Here you can find the source of concatIntArrays(final int[] l1, final int[] l2)
public static int[] concatIntArrays(final int[] l1, final int[] l2)
//package com.java2s; //License from project: Open Source License import java.util.Arrays; public class Main { public static int[] concatIntArrays(final int[] l1, final int[] l2) { if (l1 == null) return l2; if (l2 == null) return l1; final int[] result = Arrays.copyOf(l1, l1.length + l2.length); System.arraycopy(l2, 0, result, l1.length, l2.length); return result; }/*w w w.j a v a 2 s .c om*/ }