在运行时获取jar版本

import javax.mail.internet.InternetAddress;public final class ReadVersion {  public static void main(String... aArgs){    ReadVersion readVersion = new ReadVersion();    readVersion.readVersionInfoInManifest();  }  public void readVersionInfoInManifest(){    InternetAddress object = new InternetAddress();    Package objPackage = object.getClass().getPackage();    //examine the package object     String name = objPackage.getSpecificationTitle();    String version = objPackage.getSpecificationVersion();    //some jars may use 'Implementation Version' entries in the manifest instead    System.out.println("Package name: " + name);    System.out.println("Package version: " + version);  }}