How to find and replace a given string with new string in a file

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;

public class ReplaceWordInFile {

	public static void main(String[] args) throws IOException {

		String lineRead;
		/* Display the current sampleFile.txt file contents */
		displayFileContent("C:\\Users\\Nagendra\\sampleFile.txt","old");

		/* Re-open the same sampleFile.txt file using BufferedReader and FileReader,
		to search for a given word in each line of this file */

		FileReader fileRead=new FileReader("C:\\Users\\Nagendra\\sampleFile.txt");
		@SuppressWarnings("resource")
		BufferedReader  fileToRead = new BufferedReader(fileRead);
		System.out.println();
		Scanner inpStr=new Scanner(System.in);
		System.out.print("Enter the String to be searched in the given file: ");
		String strToSrch=inpStr.next();

		System.out.print("Enter the String to be replaced in the given file: ");
		String strToReplace=inpStr.next();
		System.out.println("\n");


		/* Open the new sampleFileUpdated.txt file using BufferedWriter and FileWriter */
		FileWriter fWrite=new FileWriter("C:\\Users\\Nagendra\\SampleFileUpdated.txt");
		BufferedWriter  fileToWrite = new BufferedWriter(fWrite);

		StringBuffer lineReadBuff= new StringBuffer();

		/* Read line by line and search for the given word in each line of sampleFile.txt
		 * using the string buffer methods. Call the function parseEachLine() */

		while ((lineRead= fileToRead.readLine()) != null) {
			lineReadBuff.append(lineRead);

			/*Write the new line into the sampleFileUpdated.txt file after
			replacing with a given word in each line of sampleFile.txt file*/

			fileToWrite.write(parseEachLine(lineReadBuff,strToSrch,strToReplace));
			lineReadBuff.delete(0, lineReadBuff.length());
		}
		fileToWrite.close();

		/* Display the newly created sampleFileUpdated.txt file contents */
		displayFileContent("C:\\Users\\Nagendra\\SampleFileUpdated.txt","new");
		inpStr.close();
	}

	private static String parseEachLine(StringBuffer lineRd,String strSrch,String strReplace){

		int startIndex=0,foundIndex=0;
		/* Search for the give word in each line multiple times
		    with the help of the indexOf method */

		while (foundIndex != -1) {
			foundIndex=lineRd.indexOf(strSrch,startIndex);
			if (foundIndex != -1) {
				lineRd.delete(foundIndex, foundIndex+strSrch.length());
				lineRd.insert(foundIndex, strReplace);
				startIndex=foundIndex+strReplace.length();
			}
		}
		return lineRd.toString()+"\n";
	}

	private static void displayFileContent(String filePath, String neworold) throws IOException {

		/* Display the sample file contents to the console using the
		BufferedReader and FileReader */		

		FileReader fRead=new FileReader(filePath);
		@SuppressWarnings("resource")
		BufferedReader  fileToRd = new BufferedReader(fRead);
		String lineRead;

		System.out.println("The contents of the "+neworold+" file are below");
		System.out.println("----------------------------------");
		while ((lineRead= fileToRd.readLine()) != null)
			System.out.println(lineRead);
		fileToRd.close();
	}
}