How do I reverse an int array in Java?

java arrays idioms idiomatic
MichaelScott picture MichaelScott · Jan 26, 2010 · Viewed 553.7k times · Source

I am trying to reverse an int array in Java.

This method does not reverse the array. 

for(int i = 0; i < validData.length; i++)
{
    int temp = validData[i];
    validData[i] = validData[validData.length - i - 1];
    validData[validData.length - i - 1] = temp;
}

What is wrong with it?

Answer

Manur picture Manur · Jan 26, 2010

With Commons.Lang, you could simply use 

ArrayUtils.reverse(int[] array)

Most of the time, it's quicker and more bug-safe to stick with easily available libraries already unit-tested and user-tested when they take care of your problem.

Related questions

How do I declare and initialize an array in Java?

How do I declare and initialize an array in Java?

Read More
What's the simplest way to print a Java array?

In Java, arrays don't override toString(), so if you try to print one directly, you get the className + '@' + the hex of the hashCode of the array, as defined by Object.toString(): int[] intArray = new int[] {1, 2, 3, 4, 5}; System.out.println(…

Read More
How do I determine whether an array contains a particular value in Java?

I have a String[] with values like so: public static final String[] VALUES = new String[] {"AB","BC","CD","AE"}; Given String s, is there a good way of testing whether VALUES contains s?

Read More