How do I remove spaces in a String (sentence)

Question

I need to remove all spaces from it.

Eg: This is my code O/P : Thisismycode

This is my code so far.

import java.util.Scanner;
public class nospace{

public static void main(String args[]){

    Scanner s=new Scanner(System.in);

    System.out.println("Enter a String");
    String N=s.nextLine();
    N=N.trim();
    N=N+" ";
    int l=N.length();
    int a=0;
    for(int i=0;i<=l-1;i++){
        if(N.charAt(i)==32){
    System.out.println(N.substring(a,i+1));
    }
    a=i;

    }

}

}

All it does it print the last letters of each word. Any help is appreciated.

possible duplicate of [Java: remove all occurances of char from string](http://stackoverflow.com/questions/4576352/java-remove-all-occurances-of-char-from-string) — aruisdante, Mar 12 '14 at 19:25

Endrik · Answer 1 · 2014-03-12T19:27:14.077

5

you can try to us this piece of code

N.replaceAll("\\s+","")

This states that you replace all white spaces inside a string object with an empty string (""). The part "\\s+" is called a regex and in combination with replaceAll removes all whitespaces and non visible characters such as tab. Also notice that st.replaceAll("\\s","") produces the same result. The second regex is faster than the first one. But we increase the number consecutive spaces, first one performs better than the second one

edited Mar 12 '14 at 19:27

answered Mar 12 '14 at 19:21

Endrik

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The general doc for replaceAll is available [here](http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#replaceAll%28java.lang.String,%20java.lang.String%29) – aruisdante Mar 12 '14 at 19:24
2

A plain `replace(" ", "")` is enough and doesn't involve regex. – Marko Topolnik Mar 12 '14 at 19:28

score 2 · Answer 2 · answered Mar 12 '14 at 19:27

I would recommend using Java's string replaceAll function. You give it the regex that you're looking to replace, and what you want to replace it with:

string.replaceAll("\\s+", "");

So your code should look like this:

import java.util.Scanner;
public class nospace{

public static void main(String args[]){

    Scanner s=new Scanner(System.in);

    System.out.println("Enter a String");
    String input=s.nextLine();
    input = input.replaceAll("\\s+", "");
    System.out.println(input);

}

}

I changed your input variable from N to input - in Java you shouldn't use capital letters to start the name of a variable. Additionally, I removed some of the other lines you had, such as adding a space to the end of your input string, and creating the l and a variables.

score 1 · Answer 3 · answered May 30 '18 at 07:53

1

If you want to do something with Strings in Java, Commons Lang StringUtils is a great place to look.

String newString = StringUtils.deleteWhitespace(oldStr);

answered May 30 '18 at 07:53

Deb

2,922
1
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32

score 0 · Answer 4 · answered Jul 17 '16 at 18:17

Try this:

public class RemoveExtraspaces {
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        String str="   Hello and welcome !    let's start    coding    ";
        char prev;
        char current;
        String punc="?,.!";
        String result = "";
        for(int i=1;i<str.length();i++){
            current=str.charAt(i);
            prev=str.charAt(i-1);
            if(current==' ' && prev==' ' && punc.indexOf(current)<0){
                prev=current;
            }
            else if(punc.indexOf(current)>0){
                if(prev==' ')
                    result=result.substring(0,result.length()-1);
                    result=result+current;
            }
            else {
                result=result+current;
            }
        }
        System.out.println(result);

    }


}

This is to remove extra spaces. Others are trying to remove all spaces — He Zhang, Sep 09 '16 at 19:12

How do I remove spaces in a String (sentence)

4 Answers4