Java™ Application Development on Linux - Dator

68Chapter 3An Experienced Programmer’s Introduction to JavaExample 3.9 A Java while statementwhile (greble != null){greble.glib();greble = treempl.morph();}Technically, the while statement consists of the expression and a singlestatement, but that single statement can be replaced by a set of statements enclosedin braces (you know, the characters { and }). We will always use braces,even if there is only one statement in our while loop. Experience has shownthat it’s a safer practice that leads to code that is easier to maintain. Just treatit as if the braces were required syntax, and you’ll never forget to add themwhen you add a second statement to a loop.The do-while loop. To put the terminating check at the bottom of theloop, use do-while as shown in Example 3.10. Notice the need for theterminating semicolon after the expression.Example 3.10 A Java do-while statementdo {greble.morph();xrof = treempl.glib();} while (xrof == null);Die-hard Pascal programmers should note that Java has no repeat-untilstatement. Sorry. Of course the logic of an until(condition) is equivalentto do-while(!condition).The for loop. The for loop in Java is very similar to C/C++. It consists ofthree parts (Example 3.11):• The initializing expression, done up front before the loop begins• The conditional expression for terminating the loop