assertTrue(base.getDescriptor().exports().stream()

                .anyMatch(doesExport("java.lang")));

        // getClassLoader

        assertTrue(base.getClassLoader() == null);

        // getLayer

        assertTrue(base.getLayer() == Layer.boot());

        // toString

        assertEquals(base.toString(), "module java.base");

        // getPackages

        assertTrue(contains(base.getPackages(), "java.lang"));

        // canRead

        assertTrue(base.canRead(base));

        // isExported

        assertTrue(base.isExported("java.lang"));

        assertTrue(base.isExported("java.lang", thisModule));

        assertFalse(base.isExported("java.wombat"));

        assertFalse(base.isExported("java.wombat", thisModule));

    }

    @Test

    public void testDesktopModule() {

        Module desktop = java.awt.Component.class.getModule();

        Module base = Object.class.getModule();

        Module xml = javax.xml.XMLConstants.class.getModule();

        Module thisModule = BasicModuleTest.class.getModule();

        // name

        assertTrue(desktop.getName().equals("java.desktop"));

        // descriptor

        assertTrue(desktop.getDescriptor().exports().stream()

                   .anyMatch(doesExport("java.awt")));

        // getClassLoader

        assertTrue(desktop.getClassLoader() == null);

        // getLayer

        assertTrue(desktop.getLayer() == Layer.boot());

        // toString

        assertEquals(desktop.toString(), "module java.desktop");

        // getPackages

        assertTrue(contains(desktop.getPackages(), "java.awt"));

        assertTrue(contains(desktop.getPackages(), "sun.awt"));

        // canRead

        assertTrue(desktop.canRead(base));

        assertTrue(desktop.canRead(xml));

        // isExported

        assertTrue(desktop.isExported("java.awt"));

        assertTrue(desktop.isExported("java.awt", thisModule));

        assertFalse(desktop.isExported("java.wombat"));

        assertFalse(desktop.isExported("java.wombat", thisModule));

    }

    @Test(expectedExceptions = { NullPointerException.class })

    public void testIsExportedNull() {

        Module thisModule = this.getClass().getModule();

        thisModule.isExported(null, thisModule);

    }

    @Test(expectedExceptions = { NullPointerException.class })

    public void testIsExportedToNull() {

        Module thisModule = this.getClass().getModule();

        thisModule.isExported("", null);

    }

}