View source for Java 8 Lambda Expressions

= Introduction =

TBD.

= Examples =

== Parameterless Void Method ==

Consider interface <code>Runnable</code>, which requires you to supply a <code>void run()</code> method in an implementation:

 public interface Runnable {
     void run();
 }

This is a common way of starting <code>Thread</code>s:

 public void startThread() {
     Runnable r = new Runnable() {
         public void run() {
             new JobRunner().doJob();
         }
     };
     Thread t = new Thread(r);
     t.start();
 }

Instead of going the long way, an anonymous inner class can be used in constructor parameter:

 public void startThread() {
     Thread t = new Thread(new Runnable() {
         public void run() {
             new JobRunner().doJob();
         }
     });
     t.start();
 }

One can now use a lambda expression to reduce the amount of boilerplate:

 public class MyCode {
     // ...
     public void startThread() {
         Runnable r = () -> { new JobRunner().doJob(); };
         Thread t = new Thread(r);
         t.start();
     }
     // ...
 }

Or even?

 public class MyCode {
     // ...
     public void startThread() {
         Thread t = new Thread(() -> { new JobRunner().doJob(); });
         t.start();
     }
     // ...
 }