Make copy of an array

Question

I have an array a which is constantly being updated. Let\'s say a = [1,2,3,4,5]. I need to make an exact duplicate copy of a and call

Answer 1

You can also use Arrays.copyOfRange.

Example:

public static void main(String[] args) {
    int[] a = {1,2,3};
    int[] b = Arrays.copyOfRange(a, 0, a.length);
    a[0] = 5;
    System.out.println(Arrays.toString(a)); // [5,2,3]
    System.out.println(Arrays.toString(b)); // [1,2,3]
}

This method is similar to Arrays.copyOf, but it's more flexible. Both of them use System.arraycopy under the hood.

See:

• https://docs.oracle.com/javase/8/docs/api/java/util/Arrays.html
• https://docs.oracle.com/javase/tutorial/java/nutsandbolts/arrays.html
• http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/8u40-b25/java/util/Arrays.java?av=f