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Java example source code file (Utils.java)

This example Java source code file (Utils.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

bufferedoutputstream, com_prefix, ioexception, jar, jarentry, jaroutputstream, noncloser, now, object, pack200, pack200logger, platformlogger, string, threadlocal, util, utils, zip

The Utils.java Java example source code

/*
 * Copyright (c) 2003, 2013, 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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.
 */

package com.sun.java.util.jar.pack;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Collections;
import java.util.Date;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.jar.JarInputStream;
import java.util.jar.JarOutputStream;
import java.util.zip.ZipEntry;
import sun.util.logging.PlatformLogger;

class Utils {
    static final String COM_PREFIX = "com.sun.java.util.jar.pack.";
    static final String METAINF    = "META-INF";

    /*
     * Outputs various diagnostic support information.
     * If >0, print summary comments (e.g., constant pool info).
     * If >1, print unit comments (e.g., processing of classes).
     * If >2, print many comments (e.g., processing of members).
     * If >3, print tons of comments (e.g., processing of references).
     * (installer only)
     */
    static final String DEBUG_VERBOSE = COM_PREFIX+"verbose";

    /*
     * Disables use of native code, prefers the Java-coded implementation.
     * (installer only)
     */
    static final String DEBUG_DISABLE_NATIVE = COM_PREFIX+"disable.native";

    /*
     * Use the default working TimeZone instead of UTC.
     * Note: This has installer unpacker implications.
     * see: zip.cpp which uses gmtime vs. localtime.
     */
    static final String PACK_DEFAULT_TIMEZONE = COM_PREFIX+"default.timezone";

    /*
     * Property indicating that the unpacker should
     * ignore the transmitted PACK_MODIFICATION_TIME,
     * replacing it by the given value. The value can
     * be a numeric string, representing the number of
     * mSecs since the epoch (UTC), or the special string
     * {@link #NOW}, meaning the current time (UTC).
     * The default value is the special string {@link #KEEP},
     * which asks the unpacker to preserve all transmitted
     * modification time information.
     * (installer only)
     */
    static final String UNPACK_MODIFICATION_TIME = COM_PREFIX+"unpack.modification.time";

    /*
     * Property indicating that the unpacker strip the
     * Debug Attributes, if they are present, in the pack stream.
     * The default value is false.
     * (installer only)
     */
    static final String UNPACK_STRIP_DEBUG = COM_PREFIX+"unpack.strip.debug";

    /*
     * Remove the input file after unpacking.
     * (installer only)
     */
    static final String UNPACK_REMOVE_PACKFILE = COM_PREFIX+"unpack.remove.packfile";

    /*
     * A possible value for MODIFICATION_TIME
     */
    static final String NOW                             = "now";
    // Other debug options:
    //   com...debug.bands=false      add band IDs to pack file, to verify sync
    //   com...dump.bands=false       dump band contents to local disk
    //   com...no.vary.codings=false  turn off coding variation heuristics
    //   com...no.big.strings=false   turn off "big string" feature

    /*
     * If this property is set to {@link #TRUE}, the packer will preserve
     * the ordering of class files of the original jar in the output archive.
     * The ordering is preserved only for class-files; resource files
     * may be reordered.
     * <p>
     * If the packer is allowed to reorder class files, it can marginally
     * decrease the transmitted size of the archive.
     */
    static final String PACK_KEEP_CLASS_ORDER = COM_PREFIX+"keep.class.order";
    /*
     * This string PACK200 is given as a zip comment on all JAR files
     * produced by this utility.
     */
    static final String PACK_ZIP_ARCHIVE_MARKER_COMMENT = "PACK200";

    /*
     * behaviour when we hit a class format error, but not necessarily
     * an unknown attribute, by default it is allowed to PASS.
     */
    static final String CLASS_FORMAT_ERROR = COM_PREFIX+"class.format.error";

    // Keep a TLS point to the global data and environment.
    // This makes it simpler to supply environmental options
    // to the engine code, especially the native code.
    static final ThreadLocal<TLGlobals> currentInstance = new ThreadLocal<>();

    // convenience method to access the TL globals
    static TLGlobals getTLGlobals() {
        return currentInstance.get();
    }

    static PropMap currentPropMap() {
        Object obj = currentInstance.get();
        if (obj instanceof PackerImpl)
            return ((PackerImpl)obj).props;
        if (obj instanceof UnpackerImpl)
            return ((UnpackerImpl)obj).props;
        return null;
    }

    static final boolean nolog
        = Boolean.getBoolean(COM_PREFIX+"nolog");

    static final boolean SORT_MEMBERS_DESCR_MAJOR
        = Boolean.getBoolean(COM_PREFIX+"sort.members.descr.major");

    static final boolean SORT_HANDLES_KIND_MAJOR
        = Boolean.getBoolean(COM_PREFIX+"sort.handles.kind.major");

    static final boolean SORT_INDY_BSS_MAJOR
        = Boolean.getBoolean(COM_PREFIX+"sort.indy.bss.major");

    static final boolean SORT_BSS_BSM_MAJOR
        = Boolean.getBoolean(COM_PREFIX+"sort.bss.bsm.major");

    static class Pack200Logger {
        private final String name;
        private PlatformLogger log;
        Pack200Logger(String name) {
            this.name = name;
        }

