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How to remove the last character from a string?

I want to remove the last character from a string. I've tried doing this:

public String method(String str) {
    if (str.charAt(str.length()-1)=='x'){
        str = str.replace(str.substring(str.length()-1), "");
        return str;
    } else{
        return str;
    }
}

Getting the length of the string - 1 and replacing the last letter with nothing (deleting it), but every time I run the program, it deletes middle letters that are the same as the last letter.

For example, the word is "admirer"; after I run the method, I get "admie." I want it to return the word admire.


T
Tot Zam

replace will replace all instances of a letter. All you need to do is use substring():

public String method(String str) {
    if (str != null && str.length() > 0 && str.charAt(str.length() - 1) == 'x') {
        str = str.substring(0, str.length() - 1);
    }
    return str;
}

I'd add null != str && at the beginning of the check.
you mean str != null &&!
@SSpoke it's the same thing, yours is just a little nicer to read :)
@Marko lol yes since it's the standard, feels odd when people make their own stuff up.
@AdamJensen In C you could accidentally write if (str = NULL) which will not only always evaluate to false (NULL == 0 == false) but will also assign a value to str which is most likely not what you wanted to do. You could not write if (NULL = str) however because NULL is not a variable and cannot be assigned to. So, it is a safer convention to put the NULL on the left. This isn't an issue in Java though.
D
Daniel De León

Why not just one liner?

public static String removeLastChar(String str) {
    return removeLastChars(str, 1);
}

public static String removeLastChars(String str, int chars) {
    return str.substring(0, str.length() - chars);
}

Full Code

public class Main {
    public static void main (String[] args) throws java.lang.Exception {
        String s1 = "Remove Last CharacterY";
        String s2 = "Remove Last Character2";
        System.out.println("After removing s1==" + removeLastChar(s1) + "==");
        System.out.println("After removing s2==" + removeLastChar(s2) + "==");
    }
    
    public static String removeLastChar(String str) {
        return removeLastChars(str, 1);
    }

    public static String removeLastChars(String str, int chars) {
        return str.substring(0, str.length() - chars);
    }
}

Demo


The check for null and empty string should be considered.. @BobBobBob version is better
@KDjava : above is valid with considering that valid string is passed. else I would have to add the try catch block also to check that string is correct...
i added check for null string before return str.substring(0,str.length()-1); as improvement
@FahimParkar: Because it may be possible that last character is not the character that we want to remove. But as per the question, your answer is correct
i
iddqd

Since we're on a subject, one can use regular expressions too

"aaabcd".replaceFirst(".$",""); //=> aaabc  

nice way, when you want/need to define exactly what you want to trim from the end of the string, not just X whatever chars
u
user3132194

The described problem and proposed solutions sometimes relate to removing separators. If this is your case, then have a look at Apache Commons StringUtils, it has a method called removeEnd which is very elegant.

Example:

StringUtils.removeEnd("string 1|string 2|string 3|", "|");

Would result in: "string 1|string 2|string 3"


Here's the JAR for the aforementioned StringUtils: commons.apache.org/proper/commons-lang/download_lang.cgi
B
BobBobBob
public String removeLastChar(String s) {
    if (s == null || s.length() == 0) {
        return s;
    }
    return s.substring(0, s.length()-1);
}

What if the last character is a high/low surrogate pair?
@RobertAllanHenniganLeahy I posted an answer that handles that scenario.
u
user3132194

Don't try to reinvent the wheel, while others have already written libraries to perform string manipulation: org.apache.commons.lang3.StringUtils.chop()


If you want to remove the last character ONLY - this is the best answer!
No it isn't, because "use Java" is a terrible answer to a Kotlin question.
@MikkelLøkke I don't know, but this question is not a Kotlin question in any case??
J
Jeeva

In Kotlin you can used dropLast() method of the string class. It will drop the given number from string, return a new string

var string1 = "Some Text"
string1 = string1.dropLast(1)

B
Bhavin Nattar

Use this:

 if(string.endsWith("x")) {

    string= string.substring(0, string.length() - 1);
 }

C
Community
if (str.endsWith("x")) {
  return str.substring(0, str.length() - 1);
}
return str;

For example, the word is "admirer"; after I run the method, I get "admie." I want it to return the word admire.

