A Java int array example

Java array FAQ: How do you create an array of Java int values (i.e., a Java "int array")?

Answer: There are several ways to define an int array in Java; let's take a look at a few examples.

Java int array - Example 1

If you know the desired size of your array, an you'll be adding elements to your array some time later in your code, you can define a Java int array using this syntax:

// (1) create a java int array
int[] intArray = new int[3];

// (2) some time later ... assign elements to the array
intArray[0] = 1;
intArray[1] = 2;
intArray[2] = 3;

// (3) print our java int array
for (int i=0; i<intArray.length; i++)
{
  System.out.println(intArray[i]);
}

Java int array - Example 2

Depending on your needs, you can also create your int array using this syntax:

// (1) define your java int array
int[] intArray = new int[] {4,5,6,7,8};

// (2) print the java int array
for (int i=0; i<intArray.length; i++)
{
  System.out.println(intArray[i]);
}

A complete Java int array example

Sometimes it helps to see source code used in a complete Java program, so the Java class/program below demonstrates the different Java int array examples.

The method named intArrayExample shows our first example. Then, to demonstrate the similiarity between an int array and a String array, the method named stringArrayExample shows how a Java String array is typically created and populated. Finally, the method named intArrayExample2 shows our second int array example (as shown above).

Here's the source code for my sample Java class:

/**
 * Demonstrates several Java array examples, including a
 * Java int array, and a Java String array.
 * Created by Alvin Alexander, http://alvinalexander.com.
 */
public class JavaIntArrayExample
{

  public static void main(String[] args)
  {
    new JavaArrayExample();
  }

  public JavaArrayExample()
  {
    intArrayExample();
    stringArrayExample();
    intArrayExample2();
  }

  /**
   * Create an int array, then populate the array, 
   * and finally print each element in the int array.
   */
  private void intArrayExample()
  {
    int[] intArray = new int[3];
    intArray[0] = 1;
    intArray[1] = 2;
    intArray[2] = 3;
    System.out.println("intArray output");
    for (int i=0; i<intArray.length; i++)
    {
      System.out.println(intArray[i]);
    }
  }

  /**
   * Create a String array, then populate the array, 
   * and finally print each element in the int array.
   */
  private void stringArrayExample()
  {
    String[] stringArray = new String[3];
    stringArray[0] = "a";
    stringArray[1] = "b";
    stringArray[2] = "c";
    System.out.println("stringArray output");
    for (int i=0; i<stringArray.length; i++)
    {
      System.out.println(stringArray[i]);
    }
  }

  /**
   * Create a Java int array and populate it in one step.
   * Then get the array length and print each element in the array.
   */
  private void intArrayExample2()
  {
    int[] intArray = new int[] {4,5,6,7,8};
    System.out.println("intArray output (version 2)");
    for (int i=0; i<intArray.length; i++)
    {
      System.out.println(intArray[i]);
    }
  }

}

Feel free to use these "int array" examples for your own tests, or in your own code. Also, if you have other Java array examples you'd like to share, or any questions or comments, just use the comment form below.

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