An objectâs behavior uses an objectâs unique state. Now weâll look at how state and behavior are related. We know that objects have state and behavior, represented by instance variables and methods. State affects behavior, behavior affects state. ÂLife on the garbage-collectible heapâ ÂAn object reference is just another variable valueâ ÂâIâd like a double mocha, no, make it an int.ââ And weâll finally see what life is truly like on the garbage-collectible heap. What if you have a PetOwner object with a Dog instance variable? Or a Car with an Engine? In this chapter weâll unwrap the mysteries of Java types and look at what you can declare as a variable, what you can put in a variable, and what you can do with a variable. Thereâs gotta be more to life than integers, Strings, and arrays. Variables come in two flavors: primitive and reference. Weâll look at how objects can improve your life. Weâll look at the difference between a class and an object. Weâll look at what makes object-oriented (OO) development in Java so much fun. So now weâve got to leave that procedural world behind and start making some objects of our own. In ChapterÂ 1, we put all of our code in the main() method. ÂCoding a serious business applicationâ Weâre talking syntax, loops, branching, and what makes Java so cool.

Weâll take a quick dip and write some code, compile it, and run it. From its humble release to the public as the (wimpy) version 1.02, Java seduced programmers with its friendly syntax, object-oriented features, memory management, and best of allâthe promise of portability. ÂLast-minute things you need to know:â ÂHereâs what YOU can do to bend your brain into submissionâ ÂMetacognition: thinking about thinkingâ Your brainâs thinking, âBetter leave room for more important things, like which wild animals to avoid and whether naked snowboarding is a bad idea.â So how do you trick your brain into thinking that your life depends on knowing Java? Here you are trying to learn something, while here your brain is doing you a favor by making sure the learning doesnât stick.

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