/*

 Copyright (c) 2006, University of Tromsø

 All rights reserved.

 Redistribution and use in source and binary forms, with or without 

 modification, are permitted provided that the following conditions are met:

  * Redistributions of source code must retain the above copyright notice, this list 

    of conditions and the following disclaimer.

  * Redistributions in binary form must reproduce the above copyright notice, this 

    list of conditions and the following disclaimer in the documentation and/or other 

    materials provided with the distribution.

  * Neither the name of the University of Tromsø nor the names of its contributors may 

    be used to endorse or promote products derived from this software without specific 

    prior written permission.

 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY 

 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 

 OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 

 SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 

 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 

 TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 

 BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 

 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 

 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 

 DAMAGE.

 */

 package argos.deploy;

 import java.io.File;

 import java.io.FileInputStream;

 import java.io.IOException;

 import java.util.ArrayList;

 import java.util.Collections;

 import java.util.Enumeration;

 import java.util.List;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import java.util.zip.ZipEntry;

 import java.util.zip.ZipFile;

 import java.util.zip.ZipInputStream;

 /**

  * Created on 30.jun.2006

  * 

  * JarResource: JarResource maps all resources included in a Zip or Jar file. Additionaly, it

  * provides a method to extract one as a blob.

  * 

  * @author Dan Peder Eriksen

  */

 public final class JarResource {

         private static final Logger logger = Logger.getLogger(JarResource.class.getName());

         private List<String> content;

         private File jarFile;

         /**

          * creates a JarResource. It extracts all resources from a Jar into an internal hashtable, keyed

          * by resource names.

          * 

          * @param jarFileName a jar or zip file

          */

         public JarResource(File jarFileName) {

                 super();

                 this.jarFile = jarFileName;

                 content = new ArrayList<String>();

                 init();

         }

         public synchronized void reload() {

                 content.clear();

                 init();

         }

         /**

          * Extracts a jar resource as a blob.

          * 

          * @param name  a resource name.

          */

         public byte[] getResource(String name) {

                 if(hasFile(name)) {

                         byte[] b = null;

                         ZipEntry ze = null;

                         FileInputStream fis = null;

                         ZipInputStream zis = null;

                         try {

                                 fis = new FileInputStream(jarFile);

                                 zis = new ZipInputStream(fis);

                                 while((ze = zis.getNextEntry()) != null) {

                                         if(ze.getName().equals(name)) {

                                                 int size = (int) ze.getSize();

                                                 b = new byte[size];

                                                 int rb = 0;

                                                 int chunk = 0;

                                                 while((size - rb) > 0) {

                                                         chunk = zis.read(b, rb, size - rb);

                                                         if(chunk == -1) {

                                                                 break;

                                                         }

                                                         rb += chunk;

                                                 }

                                                 break;

                                         }

                                 }

                                 zis.close();

                                 fis.close();

                                 return b;

                         }

                         catch (IOException e) {

                                 logger.log(Level.WARNING, "JarResource couldnt read file " + jarFile, e);

                         }

                         finally {

                                 if(zis != null) {

                                         try {

                                                 zis.close();

                                         } catch(IOException ignore) {}

                                 }

                                 if(fis != null) {

                                         try {

                                                 fis.close();

                                         } catch(IOException ignore) {}

                                 }

                         }

                 }

                 return null;

         }

         /**

          * initializes internal hash tables with Jar file resources.

          */

         private void init() {

                 try {

                         ZipFile zf = new ZipFile(jarFile);

                         Enumeration<? extends ZipEntry> e = zf.entries();

                         while(e.hasMoreElements()) {

                                 ZipEntry entry = e.nextElement();

                                 content.add(entry.getName());

                         }

                         zf.close();

                 } catch (IOException e) {

                         logger.log(Level.WARNING, "JarResource couldnt read file " + jarFile, e);

                 }

                 Collections.sort(content);

         }

         public boolean hasFile(String filename) {

                 return Collections.binarySearch(content, filename) >= 0;

         }

         public File getFile() {

                 return jarFile;

         }

 }