Jar Entry OutputStream : JarFile « File « Java Tutorial






/*
 * The contents of this file are subject to the Sapient Public License
 * Version 1.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 * http://carbon.sf.net/License.html.
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
 * the specific language governing rights and limitations under the License.
 *
 * The Original Code is The Carbon Component Framework.
 *
 * The Initial Developer of the Original Code is Sapient Corporation
 *
 * Copyright (C) 2003 Sapient Corporation. All Rights Reserved.
 */


import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.security.InvalidParameterException;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import java.util.StringTokenizer;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.jar.JarOutputStream;
import java.util.jar.Manifest;
import java.util.zip.ZipEntry;

import sun.rmi.runtime.Log;

/**
 * An output stream that is used by EnhancedJarFile to write entries to a jar.
 * This implementation uses a ByteArrayOutputStream to buffer the output
 * until the stream is closed.  When the stream is closed, the output is written
 * to the jar.
 *
 * Copyright 2002 Sapient
 * @since carbon 1.0
 * @author Douglas Voet, April 2002
 * @version $Revision: 1.9 $($Author: dvoet $ / $Date: 2003/05/05 21:21:23 $)
 */
public class JarEntryOutputStream extends ByteArrayOutputStream {

    private EnhancedJarFile jar;
    private String jarEntryName;

    /**
     * Constructor
     *
     * @param jar the EnhancedJarFile that this instance will write to
     * @param jarEntryName the name of the entry to be written
     */
    public JarEntryOutputStream(
        EnhancedJarFile jar,
        String jarEntryName) {
        super();

        this.jarEntryName = jarEntryName;
        this.jar = jar;
    }

    /**
     * Closes the stream and writes entry to the jar
     */
    public void close() throws IOException {
        writeToJar();
        super.close();
    }

    /**
     * Writes the entry to a the jar file.  This is done by creating a
     * temporary jar file, copying the contents of the existing jar to the
     * temp jar, skipping the entry named by this.jarEntryName if it exists.
     * Then, if the stream was written to, then contents are written as a
     * new entry.  Last, a callback is made to the EnhancedJarFile to
     * swap the temp jar in for the old jar.
     */
    private void writeToJar() throws IOException {

        File jarDir = new File(this.jar.getName()).getParentFile();
        // create new jar
        File newJarFile = File.createTempFile("config", ".jar", jarDir);
        newJarFile.deleteOnExit();
        JarOutputStream jarOutputStream =
            new JarOutputStream(new FileOutputStream(newJarFile));

        try {
            Enumeration entries = this.jar.entries();

            // copy all current entries into the new jar
            while (entries.hasMoreElements()) {
                JarEntry nextEntry = (JarEntry) entries.nextElement();
                // skip the entry named jarEntryName
                if (!this.jarEntryName.equals(nextEntry.getName())) {
                    // the next 3 lines of code are a work around for
                    // bug 4682202 in the java.sun.com bug parade, see:
                    // http://developer.java.sun.com/developer/bugParade/bugs/4682202.html
                    JarEntry entryCopy = new JarEntry(nextEntry);
                    entryCopy.setCompressedSize(-1);
                    jarOutputStream.putNextEntry(entryCopy);

                    InputStream intputStream =
                        this.jar.getInputStream(nextEntry);
                    // write the data
                    for (int data = intputStream.read();
                        data != -1;
                        data = intputStream.read()) {

                        jarOutputStream.write(data);
                    }
                }
            }

            // write the new or modified entry to the jar
            if (size() > 0) {
                jarOutputStream.putNextEntry(new JarEntry(this.jarEntryName));
                jarOutputStream.write(super.buf, 0, size());
                jarOutputStream.closeEntry();
            }
        } finally {
            // close close everything up
            try {
                if (jarOutputStream != null) {
                    jarOutputStream.close();
                }
            } catch (IOException ioe) {
                // eat it, just wanted to close stream
            }
        }

        // swap the jar
        this.jar.swapJars(newJarFile);
    }

}
/*
 * The contents of this file are subject to the Sapient Public License
 * Version 1.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 * http://carbon.sf.net/License.html.
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
 * the specific language governing rights and limitations under the License.
 *
 * The Original Code is The Carbon Component Framework.
 *
 * The Initial Developer of the Original Code is Sapient Corporation
 *
 * Copyright (C) 2003 Sapient Corporation. All Rights Reserved.
 */



/**
 * This class enhances functionality of java.util.jar.JarFile.
 * Additional functionality includes jar entry removal, the ability to list
 * the entries within a directory within the jar, and the ability to get
 * an output stream for modifying extisting entries.
 *
 * @see java.util.jar.JarFile
 *
 * Copyright 2002 Sapient
 * @since carbon 1.0
 * @author Doug Voet, April 2002
 * @version $Revision: 1.11 $ ($Author: dvoet $)
 */
class EnhancedJarFile {
    public static final String JAR_DELIMETER = "/";

 
    private JarFile jar;