In case you're trying to stem English words

Stemming is the process for reducing inflected (or sometimes derived) words to their stem, base or root form—generally a written word form. ... A stemmer for English, for example, should identify the string "cats" (and possibly "catlike", "catty" etc.) as based on the root "cat", and "stemmer", "stemming", "stemmed" as based on "stem". A stemming algorithm reduces the words "fishing", "fished", "fish", and "fisher" to the root word, "fish".

Difference between Lucene stemmers: EnglishStemmer, PorterStemmer, LovinsStemmer outlines some Java options.


K
Kasturi

As far as the readability is concerned, I find this to be the most concise

StringUtils.substring("string", 0, -1);

The negative indexes can be used in Apache's StringUtils utility. All negative numbers are treated from offset from the end of the string.


I wouldn't say this is the best answer - for simplicity use org.apache.commons.lang.StringUtils.chop() method. Yet, the trick with -1 is really nice and looking at the other answers is not really used / well known.
D
Donoso
 string = string.substring(0, (string.length() - 1));

I'm using this in my code, it's easy and simple. it only works while the String is > 0. I have it connected to a button and inside the following if statement

if (string.length() > 0) {
    string = string.substring(0, (string.length() - 1));
}

G
Ganesa Vijayakumar
public String removeLastChar(String s) {
    if (!Util.isEmpty(s)) {
        s = s.substring(0, s.length()-1);
    }
    return s;
}

A
Arkadiusz Cieśliński

removes last occurence of the 'xxx':

    System.out.println("aaa xxx aaa xxx ".replaceAll("xxx([^xxx]*)$", "$1"));

removes last occurrence of the 'xxx' if it is last:

    System.out.println("aaa xxx aaa  ".replaceAll("xxx\\s*$", ""));

you can replace the 'xxx' on what you want but watch out on special chars


B
Bachan Joseph
 // creating StringBuilder
 StringBuilder builder = new StringBuilder(requestString);
 // removing last character from String
 builder.deleteCharAt(requestString.length() - 1);

t
tstempko

How can a simple task be made complicated. My solution is:

public String removeLastChar(String s) {
    return s[0..-1]
}

or

public String removeLastChar(String s) {
    if (s.length() > 0) {
        return s[0..-1]
    }
    return s
}

Is s[0..-1] java?
bruh.. this is not java
a
aeocom

Look to StringBuilder Class :

    StringBuilder sb=new StringBuilder("toto,");
    System.out.println(sb.deleteCharAt(sb.length()-1));//display "toto"

i
intcreator
// Remove n last characters  
// System.out.println(removeLast("Hello!!!333",3));

public String removeLast(String mes, int n) {
    return mes != null && !mes.isEmpty() && mes.length()>n
         ? mes.substring(0, mes.length()-n): mes;
}

// Leave substring before character/string  
// System.out.println(leaveBeforeChar("Hello!!!123", "1"));

public String leaveBeforeChar(String mes, String last) {
    return mes != null && !mes.isEmpty() && mes.lastIndexOf(last)!=-1
         ? mes.substring(0, mes.lastIndexOf(last)): mes;
}

N
Nick Louloudakis

A one-liner answer (just a funny alternative - do not try this at home, and great answers already given):

public String removeLastChar(String s){return (s != null && s.length() != 0) ? s.substring(0, s.length() - 1): s;}

M
MC Emperor

Most answers here forgot about surrogate pairs.

For instance, the character 𝕫 (codepoint U+1D56B) does not fit into a single char, so in order to be represented, it must form a surrogate pair of two chars.

If one simply applies the currently accepted answer (using str.substring(0, str.length() - 1), one splices the surrogate pair, leading to unexpected results.

