How to do a case-insensitive string replacement

Question

Hi friends I'm creating an app.
I want to find a particular word in an ArrayList and I have to replace
it with another word. I used the code below. It works case sensitive,
but I'd like to get it working case insensitive.

   FillintheBlank.class: 

          public class FillintheBlank extends Activity {
        static ArrayList<String> multiword=new ArrayList<String>();

 static ArrayList<String> multimeaning=new ArrayList<String>();


public void setNoTitle() {
    requestWindowFeature(Window.FEATURE_NO_TITLE);
} 
 float screenHeight,screenWidth,screendensity;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
     setNoTitle();
     getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
     DisplayMetrics displaymetrics = new DisplayMetrics();
     getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
     screenHeight = displaymetrics.heightPixels;
     screenWidth = displaymetrics.widthPixels;
     screendensity = displaymetrics.densityDpi;
    setContentView(R.layout.fillinblanknew);

             multiword.add("radha");
             multiword.add("RAdHA");
              multiword.add("latha");
                multiword.add("mammu");

              s.o.p(""+multiword);
            // output:radha,RADHA,latha,mamu

          multimeaning.add(multiword.getString().replace(radha,"sai"));
        s.o.p(""+multimeaning);
     // output: sai,RADHA,latha,mamu

 }
  }

For example: I need to replace 'radha' with 'sai' no matter what the case of the letters in 'radha' are.

http://jelaniharris.com/2009/case-insensitive-replaceall-in-java/ — MysticMagicϡ, Mar 25 '13 at 11:05
And another example on StackOverflow: http://stackoverflow.com/questions/5054995/how-to-replace-case-insensitive-literal-substrings-in-java — TimothyP, Mar 25 '13 at 11:11
Is this your actual working code? How are you doing a getString() on an ArrayList? — Alex Florescu, Mar 25 '13 at 11:21

Alex Florescu · Accepted Answer · 2013-03-25T11:24:10.157

12

Could use a regular expression. Just add (?i) before your string to ignore case.

So for example:

multiword.getString().replaceAll ( "(?i)radha", "sai");

edited Mar 25 '13 at 11:24

answered Mar 25 '13 at 11:03

Alex Florescu

5,096
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2

You're right, I don't think replace takes a regex, only replaceAll and replaceFirst – Alex Florescu Mar 25 '13 at 11:24

score 1 · Answer 2 · edited May 18 '17 at 11:21

1

You can "(?i)" pattern in front of a string to ignore the case.

public class StringReplace {

    public static void main(String[] args) {
        System.out.println(replaceString("This is a FISH", "IS"));
    }

    public static String replaceString(String first, String second) {
          return first.replaceAll("(?i)"+ second, "");
    }
}

The code above will return "Th a FH".

edited May 18 '17 at 11:21

Muhammed Refaat

8,914
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answered May 10 '17 at 22:17

rslj

330
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Naor Bar · Answer 3 · 2018-02-18T07:54:06.270

Use StringUtils by apache commons lang3 - v3.5 or later (so you don't have to worry about regular expression parsing):

StringUtils.replaceIgnoreCase(text, searchString, replacement);

or:

StringUtils.replaceOnceIgnoreCase(text, searchString, replacement);

If you use maven, add this dependency (I'm using version 3.6):

<!-- https://mvnrepository.com/artifact/org.apache.commons/commons-lang3 -->
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
    <version>3.6</version>
</dependency>

score -4 · Answer 4 · answered Mar 25 '13 at 11:00

-4

You could use equalsIgnoreCase(string) method found in String class for your purpose.

answered Mar 25 '13 at 11:00

Rajitha Siriwardena

2,749
1
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yes i tried.please see my code once. first i need to search in arraylist that string is there or then i have to apply that equlasignore case() butin above code how to apply that method i didnt get any idea – radha Mar 25 '13 at 11:05
1

@TimothyP OP wants insensitive case replace. Not equals. If I am wrong in downvoting, I will undo it. But I think the answer is not proper. – MysticMagicϡ Mar 25 '13 at 11:09
Well, his answer may have been better as a comment now that I think of it. You're correct – TimothyP Mar 25 '13 at 11:11

How to do a case-insensitive string replacement

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