How to Write for-each Loops in Java

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In Brief...

The for-each loop was introduced in Java 5. Actually, the loop is a for loop with a : placed between a variable and a data structure such as an array. Each item of the data structure is stored in the variable per loop iteration. The loop terminates when the final item has been processed. To understand how to write for-each loops in Java, follow these four steps.

Instructions

  1. Open your text editor and type in the following Java statements:
    Java Source for for-each Loop
    The program creates and initializes an array of names. Next, the program uses a for-each loop to display each array element. Notice that the for-each loop stores each item of the names array in the name variable for each iteration of the loop.

  2. Save your file as WriteForEachLoops.java.

  3. Open a command prompt and navigate to the directory containing your Java program. Then type in the command to compile the source and hit Enter.
    Compile Source for for-each Program

  4. Now test your program. Type in the command to run the Java runtime launcher and then hit Enter. Notice the output of the program verifies that each array has been successfully processed by the for-each loop.
    Run for-each Program

Author: Stephen Withrow

Stephen has over 30 years' experience in training, development, and consulting in a variety of technology areas including Java, C, C++, XML, JavaScript, AJAX, Tomcat, JBoss, Oracle, and DB2. His background includes design and implementation of business solutions on client/server, Web, and enterprise platforms. Stephen is a published writer in both technical and non-technical endeavors. Stephen received an undergraduate degree in Computer Science and Physics from Florida State University.

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