RKTechGame | File Reading and Writing in Java

File Reading using FileReader

Java me FileReader class ka use karke hum kisi bhi text file ka content character-wise read kar sakte hain. Ye character stream class hai.

Basic methods:

read(): Ek-ek character read karta hai.
read(char[] cbuf): Character array me ek saath multiple characters read karta hai.
close(): File stream ko band karta hai.

Example:

try {
  FileReader fr = new FileReader("input.txt");
  int ch;
  while ((ch = fr.read()) != -1) {
    System.out.print((char) ch);
  }
  fr.close();
} catch (Exception e) {
  e.printStackTrace();
}

Is example me input.txt file character by character read kar ke console me print ho rahi hai.

File Writing using FileWriter

FileWriter class ka use karke hum kisi file me character data write kar sakte hain. Agar file exist nahi karti to ye new file bana deta hai.

Basic methods:

write(String str): String ko file me likhta hai.
write(char[] cbuf): Character array ko write karta hai.
close(): File stream ko close karta hai.

Example:

try {
  FileWriter fw = new FileWriter("output.txt");
  fw.write("Yeh text output file me likha ja raha hai.");
  fw.close();
} catch (Exception e) {
  e.printStackTrace();
}

Is example me output.txt file create hoti hai aur usmein diya gaya text likha jata hai.