Extracting .jar file with command line

Question

I am trying to extract the files from a .jar file. How do I do that using command line?

I am running Windows 7

Answer 1

Java has a class specifically for zip files and one even more specifically for Jar Files.

java.util.jar.JarOutputStream
java.util.jar.JarInputStream

using those you could, on a command from the console, using a scanner set to system.in

Scanner console = new Scanner(System.in);
String input = console.nextLine();

then get all the components and write them as a file.

JarEntry JE = null;
while((JE = getNextJarEntry()) != null)
{
    //do stuff with JE
}

You can also use java.util.zip.ZipInputStream instead, as seeing a JAR file is in the same format as a ZIP file, ZipInputStream will be able to handle the Jar file, in fact JarInputStream actually extends ZipInputStream.

an alternative is also instead of getNextJarEntry, to use getNextEntry