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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.

 *

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

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import java.io.File;

import java.io.IOException;

import java.io.OutputStream;

import java.lang.invoke.MethodHandle;

import java.lang.invoke.MethodHandles;

import java.lang.module.ModuleDescriptor;

import java.lang.reflect.Method;

import java.nio.file.FileSystems;

import java.nio.file.Files;

import java.nio.file.Path;

import java.util.ArrayList;

import java.util.LinkedList;

import java.util.List;

import java.util.jar.Attributes;

import java.util.jar.JarEntry;

import java.util.jar.JarOutputStream;

import java.util.jar.Manifest;

import java.util.stream.Collectors;

import java.util.stream.Stream;

import jdk.internal.module.ModuleInfoWriter;

import jdk.test.lib.JDKToolFinder;

import jdk.test.lib.process.ProcessTools;

import jdk.test.lib.util.JarUtils;

/*

 * @test

 * @bug 8205654

 * @summary Unit test for sun.tools.ProcessHelper class. The test launches Java processes with different Java options

 * and checks that sun.tools.ProcessHelper.getMainClass(pid) method returns a correct main class.                                                                                                                               return a .

 *

 * @requires os.family == "linux"

 * @library /test/lib

 * @modules jdk.jcmd/sun.tools.common:+open

 *          java.base/jdk.internal.module

 * @build test.TestProcess

 * @run main/othervm TestProcessHelper

 */

public class TestProcessHelper {

    private static final String TEST_PROCESS_MAIN_CLASS_NAME = "TestProcess";

    private static final String TEST_PROCESS_MAIN_CLASS_PACKAGE = "test";

    private static final String TEST_PROCESS_MAIN_CLASS = TEST_PROCESS_MAIN_CLASS_PACKAGE + "."

            + TEST_PROCESS_MAIN_CLASS_NAME;

    private static final Path TEST_CLASSES = FileSystems.getDefault().getPath(System.getProperty("test.classes"));

    private static final Path USER_DIR = FileSystems.getDefault().getPath(System.getProperty("user.dir", "."));

    private static final Path TEST_MODULES = USER_DIR.resolve("testmodules");

    private static final String JAVA_PATH = JDKToolFinder.getJDKTool("java");

    private static final Path TEST_CLASS = TEST_CLASSES.resolve(TEST_PROCESS_MAIN_CLASS_PACKAGE)

            .resolve(TEST_PROCESS_MAIN_CLASS_NAME + ".class");

    private static final String[] CP_OPTIONS = {"-cp", "-classpath", "--class-path"};

    private static final String[][] VM_ARGS = {{}, {"-Dtest1=aaa"}, {"-Dtest1=aaa", "-Dtest2=bbb ccc"}};

    private static final String[][] ARGS = {{}, {"param1"}, {"param1", "param2"}};

    private static final String[] MP_OPTIONS = {"-p", "--module-path"};

    private static final String[] MODULE_OPTIONS = {"-m", "--module", "--module="};

    private static final String JAR_OPTION = "-jar";

    private static final String MODULE_NAME = "module1";

    private static final String[][] EXTRA_MODULAR_OPTIONS = {null,

            {"--add-opens", "java.base/java.net=ALL-UNNAMED"},

            {"--add-exports", "java.base/java.net=ALL-UNNAMED"},

            {"--add-reads", "java.base/java.net=ALL-UNNAMED"},

            {"--add-modules", "java.management"},

            {"--limit-modules", "java.management"},

            {"--upgrade-module-path", "test"}};

    private static final String[] PATCH_MODULE_OPTIONS = {"--patch-module", null};

    private static final MethodHandle MH_GET_MAIN_CLASS = resolveMainClassMH();

    private static MethodHandle resolveMainClassMH() {

        try {

            Method getMainClassMethod = Class

                .forName("sun.tools.common.ProcessHelper")

                .getDeclaredMethod("getMainClass", String.class);

            getMainClassMethod.setAccessible(true);

            return MethodHandles.lookup().unreflect(getMainClassMethod);

