Question

Write a Java program which reads a text file and writes the content into a new file. During the read-write process, convert all the upper case letters into lower case ones. In other words, your programming task is to create a new file with the same content of the original file, only that all the upper case letters are converted into lower case ones in the new file.

Answer 1

Answer:

Kindly go to the explanation part for the code you seek.

Explanation:

This is the Code to Copy:

package file;

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.DataInputStream;

import java.io.FileInputStream;

import java.io.FileWriter;

import java.io.InputStreamReader;

import java.util.Scanner;

public class file

{

public static void main(String []args)

{

try

{

System.out.print("Type a file name: ");

//declare scanner for keyboard input

Scanner reader = new Scanner(System.in);

//scan the input file name

String infilename=reader.nextLine();

//define file stream

FileInputStream fstream = new FileInputStream(infilename);

DataInputStream in = new DataInputStream(fstream);

//define the buffer reader

BufferedReader br = new BufferedReader(new InputStreamReader(in));

String outfilename = "output.txt";

FileWriter fileWriter = new FileWriter(outfilename);

//declare buffer writer for file write

BufferedWriter bufferedWriter = new BufferedWriter(fileWriter);

String strLine,filename;

int status = 0;

int i=0;

//read lines one by one from input file

while ((strLine = br.readLine()) != null)

{

String temp="";

//for each character in a line

for(int k=0;k<strLine.length();k++)

{

char c;

c=strLine.charAt(k);

//if the character is uppercase

if(Character.isUpperCase(c))

//make the character lowercase and append it to the output line

temp +=Character.toLowerCase(c);

else

//character is not lowercase. append to the output line without changing it

temp += c;

}

//write the line to the file

bufferedWriter.write(temp+"\n");

}

//close the input file

in.close();

//close the output file

bufferedWriter.close();

}

catch (Exception e)

{

//System.err.println("Error: " + e.getMessage());

}

}

}