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 * 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.

 *

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/**

 * @test

 * @modules jdk.zipfs

 * @library /lib/testlibrary

 * @build ModulesInCustomFileSystem JarUtils m1/* m2/*

 * @run testng/othervm ModulesInCustomFileSystem

 * @summary Test ModuleFinder to find modules in a custom file system

 */

import java.io.File;

import java.lang.module.Configuration;

import java.lang.module.ModuleFinder;

import java.lang.module.ModuleReader;

import java.lang.module.ModuleReference;

import java.lang.reflect.Method;

import java.nio.file.FileSystem;

import java.nio.file.FileSystems;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.util.Set;

import org.testng.annotations.Test;

import static org.testng.Assert.*;

@Test

public class ModulesInCustomFileSystem {

    /**

     * Test exploded modules in a JAR file system.

     */

    public void testExplodedModulesInJarFileSystem() throws Exception {

        Path m1 = findModuleDirectory("m1");

        Path m2 = findModuleDirectory("m2");

        Path mlib = m1.getParent();

        assertEquals(mlib, m2.getParent());

        // create JAR file containing m1/** and m2/**

        JarUtils.createJarFile(jar, mlib);

        testJarFileSystem(jar);

    }

    /**

     * Test modular JARs in a JAR file system

     */

    public void testModularJARsInJarFileSystem() throws Exception {

        Path m1 = findModuleDirectory("m1");

        Path m2 = findModuleDirectory("m2");

        JarUtils.createJarFile(contents.resolve("m1.jar"), m1);

        JarUtils.createJarFile(contents.resolve("m2.jar"), m2);

        // create JAR file containing m1.jar and m2.jar

        JarUtils.createJarFile(jar, contents);

        testJarFileSystem(jar);

    }

    /**

     * Opens a JAR file as a file system

     */

    private void testJarFileSystem(Path jar) throws Exception {

        ClassLoader scl = ClassLoader.getSystemClassLoader();

        try (FileSystem fs = FileSystems.newFileSystem(jar, scl)) {

            // ModuleFinder to find modules in top-level directory

            Path top = fs.getPath("/");

            ModuleFinder finder = ModuleFinder.of(top);

            // list the modules

            listAllModules(finder);

            // load modules into child layer, invoking m1/p.Main

            loadAndRunModule(finder);

        }

    }

    /**

     * List all modules that the finder finds and the resources in the module.

     */

    private void listAllModules(ModuleFinder finder) throws Exception {

        for (ModuleReference mref : finder.findAll()) {

            System.out.println(mref.descriptor());

            try (ModuleReader reader = mref.open()) {

                reader.list().forEach(name -> System.out.format("  %s%n", name));

            }

        }

    }

    /**

     * Creates a child layer with m1 and m2, invokes m1/p.Main to ensure that

     * classes can be loaded.

     */

    private void loadAndRunModule(ModuleFinder finder) throws Exception {

        ModuleLayer bootLayer = ModuleLayer.boot();

        Configuration cf = bootLayer.configuration()

                .resolve(finder, ModuleFinder.of(), Set.of("m1"));

        ClassLoader scl = ClassLoader.getSystemClassLoader();

        ModuleLayer layer = bootLayer.defineModulesWithOneLoader(cf, scl);

        Class<?> c = layer.findLoader("m1").loadClass("p.Main");

        Method m = c.getMethod("main", String[].class);

        m.invoke(null, (Object)new String[0]);

    }

    /**

     * Find the directory for a module on the module path

     */

    private Path findModuleDirectory(String name) {

        String mp = System.getProperty("jdk.module.path");

        for (String element : mp.split(File.pathSeparator)) {

            Path dir = Paths.get(element).resolve(name);

            if (Files.exists(dir)) {

                return dir;

            }

        }

        assertFalse(true);

        return null;

    }

}