Java example source code file (CompareTest.java)

This example Java source code file (CompareTest.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

arraylist, bufferedreader, constantpoolexception, datainputstream, file, ioexception, jar, jarentry, list, printwriter, set, string, stringbuilder, stringwriter, treeset, util

The CompareTest.java Java example source code

/*
 * Copyright (c) 2009, 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

import java.io.DataInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Enumeration;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

import com.sun.tools.classfile.AccessFlags;
import com.sun.tools.classfile.ClassFile;
import com.sun.tools.classfile.ConstantPoolException;
import com.sun.tools.classfile.Method;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.util.LinkedHashSet;

public class CompareTest {
    String[][] testCases = {
        { },
        { "-jni" },
//        { "-llni" },
    };

    public static void main(String... args) throws Exception {
        new CompareTest().run(args);
    }

    public void run(String... args) throws Exception {
        old_javah_cmd = new File(args[0]);
        rt_jar = new File(args[1]);

        Set<String> testClasses;
        if (args.length > 2) {
            testClasses = new LinkedHashSet<String>(Arrays.asList(Arrays.copyOfRange(args, 2, args.length)));
        } else
            testClasses = getNativeClasses(new JarFile(rt_jar));

        for (String[] options: testCases) {
            for (String name: testClasses) {
                test(Arrays.asList(options), rt_jar, name);
            }
        }

        if (errors == 0)
            System.out.println(count + " tests passed");
        else
            throw new Exception(errors + "/" + count + " tests failed");
    }

    public void test(List<String> options, File bootclasspath, String className)
            throws IOException, InterruptedException {
        System.err.println("test: " + options + " " + className);
        count++;

        testOptions = options;
        testClassName = className;

        File oldOutDir = initDir(file(new File("old"), className));
        int old_rc = old_javah(options, oldOutDir, bootclasspath, className);

        File newOutDir = initDir(file(new File("new"), className));
        int new_rc = new_javah(options, newOutDir, bootclasspath, className);

        if (old_rc != new_rc)
            error("return codes differ; old: " + old_rc + ", new: " + new_rc);

        compare(oldOutDir, newOutDir);
    }

    int old_javah(List<String> options, File outDir, File bootclasspath, String className)
            throws IOException, InterruptedException {
        List<String> cmd = new ArrayList();
        cmd.add(old_javah_cmd.getPath());
        cmd.addAll(options);
        cmd.add("-d");
        cmd.add(outDir.getPath());
        cmd.add("-bootclasspath");
        cmd.add(bootclasspath.getPath());
        cmd.add(className);
        System.err.println("old_javah: " + cmd);
        ProcessBuilder pb = new ProcessBuilder(cmd);
        pb.redirectErrorStream(true);
        Process p = pb.start();
        BufferedReader in = new BufferedReader(new InputStreamReader(p.getInputStream()));
        String line;
        StringBuilder sb = new StringBuilder();
        while ((line = in.readLine()) != null) {
            sb.append(line);
            sb.append("\n");
        }
        System.err.println("old javah out: " + sb.toString());
        return p.waitFor();
    }

    int new_javah(List<String> options, File outDir, File bootclasspath, String className) {
        List<String> args = new ArrayList();
        args.addAll(options);
        args.add("-d");
        args.add(outDir.getPath());
        args.add("-bootclasspath");
        args.add(bootclasspath.getPath());
        args.add(className);
        StringWriter sw = new StringWriter();
        PrintWriter pw = new PrintWriter(sw);
        int rc = com.sun.tools.javah.Main.run(args.toArray(new String[args.size()]), pw);
        pw.close();
        System.err.println("new javah out: " + sw.toString());
        return rc;
    }

    Set<String> getNativeClasses(JarFile jar) throws IOException, ConstantPoolException {
        System.err.println("getNativeClasses: " + jar.getName());
        Set<String> results = new TreeSet();
        Enumeration<JarEntry> e = jar.entries();
        while (e.hasMoreElements()) {
            JarEntry je = e.nextElement();
            if (isNativeClass(jar, je)) {
                String name = je.getName();
                results.add(name.substring(0, name.length() - 6).replace("/", "."));
            }
        }
        return results;
    }

    boolean isNativeClass(JarFile jar, JarEntry entry) throws IOException, ConstantPoolException {
        String name = entry.getName();
        if (name.startsWith("META-INF") || !name.endsWith(".class"))
            return false;
        //String className = name.substring(0, name.length() - 6).replace("/", ".");
        //System.err.println("check " + className);
        InputStream in = jar.getInputStream(entry);
        ClassFile cf = ClassFile.read(in);
        for (int i = 0; i < cf.methods.length; i++) {
            Method m = cf.methods[i];
            if (m.access_flags.is(AccessFlags.ACC_NATIVE)) {
                // System.err.println(className);
                return true;
            }
        }
        return false;
    }

    void compare(File f1, File f2) throws IOException {
        if (f1.isFile() && f2.isFile())
            compareFiles(f1, f2);
        else if (f1.isDirectory() && f2.isDirectory())
            compareDirectories(f1, f2);
        else
            error("files differ: "
                + f1 + " (" + getFileType(f1) + "), "
                + f2 + " (" + getFileType(f2) + ")");
    }

    void compareDirectories(File d1, File d2) throws IOException {
        Set<String> list = new TreeSet();
        list.addAll(Arrays.asList(d1.list()));
        list.addAll(Arrays.asList(d2.list()));
        for (String c: list)
            compare(new File(d1, c), new File(d2, c));
    }

    void compareFiles(File f1, File f2) throws IOException {
        byte[] c1 = readFile(f1);
        byte[] c2 = readFile(f2);
        if (!Arrays.equals(c1, c2))
            error("files differ: " + f1 + ", " + f2);
    }

    byte[] readFile(File file) throws IOException {
        int size = (int) file.length();
        byte[] data = new byte[size];
        DataInputStream in = new DataInputStream(new FileInputStream(file));
        try {
            in.readFully(data);
        } finally {
            in.close();
        }
        return data;
    }

    String getFileType(File f) {
        return f.isDirectory() ? "directory"
                : f.isFile() ? "file"
                : f.exists() ? "other"
                : "not found";
    }

    /**
     * Set up an empty directory.
     */
    public File initDir(File dir) {
        if (dir.exists())
            deleteAll(dir);
        dir.mkdirs();
        return dir;
    }

    /**
     * Delete a file or a directory (including all its contents).
     */
    boolean deleteAll(File file) {
        if (file.isDirectory()) {
            for (File f: file.listFiles())
                deleteAll(f);
        }
        return file.delete();
    }

    File file(File dir, String... path) {
        File f = dir;
        for (String p: path)
            f = new File(f, p);
        return f;
    }

    /**
     * Report an error.
     */
    void error(String msg, String... more) {
        System.err.println("test: " + testOptions + " " + testClassName);
        System.err.println("error: " + msg);
        for (String s: more)
            System.err.println(s);
        errors++;
        System.exit(1);
    }

    File old_javah_cmd;
    File rt_jar;
    List<String> testOptions;
    String testClassName;
    int count;
    int errors;
}