Programming

The Java Virtual Machines manages memory. PermGen is part of the non-heap memory. From Java 8, PermGen was replaced by a new memory area called MetaSpace. Lewis explains the difference, and reminds developers to monitor memory usage.

Lewis shares some tips for Java programmers. These are reminders that he often repeats on every course. They are simple, obvious, and yet still sometimes forgotten. These apply to almost every programmer, so read on even if you don’t code in Java.

Java programmers need to decide which version of Java to use. They also need to decide which Java JDK to use. Lewis looks at some options.

A quick look at off-by-one errors and fence-post errors.

Ever wondered why Java arrays start from zero? Lewis explains

Shiny object syndrome is when we are distracted by anything new. Programmers like the idea of working on a new system, but there are many advantages to maintenance programming.

Sometimes you need to write a rich client graphical user interface in Java. Lewis looks at the standard JSE toolkits: AWT, Swing and JavaFX.

Sealed classes in Java are a way to control inheritance. This is a new feature in Java 17 and provides a cleaner approach than using access modifiers.

There are good reasons to upgrade from Java 8 to Java 17. Big companies don’t upgrade Java versions easily or quickly. Lewis compares the two versions to explain some of the advantages.