Retrieves the manifest from a JAR file and writes the manifest contents to a file. : JarFile « File « Java Tutorial

1. Java Tutorial
2. File
3. JarFile

import java.io.FileOutputStream;
import java.io.OutputStream;
import java.util.jar.JarFile;
import java.util.jar.Manifest;

public class Main {
  public static void main(String[] argv) throws Exception {
    JarFile jarfile = new JarFile("filename.jar");

    Manifest manifest = jarfile.getManifest();

    OutputStream fos = new FileOutputStream("manifest");
    jarfile.getManifest().write(fos);
    fos.close();
  }
}