        } catch (ClassNotFoundException | NoSuchMethodException | SecurityException | IllegalAccessException e) {

            throw new RuntimeException(e);

        }

    }

    private static String callGetMainClass(Process p) {

        try {

            return (String)MH_GET_MAIN_CLASS.invoke(Long.toString(p.pid()));

        } catch (Throwable e) {

            throw new RuntimeException(e);

        }

    }

    public static void main(String[] args) throws Exception {

        new TestProcessHelper().runTests();

    }

    public void runTests() throws Exception {

        testClassPath();

        testJar();

        testModule();

    }

    // Test Java processes that are started with -classpath, -cp, or --class-path options

    // and with different combinations of VM and program args.

    private void testClassPath() throws Exception {

        for (String cp : CP_OPTIONS) {

            for (String[] vma : VM_ARGS) {

                for (String[] arg : ARGS) {

                    for (String[] modularOptions : EXTRA_MODULAR_OPTIONS) {

                        List<String> cmd = new LinkedList<>();

                        cmd.add(JAVA_PATH);

                        cmd.add(cp);

                        cmd.add(TEST_CLASSES.toAbsolutePath().toString());

                        for (String v : vma) {

                            cmd.add(v);

                        }

                        if (modularOptions != null) {

                            cmd.add(modularOptions[0]);

                            cmd.add(modularOptions[1]);

                        }

                        cmd.add(TEST_PROCESS_MAIN_CLASS);

                        for (String a : arg) {

                            cmd.add(a);

                        }

                        testProcessHelper(cmd, TEST_PROCESS_MAIN_CLASS);

                    }

                }

            }

        }

    }

    // Test Java processes that are started with -jar option

    // and with different combinations of VM and program args.

    private void testJar() throws Exception {

        File jarFile = prepareJar();

        for (String[] vma : VM_ARGS) {

            for (String[] arg : ARGS) {

                List<String> cmd = new LinkedList<>();

                cmd.add(JAVA_PATH);

                for (String v : vma) {

                    cmd.add(v);

                }

                cmd.add(JAR_OPTION);

                cmd.add(jarFile.getAbsolutePath());

                for (String a : arg) {

                    cmd.add(a);

                }

                testProcessHelper(cmd, jarFile.getAbsolutePath());

            }

        }

    }

    // Test Java processes that are started with -m or --module options

    // and with different combination of VM and program args.

    private void testModule() throws Exception {

        prepareModule();

        for (String mp : MP_OPTIONS) {

            for (String m : MODULE_OPTIONS) {

                for (String[] vma : VM_ARGS) {

                    for (String[] arg : ARGS) {

                        for(String patchModuleOption : PATCH_MODULE_OPTIONS) {

                            List<String> cmd = new LinkedList<>();

                            cmd.add(JAVA_PATH);

                            cmd.add(mp);

                            cmd.add(TEST_MODULES.toAbsolutePath().toString());

                            if (patchModuleOption != null) {

                                cmd.add(patchModuleOption);

                                cmd.add(MODULE_NAME + "=" + TEST_MODULES.toAbsolutePath().toString());

                            }

                            for (String v : vma) {

                                cmd.add(v);

                            }

                            if (m.endsWith("=")) {

                                cmd.add(m + MODULE_NAME + "/" + TEST_PROCESS_MAIN_CLASS);

                            } else {

                                cmd.add(m);

                                cmd.add(MODULE_NAME + "/" + TEST_PROCESS_MAIN_CLASS);

                            }

                            for (String a : arg) {

                                cmd.add(a);

                            }

                            testProcessHelper(cmd, MODULE_NAME + "/" + TEST_PROCESS_MAIN_CLASS);

                        }

                    }

                }

            }

        }

    }

    private void checkMainClass(Process p, String expectedMainClass) {

        String mainClass = callGetMainClass(p);

        // getMainClass() may return null, e.g. due to timing issues.

