How do you get rid of null in a String in Java?

Question

I have this string "nullRobert Luongo 431-232-1233 Canada"

and I'd like to get rid of the null character. I don't know how it got there, but I would like to get rid of it.

Never look for bandaids. Fix things at their source. It will save you a lot of headache. — Achrome, Sep 29 '14 at 00:14
This has already been answered here :http://stackoverflow.com/questions/2523284/java-string-replace-and-the-nul-null-ascii-0-character — Sevman, Sep 29 '14 at 00:17

score 4 · Accepted Answer · answered Sep 29 '14 at 00:20

4

It's likely that you get it because you did something like this:

String s = null;
.
.
.
s+="Robert Luongo 431-232-1233 Canada"; //mind the +=

One way to correctly do it is by:

String s= "";

answered Sep 29 '14 at 00:20

adhg

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Oh, that's probably what I did. – IceKing Sep 29 '14 at 00:25

score 3 · Answer 2 · answered Sep 29 '14 at 00:19

3

You're concatenating a String that is null -- don't do that. Initialize the String at least with ""

So rather than

String myString;

When you do this and later do:

myString += "something";

you'll get `nullsomething

So instead assign an empty String to the String of interest when you declare it.

String myString = "";

answered Sep 29 '14 at 00:19

Hovercraft Full Of Eels

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That is just one out of many different reasons why the OP could end up with this String...!? – Jan Groth Sep 29 '14 at 00:22
@jangroth: true, but the most common that I've seen. – Hovercraft Full Of Eels Sep 29 '14 at 00:25
it is too much for me that someone questioned you @HovercraftFullOfEels – Kick Buttowski Sep 29 '14 at 02:54
@KickButtowski: sorry that makes no sense. jan groth's comments were spot on. – Hovercraft Full Of Eels Sep 29 '14 at 03:01
@HovercraftFullOfEels it does not matter if it makes sense or not, but I sitll cannot consume someone questioned you :) – Kick Buttowski Sep 29 '14 at 03:01

score 0 · Answer 3 · answered Sep 29 '14 at 00:22

Option 1: Recommended

I would suggest you to look into the issue from where the string is contains 'null' and fix it at the source rather than using hacks.

Option 2: Not recommended

But still if you want to replace the null from it then you can use the following. But it is not recommended as it can replace a proper word containing 'null' in it and make the string junk.

The following replaces the first instance of 'null' with empty String.

string.replace("null", "");

You can also replace all the instances of 'null' with empty String using replaceAll.

string.replaceAll("null", "");

score 0 · Answer 4 · answered Sep 29 '14 at 00:24

0

You can use this.

String stringWithoutNull = stringWithNull.replaceAll("null", "");

answered Sep 29 '14 at 00:24

How do you get rid of null in a String in Java?

4 Answers4