Thinking In Java
Thinking In Java
The definitive introduction to object-oriented programming in the language of the world wide web

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Chapter 3 - Controlling Execution

Control statements: if-else while do-while for return break true and false All conditional statements use truth or falsehood of a conditional expression to determine the execution path. Number can’t be used as boolean, alternative way: if (a!=0) if-else Two forms of using if: if(Boolean-expression) statement or if(Boolean-express) statement else statement Iteration Iteration statements (looping): while do-while for while while(Boolean-expression) statement do-while do statement while(Boolean-expression) for for(initialization; Boolean-expression; step) statement The comma operator Using the comma operator, you can define multiple variables within a for statement, but they must be of the same type.


Chapter 2 - Everything Is an Object

The Java language assumes that you want to do only object-oriented programming, so (almost) everything in Java is an object. You manipulate objects with references You treat everything as an object, using a single consistent syntax. Although you treat everything as an object, the identifier you manipulate is actually a “reference” to an object. For example: String s; You must create all the objects When you create a reference, you want to connect it with a new object.


Chapter 1 - Introduction to Objects

The progress of abstraction Five basic characteristics of object-oriented programming: Everything is an object. A program is a bunch of objects telling each other what to do by sending messages. Each object has its own memory made up of other objects. Every object has a type All objects of a particular type can receive the same messages. An object has an interface The interface determines what request you can make for a particular object.