String constructor to handle byte array producing weird result

Question

I am using implicit String constructor that handle byte array..but it results weird. Do I have to do something more for proper output..? Any help will be appreciated. Here is my code..

    byte[] arr = { 23, 34, 20, 65, 88, 95 };

    String s1 = new String(arr);
    System.out.println("First: "+s1);

    String s2 = new String(arr, 1, 3);
    System.out.println("Second: "+s2);

it prints:

First: ?"?AX_

Second: ?AX

What is your expected output? 23 and 20 aren't printable characters, 34 is `"`, 65 is `A`, 88 is `X`, and 95 is `_`. — rgettman, May 16 '14 at 19:13
@rgettman:Yes you are right, I just tried it Starting with 65 as my books example did and it prints well..but how is that happening — Hello World, May 16 '14 at 19:16
Protip: get in the habit of explicitly *specifying* the encoding.. — user2864740, May 16 '14 at 19:22

score 2 · Accepted Answer · answered May 16 '14 at 19:27

The String() constructor you are using is interpreting the bytes in the array according to the default character set for your Java environment. That can differ.

If you have a specific character encoding that you want to use, like "US-ASCII" or "UTF-8", then you should specify the character set using a different constructor, such as: String(byte[] bytes, String charsetName).

score 1 · Answer 2 · answered May 16 '14 at 19:17

1

This is correct. Those are the characters for the codes that you provided. If you change your byte array to this, you'll see characters a-f:

byte[] arr = { 97, 98, 99, 100, 101, 102 };

answered May 16 '14 at 19:17

Edwin Torres

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String constructor to handle byte array producing weird result

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