java - removing semi colon from a string if the string ends with it

Question

I have a requirement in which I need to remove the semicolon if it is present at the end of the String(only at the end). I have tried the following code. But still it is not getting replaced. Can anyone please tell what I need to change in the following code in the line number
(I referred the code from here How do I delete specific characters from a particular String in Java?)

public static void main(String[] args) {
    String text = "wherabouts;";
    System.out.println("SSS "+text.substring(text.length()-1));
    if(text.substring(text.length()-1) == ";"){
        text.replaceAll(";", "");
    }
    System.out.println("TEXT : "+text);
}

The character isn't replaced as clearly stated in his original post. — dan, Oct 09 '12 at 18:32

Rohit Jain · Accepted Answer · 2013-09-27T09:41:34.693

text.replaceAll(";", "");

Since Strings in Java are immutable, so replaceALl() method doesn't do the in-place replacement, rather it returns a new modified string. So, you need to store the return value in some other string. Also, to match the semi-colon at the end, you need to use $ quantifier after ;

text = text.replaceAll(";$", "");

$ denotes the end of the string since you want to replace the last semi-colon..

If you don't use $, it will replace all the ; from your strings..

Or, for your job, you can simply use this, if you want to remove the last ;:

    if (text.endsWith(";")) {
        text = text.substring(0, text.length() - 1);
        System.out.println(text);
    }

UPDATE: And, if there are more semi-colons at the end:

text = text.replaceAll(";+$", "");

jahroy · Answer 2 · 2012-10-09T21:24:58.453

18

String modifiedText = text.replaceAll(";$", "");

OR

text = text.replaceAll(";$", "");

OR

if (text.endsWith(";")) {
    text = text.substring(0, text.length() - 1);
}

NOTE:

Strings are immutable. That means you can't change them.

Therefore you have to either re-assign text or set it to a new variable.

edited Oct 09 '12 at 21:24

answered Oct 09 '12 at 18:32

jahroy

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what s the $ sign at the end for? regex? endswith? – DarthVader Oct 09 '12 at 18:39
1

Correct, the `$` symbol represents _the end of input_ in a regex. This typically helps to match a pattern that appears at the end of a line or the end of a string. This causes `text.replaceAll(";$", "")` to replace only a semi-colon that appears as the last character. – jahroy Oct 09 '12 at 18:40
Note that as @RohitJain has pointed out, if you want to deal with the possibility of multiple semi-colons at the end of the line, you can add a `+` symbol: `text.replaceAll(";+$", "");` – jahroy Oct 09 '12 at 19:04

score 4 · Answer 3 · answered Oct 09 '12 at 18:31

4

text = text.replaceAll(";", "");

Here's a little extra reading for you http://javarevisited.blogspot.com/2010/10/why-string-is-immutable-in-java.html

answered Oct 09 '12 at 18:31

Louis Ricci

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score 3 · Answer 4 · answered Oct 09 '12 at 18:32

3

You should not forget that String is immutable. So, whenever you want to modify it, you have to assign the result to a variable.

A possible solution to what you need:

if (text.endsWith(";") {
  text = text.substring(0, text.length() - 1);
}

answered Oct 09 '12 at 18:32

Dan D.

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I didn't downvote, but I believe the OP only wants to replace semi-colons at the end of the string. – jahroy Oct 09 '12 at 18:34
Awesome. Thanks for not down-voting. – Dan D. Oct 09 '12 at 18:40

score 2 · Answer 5 · answered Oct 09 '12 at 18:32

2

Strings in java are immutable, so replaceAll returns a new string.

Do

 text = text.replaceAll(";", "");

answered Oct 09 '12 at 18:32

Denys Séguret

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asteri · Answer 6 · 2012-10-09T18:42:46.777

2

Use .equals() instead of == if you're going to use substring() rather than charAt():

if(text.substring(text.length()-1).equals(";"))

Also, reassign your text variable:

text = text.replaceAll(";", "");

edited Oct 09 '12 at 18:42

answered Oct 09 '12 at 18:32

asteri

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You need a paren around the string after `equals`. – jahroy Oct 09 '12 at 18:42
Thanks for the catch. :) Not that the OP needs more examples or answers at this point. Haha – asteri Oct 09 '12 at 18:43
Can you please tell - what if there are 2 semi colons at the end of string? – user1732653 Oct 09 '12 at 18:48
All of them will be effectively erased from the String, since you are using `replaceAll()`. – asteri Oct 09 '12 at 18:49

score 2 · Answer 7 · answered Oct 09 '12 at 18:34

2

if (text.endsWith(";")){
    text = text.substring(0,text.length()-1);
}

answered Oct 09 '12 at 18:34

ewok

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score 2 · Answer 8 · answered Oct 09 '12 at 18:34

2

You are using the wrong version of String.substring, You could use:

text.substring(0, text.length() - 1)

answered Oct 09 '12 at 18:34

Reimeus

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score 2 · Answer 9 · answered Oct 09 '12 at 18:36

2

String is immutable so new String will be created after replace.

String newString = text.replace(";", "");

or

String newString = text.replaceAll(";$", "");

answered Oct 09 '12 at 18:36

Subhrajyoti Majumder

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score 1 · Answer 10 · edited May 23 '17 at 11:54

1

There are multiple problems in the code you have provided.

Use equals to compare objects.

if(text.substring(text.length()-1).equals(";"))

If you want to replace only the last character, you dont need replaceAll.

So do either

if(text.substring(text.length()-1).equals(";")) {
      text = text.substring(0, text.length()-1);
    }

or

text = text.replaceAll(";", "");

edited May 23 '17 at 11:54

Community

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answered Oct 09 '12 at 18:44

Nivas

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score 1 · Answer 11 · answered Oct 09 '12 at 18:50

public static void main(String[] args) {
    String text_original = "wherabouts;";
    char[] c = text_original.toCharArray();

    System.out.println("TEXT original: "+ text_original);

    String text_new = c[text_original.length()-1] == ';' ? text_original.substring(0,text_original.length()-2) : text_original;

    System.out.println("TEXT new: "+text_new);
}

score 1 · Answer 12 · answered Oct 09 '12 at 18:55

Solution for only one semi-colon

// Don't use regular expressions if you don't need to.
if (text.endsWith(";")) {
    text = text.substring(0, text.length() - 1);
}

Slower solution for possibly more than one semi-colon

text.replaceAll(";+$", "");

Additionally, here are some other problems with the code you originally posted, for reference.

if(text.substring(text.length()-1) == ";"){

You can't compare strings with ==. Instead, you have to compare them with .equals(). This would be correctly written like this ...ength()-1).equals(";").

text.replaceAll(";", "");

This replaces all semicolons it finds. This means that if your string was some;thing;, it would turn it into something, but you want to only remove the last semicolon, like this: some;thing. To do this correctly, you need to look for the end of the string, using the special $ character like this:

text.replaceAll(";$", "");

java - removing semi colon from a string if the string ends with it

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