Java in a Nutshell, 5th Edition

Name

JarFile

Synopsis

This class represents a JAR file and allows the manifest, file list, and individual files to be read from the JAR file. It extends java.util.zip.ZipFile, and its use is similar to that of its superclass. Create a JarFile by specifying a filename or File object. If you do not want JarFile to attempt to verify any digital signatures contained in the JarFile, pass an optional boolean argument of false to the JarFile( ) constructor. As of Java 1.3, temporary JAR files can be automatically deleted when they are closed. To take advantage of this feature, pass ZipFile.OPEN_READ|ZipFile.OPEN_DELETE as the mode argument to the JarFile( ) constructor.

Once you have created a JarFile object, obtain the JAR Manifest with getManifest( ). Obtain an enumeration of the java.util.zip.ZipEntry objects in the file with entries( ). Get the JarEntry for a specified file in the JAR file with getJarEntry( ). To read the contents of a specific entry in the JAR file, obtain the JarEntry or ZipEntry object that represents that entry, pass it to getInputStream( ), and then read until the end of that stream. JarFile does not support the creation of new JAR files or the modification of existing files.

Figure 16-110. java.util.jar.JarFile

public class JarFile extends java.util.zip.ZipFile {
// Public Constructors
     public JarFile(String name) throws java.io.IOException;  
     public JarFile(java.io.File ...