How to replace all occurrences of a word in a string with another word in java?

The replaceAll() method of the String class accepts two strings, One representing a regular expression to find a string and the other representing a replacement string.

And, replaces all the matched sequences with the given String. Therefore, to replace a particular word with another in a String −

• Get the required String.

• Invoke the replace all method on the obtained string by passing, a regular expression representing the word to be replaced (within word boundaries “\b”) and a replacement string as parameters.

• Retrieve the result and print it.

Example

import java.io.File;
import java.io.IOException;
import java.util.Scanner;
public class ReplacingWords {
   public static void main(String[] args) throws IOException {
      Scanner sc = new Scanner(new File("D://sample.txt"));
      String input;
      StringBuffer sb = new StringBuffer();
      while (sc.hasNextLine()) {
         input = sc.nextLine();
         sb.append("
"+input);
      }
      String contents = sb.toString();
      System.out.println("Contents of the string: "+contents);
      contents = contents.replaceAll("\bTutorials point\b", "TP");
      System.out.println("Contents of the string after replacement: ");
      System.out.println(contents);
   }
}

Output

Contents of the string:
Tutorials point originated from the idea that there exists a class of readers who respond better to on-line content
and prefer to learn new skills at their own pace from the comforts of their drawing rooms.
At Tutorials point we provide high quality learning-aids for free of cost.
Tutorials point recently developed an app to help students from 6th to 12th.
Contents of the string after replacement:
TP originated from the idea that there exists a class of readers who respond better to on-line content
and prefer to learn new skills at their own pace from the comforts of their drawing rooms.
At TP we provide high quality learning-aids for free of cost.
TP recently developed an app to help students from 6th to 12th.