Java return byte array

Question

public static void main (){
    byte[] a = get();
    byte[] b = {1,2,3,4};

    System.arraycopy(a, 0, b, 2, 2);
    System.arraycopy(b, 0, a, 0, 2);
}

public static byte[] get(){
    byte c={5,6}; // byte c= new byte[2];...
    return c;
}

My question is: what the difference between returning byte c={5,6} and byte c=new byte[2]; c[0]=5;c[1]=6;?

Possible duplicate of [Declare array (Java)](http://stackoverflow.com/questions/1200621/declare-array-java) and btw `byte c={5,6};` wont work. It must be `byte[] c={5,6};` — ArcticLord, Feb 23 '16 at 11:51
Apart from the fact that the first is a static initializer, there is none. Why? — fge, Feb 23 '16 at 11:51
despite the fact that this wont compile, since `c` is declared to be a `byte` and not a `byte` array, there is none, both create a new array. — SomeJavaGuy, Feb 23 '16 at 11:52
There is no difference, the resulting bytecode will use the same instruction (newarray). — Jean-François Savard, Feb 23 '16 at 11:54
sorry guys, for I post it by my phone, so ... eh...sorry for my miss typing ;) — user4878054, Feb 23 '16 at 11:57
You can here find some information about the [shortcut syntax](https://docs.oracle.com/javase/tutorial/java/nutsandbolts/arrays.html). As @Jean-FrançoisSavard said they will be compiled to the same bytecode. — SubOptimal, Feb 23 '16 at 12:21

Yoav Gur · Answer 1 · 2016-02-23T12:33:11.617

0

c={5,6} initializes the array with an array of size 2, and values "5" and "6".
c=new byte[2] initializes the array with an array of size 2, and values 0 and 0.

edited Feb 23 '16 at 12:33

answered Feb 23 '16 at 11:54

Yoav Gur

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primitives can´t be `null` – SomeJavaGuy Feb 23 '16 at 11:57

Java return byte array

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