Java in a Nutshell, 5th Edition [Electronic resources]

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JarInputStreamjava.util.jar

Java 1.2closeable

This class allows a JAR file to be read from an input stream. It extends java.util.ZipInputStream and is used much like that class is used. To create a JarInputStream, simply specify the InputStream from which to read. If you do not want the JarInputStream to attempt to verify any digital signatures contained in the JAR file, pass false as the second argument to the JarInputStream( ) constructor. The JarInputStream( ) constructor first reads the JAR manifest entry, if one exists. The manifest must be the first entry in the JAR file. getManifest( ) returns the Manifest object for the JAR file.

Once you have created a JarInputStream, call getNextJarEntry( ) or getNextEnTRy( ) to obtain the JarEntry or java.util.zip.ZipEntry object that describes the next entry in the JAR file. Then, call a read( ) method (including the inherited versions) to read the contents of that entry. When the stream reaches the end of file, call getNextJarEntry( ) again to start reading the next entry in the file. When all entries have been read from the JAR file, getNextJarEntry( ) and getNextEntry( ) return null.

Figure 16-111. java.util.jar.JarInputStream

public class

JarInputStream extends java.util.zip.ZipInputStream { // Public Constructors public

JarInputStream (java.io.InputStream

in ) throws java.io.IOException; public

JarInputStream (java.io.InputStream

in , boolean

verify ) throws java.io.IOException; // Public Instance Methods public Manifest

getManifest ( ); public JarEntry

getNextJarEntry ( ) throws java.io.IOException; // Public Methods Overriding ZipInputStream public java.util.zip.ZipEntry

getNextEntry ( ) throws java.io.IOException; public int

read (byte[ ]

b , int

off , int

len ) throws java.io.IOException; // Protected Methods Overriding ZipInputStream protected java.util.zip.ZipEntry

createZipEntry (String

name ); }

Passed To

Pack200.Packer.pack( )