import java.util.Properties;
import javax.mail.*;
....
....
....

 try{
     Properties props=new Properties();
    //Properties props = (Properties)System.getProperties().clone();
    props.put("mail.smtp.host", "whatever");
    // set as properties as needed
     
    javax.mail.Session session = javax.mail.Session.getDefaultInstance(props, null);
     
 //Properties props = new Properties(); 
 //Session session = Session.getDefaultInstance(props, null);
 Store store = session.getStore("pop3");
 store.connect(aHost, aUserName, aPassword);
 Folder folder = store.getFolder("INBOX"); 
 folder.open(Folder.READ_ONLY);
 Message message[] = folder.getMessages();
 for (int i = 0, n = message.length; i < n; i++) {
    System.out.println(i + ": " + message[i].getFrom()[0] + "\t" + message[i].getSubject());
 }
 folder.close(false);
 store.close();
 }
 catch(Exception e){
 System.err.println(e);
 e.printStackTrace();
 }

Exception in thread "main" java.lang.ClassFormatError: Absent Code attribute in method that is not native or abstract in class file javax/mail/Session
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:621)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
	at java.net.URLClassLoader.access$000(URLClassLoader.java:56)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
	at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
	at mymail.MyMail.main(MyMail.java:38)
Java Result: 1