Java I/O How to - Create a Manifest for a JAR File

Question

We would like to know how to create a Manifest for a JAR File.

Answer

  /*from  w  ww  .j ava 2  s  .c  om*/


import java.io.ByteArrayInputStream;
import java.io.FileInputStream;
import java.io.InputStream;
import java.util.jar.Manifest;

public class Main {
  public static void main(String[] argv) throws Exception {
    // Create a manifest from a file
    InputStream fis = new FileInputStream("manifestfile");
    Manifest manifest = new Manifest(fis);

    // Construct a string version of a manifest
    StringBuffer sbuf = new StringBuffer();
    sbuf.append("Manifest-Version: 1.0\n");
    sbuf.append("\n");
    sbuf.append("Name: javax/swing/JScrollPane.class\n");
    sbuf.append("Java-Bean: True\n");

    // Convert the string to a input stream
    InputStream is = new ByteArrayInputStream(sbuf.toString().getBytes("UTF-8"));

    // Create the manifest
    manifest = new Manifest(is);
  }
}