One should also include a check whether the last character is a surrogate pair:

public static String removeLastChar(String str) {
    Objects.requireNonNull(str, "The string should not be null");
    if (str.isEmpty()) {
        return str;
    }

    char lastChar = str.charAt(str.length() - 1);
    int cut = Character.isSurrogate(lastChar) ? 2 : 1;
    return str.substring(0, str.length() - cut);
}

On a corner case : can this ever throw IndexOutOfBoundsException ? (e.g. is it possible that Character.isSurrogate returns true when there is actually no char before it, making str.length()-cut negative).
Yes, that's possible. It's an invalid string anyway, but still – it's possible, yes. One should then replace 2 by Math.min(2, str.length()).
N
Nadhu

Java 8

import java.util.Optional;

public class Test
{
  public static void main(String[] args) throws InterruptedException
  {
    System.out.println(removeLastChar("test-abc"));
  }

  public static String removeLastChar(String s) {
    return Optional.ofNullable(s)
      .filter(str -> str.length() != 0)
      .map(str -> str.substring(0, str.length() - 1))
      .orElse(s);
    }
}

Output : test-ab


C
C Williams
public String removeLastCharacter(String str){
       String result = null;
        if ((str != null) && (str.length() > 0)) {
          return str.substring(0, str.length() - 1);
        }
        else{
            return "";
        }

}

V
Vasanthakumar Jagannathan

if we want to remove file extension of the given file,

** Sample code

 public static String removeNCharactersFromLast(String str,int n){
    if (str != null && (str.length() > 0)) {
        return str.substring(0, str.length() - n);
    }

    return "";

}

M
MoadKey

if you have special character like ; in json just use String.replace(";", "") otherwise you must rewrite all character in string minus the last.


T
Tilak Maddy

Why not use the escape sequence ... !

System.out.println(str + '\b');

Life is much easier now . XD ! ~ A readable one-liner


Isn't this Java. LMAO
Special behaviour of '\b' is interpreted by string reader, text terminals etc.. otherwise it's just another ASCII character representation. stackoverflow.com/a/11891895/4589003
C
CodeF0x

How to make the char in the recursion at the end:

public static String  removeChar(String word, char charToRemove)
    {
        String char_toremove=Character.toString(charToRemove);
        for(int i = 0; i < word.length(); i++)
        {
            if(word.charAt(i) == charToRemove)
            {
                String newWord = word.substring(0, i) + word.substring(i + 1);
                return removeChar(newWord,charToRemove);
            }
        }
        System.out.println(word);
        return word;
    }

for exemple:

removeChar ("hello world, let's go!",'l') → "heo word, et's go!llll"
removeChar("you should not go",'o') → "yu shuld nt goooo"

P
Patrick Parker

Here's an answer that works with codepoints outside of the Basic Multilingual Plane (Java 8+).

Using streams:

public String method(String str) {
    return str.codePoints()
            .limit(str.codePoints().count() - 1)
            .mapToObj(i->new String(Character.toChars(i)))
            .collect(Collectors.joining());
}

More efficient maybe:

public String method(String str) {
    return str.isEmpty()? "": str.substring(0, str.length() - Character.charCount(str.codePointBefore(str.length())));
}

S
Syed Salman Hassan

just replace the condition of "if" like this:

if(a.substring(a.length()-1).equals("x"))'

this will do the trick for you.


D
Dharman

Suppose total length of my string=24 I want to cut last character after position 14 to end, mean I want starting 14 to be there. So I apply following solution.

String date = "2019-07-31T22:00:00.000Z";
String result = date.substring(0, date.length() - 14);

U
Unmitigated

I had to write code for a similar problem. One way that I was able to solve it used a recursive method of coding.

static String removeChar(String word, char charToRemove)
{
    for(int i = 0; i < word.lenght(); i++)
    {
        if(word.charAt(i) == charToRemove)
        {
            String newWord = word.substring(0, i) + word.substring(i + 1);
            return removeChar(newWord, charToRemove);
        }
    }

    return word;
}

Most of the code I've seen on this topic doesn't use recursion so hopefully I can help you or someone who has the same problem.


R
RoboC

Easy Peasy:

StringBuilder sb= new StringBuilder();
for(Entry<String,String> entry : map.entrySet()) {
        sb.append(entry.getKey() + "_" + entry.getValue() + "|");
}
String requiredString = sb.substring(0, sb.length() - 1);