Use the System.arraycopy Method to Copy Contents of Arrays

Use the System.arraycopy Method to Copy Contents of Arrays

When copying the contents of one array into another, use the System.arraycopy method instead of an iterative loop. For example, consider the following arrays:

 	int[] first = {1, 2, 3};	int[] second = {4, 5, 6};	int[] third = new int[first.length + second.length];

One possible way of copying the contents of the first two arrays into the third one is to use loops, such as:

 	for (int i = 0; i < first.length; i++)		third[i] = first[i];	for (int i = 0; i < second.length; i++)		third[first.length + i] = second[i];

However, a better way of accomplishing the same task is to use the System.arraycopy method as in the following example:

 	System.arraycopy(first, 0, third, 0, first.length);	System.arraycopy(second, 0, third, first.length, second.length); 

Besides accomplishing the same result with less code, this approach has the added advantage of being faster, since arraycopy is implemented as a native method, and will generally execute faster than equivalent code written in Java. This advantage can be particularly significant with large arrays or where many arrays are being copied.

See also  5 Tips for Choosing the Right Medical Software for Your Practice

About Our Editorial Process

At DevX, we’re dedicated to tech entrepreneurship. Our team closely follows industry shifts, new products, AI breakthroughs, technology trends, and funding announcements. Articles undergo thorough editing to ensure accuracy and clarity, reflecting DevX’s style and supporting entrepreneurs in the tech sphere.

See our full editorial policy.

About Our Journalist