How to replace first occurrence of string in Java

I want to replace first occurrence of String in the following.

  String test = "see Comments, this is for some test, help us"

**If test contains the input as follows it should not replace

1. See Comments, (with space at the end)
2. See comments,
3. See Comments**

I want to get the output as follows,

 Output: this is for some test, help us

Thanks in advance,

You can use replaceFirst(String regex, String replacement) method of String.

You should use already tested and well documented libraries in favor of writing your own code.

org.apache.commons.lang3.
  StringUtils.replaceOnce("coast-to-coast", "coast", "") = "-to-coast"

Javadoc

• https://commons.apache.org/proper/commons-lang/apidocs/org/apache/commons/lang3/StringUtils.html#replaceOnce-java.lang.String-java.lang.String-java.lang.String-

There's even a version that is case insensitive (which is good).

Maven

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
    <version>3.7</version>
</dependency>

Credits

My answer is an augmentation of: https://stackoverflow.com/a/10861856/714112

You can use following statement to replace first occurrence of literal string with another literal string:

String result = input.replaceFirst(Pattern.quote(search), Matcher.quoteReplacement(replace));

However, this does a lot of work in the background which would not be needed with a dedicated function for replacing literal strings.

Use substring(int beginIndex):

String test = "see Comments, this is for some test, help us";
String newString = test.substring(test.indexOf(",") + 2);
System.out.println(newString);

OUTPUT:

> this is for some test, help us

You can use following method.

public static String replaceFirstOccurrenceOfString(String inputString, String stringToReplace,
        String stringToReplaceWith) {

    int length = stringToReplace.length();
    int inputLength = inputString.length();

    int startingIndexofTheStringToReplace = inputString.indexOf(stringToReplace);

    String finalString = inputString.substring(0, startingIndexofTheStringToReplace) + stringToReplaceWith
            + inputString.substring(startingIndexofTheStringToReplace + length, inputLength);

    return finalString;

}

Following link provide examples for replacing first occurrence of string using with and without regular expressions.

Use String replaceFirst to swap the first instance of the delimiter to something unique:

String input = "this=that=theother"
String[] arr = input.replaceFirst("=", "==").split('==',-1);
String key = arr[0];
String value = arr[1];
System.out.println(key + " = " + value);

You can also use this method in node.js;

public static String replaceFirstOccurance(String str, String chr, String replacement){
    String[] temp = str.split(chr, 2);
    return temp[0] + replacement + temp[1];
}