        // Attempt some limited retries.

        if (mainClass == null) {

            System.err.println("Main class returned by ProcessHelper was null.");

            // sleep time doubles each round, altogether, wait no longer than 1 sec

            final int MAX_RETRIES = 10;

            int retrycount = 0;

            long sleepms = 1;

            while (retrycount < MAX_RETRIES && mainClass == null) {

                System.err.println("Retry " + retrycount + ", sleeping for " + sleepms + "ms.");

                try {

                    Thread.sleep(sleepms);

                } catch (InterruptedException e) {

                    // ignore

                }

                mainClass = callGetMainClass(p);

                retrycount++;

                sleepms *= 2;

            }

        }

        p.destroyForcibly();

        if (!expectedMainClass.equals(mainClass)) {

            throw new RuntimeException("Main class is wrong: " + mainClass);

        }

    }

    private void testProcessHelper(List<String> args, String expectedValue) throws Exception {

        ProcessBuilder pb = new ProcessBuilder(args);

        String cmd = pb.command().stream().collect(Collectors.joining(" "));

        System.out.println("Starting the process:" + cmd);

        Process p = ProcessTools.startProcess("test", pb);

        if (!p.isAlive()) {

            throw new RuntimeException("Cannot start the process: " + cmd);

        }

        checkMainClass(p, expectedValue);

    }

    private File prepareJar() throws Exception {

        Path jarFile = USER_DIR.resolve("testprocess.jar");

        Manifest manifest = createManifest();

        JarUtils.createJarFile(jarFile, manifest, TEST_CLASSES, TEST_CLASS);

        return jarFile.toFile();

    }

    private void prepareModule() throws Exception {

        TEST_MODULES.toFile().mkdirs();

        Path moduleJar = TEST_MODULES.resolve("mod1.jar");

        ModuleDescriptor md = createModuleDescriptor();

        createModuleJarFile(moduleJar, md, TEST_CLASSES, TEST_CLASS);

    }

    private Manifest createManifest() {

        Manifest manifest = new Manifest();

        manifest.getMainAttributes().put(Attributes.Name.MANIFEST_VERSION, "1.0");

        manifest.getMainAttributes().put(Attributes.Name.MAIN_CLASS, TEST_PROCESS_MAIN_CLASS);

        return manifest;

    }

    private ModuleDescriptor createModuleDescriptor() {

        ModuleDescriptor.Builder builder

                = ModuleDescriptor.newModule(MODULE_NAME).requires("java.base");

        return builder.build();

    }

    private static void createModuleJarFile(Path jarfile, ModuleDescriptor md, Path dir, Path... files)

            throws IOException {

        Path parent = jarfile.getParent();

        if (parent != null) {

            Files.createDirectories(parent);

        }

        List<Path> entries = findAllRegularFiles(dir, files);

        try (OutputStream out = Files.newOutputStream(jarfile);

             JarOutputStream jos = new JarOutputStream(out)) {

            if (md != null) {

                JarEntry je = new JarEntry("module-info.class");

                jos.putNextEntry(je);

                ModuleInfoWriter.write(md, jos);

                jos.closeEntry();

            }

            for (Path entry : entries) {

                String name = toJarEntryName(entry);

                jos.putNextEntry(new JarEntry(name));

                Files.copy(dir.resolve(entry), jos);

                jos.closeEntry();

            }

        }

    }

    private static String toJarEntryName(Path file) {

        Path normalized = file.normalize();

        return normalized.subpath(0, normalized.getNameCount())

                .toString()

                .replace(File.separatorChar, '/');

    }

    private static List<Path> findAllRegularFiles(Path dir, Path[] files) throws IOException {

        List<Path> entries = new ArrayList<>();

        for (Path file : files) {

            try (Stream<Path> stream = Files.find(dir.resolve(file), Integer.MAX_VALUE,

                    (p, attrs) -> attrs.isRegularFile())) {

                stream.map(dir::relativize)

                        .forEach(entries::add);

            }

        }

        return entries;

    }

}