bookExamples.ch15Streams
Class Unzipper

java.lang.Object
  bookExamples.ch15Streams.Unzipper

public final class Unzipper
extends java.lang.Object

JarResources: JarResources maps all resources included in a Zip or Jar file. Additionaly, it provides a method to extract one as a blob.

Field Summary

boolean

debugOn

Constructor Summary

Unzipper(java.io.File jarFileName)
creates a JarResources.

Unzipper(java.lang.String jarFileName)
creates a JarResources.

Method Summary

static boolean	containsResource(java.io.File f, java.lang.String nativeLib)
byte[]	getBlob(java.lang.String name) Extracts a jar resource as a blob.
java.lang.String[]	getNames()
static void	getResourceByName()
static void	main(java.lang.String[] args) Is a test driver.
void	verify()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

debugOn

public boolean debugOn

Constructor Detail

Unzipper

public Unzipper(java.lang.String jarFileName)

creates a JarResources. It extracts all resources from a Jar into an internal hashtable, keyed by resource names.

Parameters:

jarFileName - a jar or zip file

Unzipper

public Unzipper(java.io.File jarFileName)

creates a JarResources. It extracts all resources from a Jar into an internal hashtable, keyed by resource names.

Parameters:

jarFileName - a jar or zip file

Method Detail

getNames

public java.lang.String[] getNames()

getBlob

public byte[] getBlob(java.lang.String name)

Extracts a jar resource as a blob.

Parameters:

name - a resource name.

verify

public void verify()
            throws java.io.IOException

Throws:

java.io.IOException

main

public static void main(java.lang.String[] args)
                 throws java.io.IOException

Is a test driver. Given a jar file and a resource name, it trys to extract the resource and then tells us whether it could or not.

Example Let's say you have a JAR file which jarred up a bunch of gif image files. Now, by using JarResources, you could extract, create, and display those images on-the-fly.

     ...
     JarResources JR=new JarResources("GifBundle.jar");
     Image image=Toolkit.createImage(JR.getResource("logo.gif");
     Image logo=Toolkit.getDefaultToolkit().createImage(
                   JR.getResources("logo.gif")
                   );
     ...
 

Throws:

java.io.IOException

containsResource

public static boolean containsResource(java.io.File f,
                                       java.lang.String nativeLib)

getResourceByName

public static void getResourceByName()