Understanding File, FileReader, FileWriter, BufferedReader, and BufferedWriter in Java

1. File Class :

• The file class is represents file or directory(folder).They used to file related operations such as creating,deleting,renaming,check whether file or folder.
• However the file does not write or read.

Example:

File file = new File("data.txt");

if(file.exists()) {
    System.out.println("File exists");
}

2.FileReader:

• The FileReader is used to read text data from a file by character by character.

• It is suitable for reading small text files.

Example:

FileReader fr = new FileReader("data.txt");

int ch;
while((ch = fr.read()) != -1) {
    System.out.print((char) ch);
}

fr.close();

1. FileWriter :

• The FileWriter is used to write text data into a file . If the file does not exist ,java creates file automatically.

Example:

FileWriter fw = new FileWriter("data.txt");

fw.write("Hello Java");

fw.close();

1. BufferedReader :

• The BufferReader is used to improves reading performance by instead of using internal buffer.
• Instead of accessing the file for every character, it reads a larger block of data into memory. It also provides the convenient readLine() method.

Example:

BufferedReader br =
    new BufferedReader(
        new FileReader("data.txt"));

String line;

while((line = br.readLine()) != null) {
    System.out.println(line);
}

br.close();

5.BufferedWriter :

-The BufferedWriter is used to write text data improves writing performance by storing data in a buffer before writing it to the file.

• The reduces the number of disk operatins and makes file writing faster.

Example:

BufferedWriter bw =
    new BufferedWriter(
        new FileWriter("data.txt"));

bw.write("Hello");
bw.newLine();
bw.write("Java");

bw.close();