        private synchronized PlatformLogger getLogger() {
            if (log == null) {
                log = PlatformLogger.getLogger(name);
            }
            return log;
        }

        public void warning(String msg, Object param) {
                getLogger().warning(msg, param);
            }

        public void warning(String msg) {
            warning(msg, null);
        }

        public void info(String msg) {
            int verbose = currentPropMap().getInteger(DEBUG_VERBOSE);
            if (verbose > 0) {
                if (nolog) {
                    System.out.println(msg);
                } else {
                    getLogger().info(msg);
                }
            }
        }

        public void fine(String msg) {
            int verbose = currentPropMap().getInteger(DEBUG_VERBOSE);
            if (verbose > 0) {
                    System.out.println(msg);
            }
        }
    }

    static final Pack200Logger log
        = new Pack200Logger("java.util.jar.Pack200");

    // Returns the Max Version String of this implementation
    static String getVersionString() {
        return "Pack200, Vendor: " +
            System.getProperty("java.vendor") +
            ", Version: " + Constants.MAX_PACKAGE_VERSION;
    }

    static void markJarFile(JarOutputStream out) throws IOException {
        out.setComment(PACK_ZIP_ARCHIVE_MARKER_COMMENT);
    }

    // -0 mode helper
    static void copyJarFile(JarInputStream in, JarOutputStream out) throws IOException {
        if (in.getManifest() != null) {
            ZipEntry me = new ZipEntry(JarFile.MANIFEST_NAME);
            out.putNextEntry(me);
            in.getManifest().write(out);
            out.closeEntry();
        }
        byte[] buffer = new byte[1 << 14];
        for (JarEntry je; (je = in.getNextJarEntry()) != null; ) {
            out.putNextEntry(je);
            for (int nr; 0 < (nr = in.read(buffer)); ) {
                out.write(buffer, 0, nr);
            }
        }
        in.close();
        markJarFile(out);  // add PACK200 comment
    }
    static void copyJarFile(JarFile in, JarOutputStream out) throws IOException {
        byte[] buffer = new byte[1 << 14];
        for (JarEntry je : Collections.list(in.entries())) {
            out.putNextEntry(je);
            InputStream ein = in.getInputStream(je);
            for (int nr; 0 < (nr = ein.read(buffer)); ) {
                out.write(buffer, 0, nr);
            }
        }
        in.close();
        markJarFile(out);  // add PACK200 comment
    }
    static void copyJarFile(JarInputStream in, OutputStream out) throws IOException {
        // 4947205 : Peformance is slow when using pack-effort=0
        out = new BufferedOutputStream(out);
        out = new NonCloser(out); // protect from JarOutputStream.close()
        try (JarOutputStream jout = new JarOutputStream(out)) {
            copyJarFile(in, jout);
        }
    }
    static void copyJarFile(JarFile in, OutputStream out) throws IOException {

        // 4947205 : Peformance is slow when using pack-effort=0
        out = new BufferedOutputStream(out);
        out = new NonCloser(out); // protect from JarOutputStream.close()
        try (JarOutputStream jout = new JarOutputStream(out)) {
            copyJarFile(in, jout);
        }
    }
        // Wrapper to prevent closing of client-supplied stream.
    static private
    class NonCloser extends FilterOutputStream {
        NonCloser(OutputStream out) { super(out); }
        public void close() throws IOException { flush(); }
    }
   static String getJarEntryName(String name) {
        if (name == null)  return null;
        return name.replace(File.separatorChar, '/');
    }

    static String zeString(ZipEntry ze) {
        int store = (ze.getCompressedSize() > 0) ?
            (int)( (1.0 - ((double)ze.getCompressedSize()/(double)ze.getSize()))*100 )
            : 0 ;
        // Follow unzip -lv output
        return ze.getSize() + "\t" + ze.getMethod()
            + "\t" + ze.getCompressedSize() + "\t"
            + store + "%\t"
            + new Date(ze.getTime()) + "\t"
            + Long.toHexString(ze.getCrc()) + "\t"
            + ze.getName() ;
    }



    static byte[] readMagic(BufferedInputStream in) throws IOException {
        in.mark(4);
        byte[] magic = new byte[4];
        for (int i = 0; i < magic.length; i++) {
            // read 1 byte at a time, so we always get 4
            if (1 != in.read(magic, i, 1))
                break;
        }
        in.reset();
        return magic;
    }

    // magic number recognizers
    static boolean isJarMagic(byte[] magic) {
        return (magic[0] == (byte)'P' &&
                magic[1] == (byte)'K' &&
                magic[2] >= 1 &&
                magic[2] <  8 &&
                magic[3] == magic[2] + 1);
    }
    static boolean isPackMagic(byte[] magic) {
        return (magic[0] == (byte)0xCA &&
                magic[1] == (byte)0xFE &&
                magic[2] == (byte)0xD0 &&
                magic[3] == (byte)0x0D);
    }
    static boolean isGZIPMagic(byte[] magic) {
        return (magic[0] == (byte)0x1F &&
                magic[1] == (byte)0x8B &&
                magic[2] == (byte)0x08);
        // fourth byte is variable "flg" field
    }

    private Utils() { } // do not instantiate
}

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