java System.arraycopy 数组复制和合并

public class Test {
public static void main(String[] args)  {
Integer[] a = {1,2,3};
Integer[] b = {4,5,6};
Integer[] c = new Integer[a.length+b.length];
System.arraycopy(a, 0, c, 0, a.length);
System.arraycopy(b, 0, c, b.length, b.length);
for(Integer i : c){
System.out.println(i);
}
}
}