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System.arraycopy() vs. Arrays.copyOf() in Java

source: https://www.programcreek.com/2015/03/system-arraycopy-vs-arrays-copyof-in-java/ System.arraycopy() vs. Arrays.copyOf() in Java   If we want to copy an array, we can use either  System.arraycopy()  or  Arrays.copyOf() . In this post, I use a simple example to demonstrate the difference between the two. 1. Simple Code Examples System.arraycopy() int [ ] arr = { 1 , 2 , 3 , 4 , 5 } ;   int [ ] copied = new int [ 10 ] ; System . arraycopy ( arr, 0 , copied, 1 , 5 ) ; //5 is the length to copy   System . out . println ( Arrays . toString ( copied ) ) ; Output: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0] [0, 1, 2, 3, 4, 5, 0, 0, 0, 0] Arrays.copyOf() int [ ] copied = Arrays . copyOf ( arr, 10 ) ; //10 the the length of the new array System . out . println ( Arrays . toString ( copied ) ) ;   copied = Arrays . copyOf ( arr, 3 ) ; System . out . println ( Arrays . toString ( copied ) ) ; Output: [1, 2, 3, 4, 5, 0, 0, 0, 0, 0] [1, 2, 3] 2. The Major