In this quick tutorial on how the Java HashMap works internally, you'll learn the following aspects: The basic syntax of the Java HashMap. How keys, values, hash codes and node references interact.

Hello, it seems I have similar issue to: #348 (comment), but on addItem(). I get this error: java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.String.hashCode()' on a ...