Determine the Java Class File Major & Minor Version

Question

Did anyone tried to look at the Major & Minor version of a specific java class file.
Our server is running in version 1.3. We are including a third party class file, I like to check before our production move, whether the file is compiled is <= Jdk1.3.
Thanks in Advance.

Answer 1

// 1) Download Jakarta BCEL
// 2) compile this class
import org.apache.bcel.classfile.*;
public class Main
     public static void main(String[] args) throws Exception
          printClassVersion("c:\\foo.jar", "com/foo/Bar.class");
     public static void printClassVersion(String jarfile, String classfile) throws Exception
          ClassParser cp = new ClassParser(jarfile, classfile);
          JavaClass clazz1 = cp.parse();
          System.out.println(jarfile);
          System.out.println("Major: " + clazz1.getMajor());
          System.out.println("Minor: " + clazz1.getMinor());
}