    /**
     * @see java.util.jar.JarFile#JarFile(java.lang.String)
     */
    public EnhancedJarFile(String name) throws IOException {

        this.jar = new JarFile(name);
    }

    /**
     * @see java.util.jar.JarFile#JarFile(java.lang.String, boolean)
     */
    public EnhancedJarFile(String name, boolean verify) throws IOException {

        this.jar = new JarFile(name, verify);
    }

    /**
     * @see java.util.jar.JarFile#JarFile(java.io.File)
     */
    public EnhancedJarFile(File file) throws IOException {

        this.jar = new JarFile(file);
    }

    /**
     * @see java.util.jar.JarFile#JarFile(java.io.File, boolean)
     */
    public EnhancedJarFile(File file, boolean verify) throws IOException {

        this.jar = new JarFile(file, verify);
    }

    /**
     * @see java.util.jar.JarFile#JarFile(java.io.File, boolean, int)
     */
    public EnhancedJarFile(File file, boolean verify, int mode)
        throws IOException {

        this.jar = new JarFile(file, verify, mode);
    }

    /**
     * Returns a list of entries that are
     * immediately below the entry named by entryName in the jar's directory
     * structure.
     *
     * @param entryName the name of the directory entry name
     * @return List a list of java.util.jar.JarEntry objects that are
     * immediately below the entry named by entryName in the jar's directory
     * structure.
     */
    public List listSubEntries(String entryName) {
        Enumeration entries = jar.entries();
        List subEntries = new ArrayList();

        while(entries.hasMoreElements()) {
            JarEntry nextEntry = (JarEntry) entries.nextElement();

            if (nextEntry.getName().startsWith(entryName)) {
                // the next entry name starts with the entryName so it
                // is a potential sub entry

                // tokenize the rest of the next entry name to see how
                // many tokens exist
                StringTokenizer tokenizer = new StringTokenizer(
                    nextEntry.getName().substring(entryName.length()),
                    EnhancedJarFile.JAR_DELIMETER);

                if (tokenizer.countTokens() == 1) {
                    // only 1 token exists, so it is a sub-entry
                    subEntries.add(nextEntry);
                }
            }
        }

        return subEntries;
    }

    /**
     * Creates a new output entry stream within the jar.  The entry named
     * will be created if it does not exist within the jar already.
     *
     * @param entryName name of the entry for which to create an output
     * stream.
     * @return JarEntryOutputStream
     */
    public JarEntryOutputStream getEntryOutputStream(String entryName) {
        return new JarEntryOutputStream(this, entryName);
    }

    /**
     * Removes the given entry from the jar.  If the entry does not exist,
     * the method returns without doing anything.
     *
     * @param entry entry to be removed
     * @throws IOException if there is a problem writing the changes
     * to the jar
     */
    public void removeEntry(JarEntry entry) throws IOException {
        // opens an output stream and closes it without writing anything to it
        if (entry != null && getEntry(entry.getName()) != null) {
            JarEntryOutputStream outputStream =
                new JarEntryOutputStream(this, entry.getName());

            outputStream.close();
        }
    }

    /**
     * @see java.util.jar.JarFile#entries()
     */
    public Enumeration entries() {
        return this.jar.entries();
    }

    /**
     * @see java.util.jar.JarFile#getEntry(java.lang.String)
     */
    public ZipEntry getEntry(String arg0) {
        return this.jar.getEntry(arg0);
    }

    /**
     * @see java.util.jar.JarFile#getInputStream(java.util.zip.ZipEntry)
     */
    public InputStream getInputStream(ZipEntry arg0) throws IOException {
        return this.jar.getInputStream(arg0);
    }

    /**
     * @see java.util.jar.JarFile#getJarEntry(java.lang.String)
     */
    public JarEntry getJarEntry(String arg0) {
        return this.jar.getJarEntry(arg0);
    }

    /**
     * @see java.util.jar.JarFile#getManifest()
     */
    public Manifest getManifest() throws IOException {
        return this.jar.getManifest();
    }

    /**
     * @see java.util.zip.ZipFile#close()
     */
    public void close() throws IOException {

        this.jar.close();
    }

    /**
     * @see java.util.zip.ZipFile#getName()
     */
    public String getName() {
        return this.jar.getName();
    }

    /**
     * @see java.util.zip.ZipFile#size()
     */
    public int size() {
        return this.jar.size();
    }

    /**
     * Utility method used to swap the underlying jar file out for the new one.
     * This method closes the old jar file, deletes it, moves the new jar
     * file to the location where the old one used to be and opens it.
     * 
     * This is used when modifying the jar (removal, addition, or changes
     * of entries)
     *
     * @param newJarFile the file object pointing to the new jar file
     */
    void swapJars(File newJarFile) throws IOException {
        File oldJarFile = new File(getName());
        this.jar.close();
        oldJarFile.delete();
        if (newJarFile.renameTo(oldJarFile)) {
            this.jar = new JarFile(oldJarFile);
        } else {
            throw new IOException();
        }
    }
}








11.63.JarFile
11.63.1.Creating a JAR File
11.63.2.Create JarFile and use Pack200.Packer
11.63.3.List all file names in a jar file
11.63.4.Listing the Entries of a JAR File Manifest
11.63.5.Listing the Main Attributes in a JAR File Manifest
11.63.6.Retrieves the manifest from a JAR file and writes the manifest contents to a file.
11.63.7.Get uncompressed and compressed file size in a Jar file
11.63.8.Get zip method: ZipEntry.STORED, ZipEntry.DEFLATED
11.63.9.Get CRC code for each file in a Jar file
11.63.10.Get file comment
11.63.11.Get resource from Jar file
11.63.12.JAR Archives: Jar Lister
11.63.13.JAR Archives: Packer200
11.63.14.JAR Archives: Unpacker200
11.63.15.Jar Entry OutputStream
11.63.16.Get jar file Attribute
11.63.17.Get the jar entry
11.63.18.Get the jar file
11.63.19.Search class in class path and Jar files
11.63.20.Add jar contents to the deployment archive under the given prefix
11.63.21.Manifest Writer
11.63.22.Make Temp Jar
11.63.23.Load resource from Jar file
11.63.24.A class to find resources in the classpath by their mime-type specified in the MANIFEST.