Learn how to use synchronous and asynchronous callbacks in Java—including callbacks with lambda expressions, CompletableFuture, and more.

Exception in thread "main" java.lang.AssertionError: x < 0 at AssertDemo.main(AssertDemo.java:6) For either example, running AssertDemo without the -ea (enable assertions) option results in no output.

For loops in Java are extremely powerful and lend themselves to many different coding applications. In this post, we will explain how to use them, and look at more advanced concepts such as labelling.