5Controlling the Flow of Your Program


  • How to determine if a certain condition is met
  • How to control what a Java program does and when it should do it
  • How to use loops in Java to repeat an action
  • How to determine which control structure to use


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Control structures allow a programmer to define how and when certain statements will be executed. In other words, if certain conditions are met, specified behaviors will result. Several structures exist in Java and other languages, such as loops and if-then statements, which allow this control to be implemented. This chapter begins by introducing (or re-introducing) some operators that will be used extensively in control structures. The operators, essentially, allow you to compare values. In order to make similar comparisons on different data types, some comparative methods will also be introduced. Once you can make these comparisons and assessments, you can start using them to make decisions. That is where the if-then statement comes in. In its simplest form, this structure can be read as follows: if some condition is true, then do something. Next, you will look at for and while loops, and some extensions of these, ...

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