Read plain text file in Java

Approach 1: Using Files.readAllBytes method

byte[] bytes = Files.readAllBytes(Paths.get(filePath));

String data = new String(bytes, "utf-8");

App.java

package com.sample.app;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;

public class App {

 public static void printFileContents(String filePath) throws IOException {
  if (filePath == null || filePath.isEmpty()) {
   System.out.println("filePath can't be null or empty");
   return;
  }

  byte[] bytes = Files.readAllBytes(Paths.get(filePath));
  String data = new String(bytes, "utf-8");
  System.out.println(data);

 }

 public static void main(String args[]) throws IOException {
  printFileContents("/Users/krishna/Desktop/learn.txt");
 }
}

Approach 2: Using Files.readAllLines() method

List<String> fileContent = Files.readAllLines(Paths.get(filePath));

App.java

package com.sample.app;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.List;

public class App {

 public static void printFileContents(String filePath) throws IOException {
  if (filePath == null || filePath.isEmpty()) {
   System.out.println("filePath can't be null or empty");
   return;
  }

  List<String> fileContent = Files.readAllLines(Paths.get(filePath));
  for (String content : fileContent) {
   System.out.println(content);
  }

 }

 public static void main(String args[]) throws IOException {
  printFileContents("/Users/krishna/Desktop/learn.txt");
 }
}

Approach 3: Using Files.lines

Files.lines(Paths.get(filePath)).forEach(System.out::println);

App.java

package com.sample.app;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;

public class App {

 public static void printFileContents(String filePath) throws IOException {
  if (filePath == null || filePath.isEmpty()) {
   System.out.println("filePath can't be null or empty");
   return;
  }

  Files.lines(Paths.get(filePath)).forEach(System.out::println);

 }

 public static void main(String args[]) throws IOException {
  printFileContents("/Users/krishna/Desktop/learn.txt");
 }
}

Approach 4: Using BufferedReader

try (BufferedReader br = new BufferedReader(new FileReader(filePath));) {

         while ((line = br.readLine()) != null) {

                  System.out.println(line);

         }

}

App.java

package com.sample.app;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

public class App {

 public static void printFileContents(String filePath) throws IOException {
  String line;

  try (BufferedReader br = new BufferedReader(new FileReader(filePath));) {

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

  }

 }

 public static void main(String args[]) throws IOException {
  printFileContents("/Users/krishna/Desktop/learn.txt");
 }
}

Approach 5: Using Scanner

try (Scanner in = new Scanner(new FileReader(filePath))) {

         while (in.hasNext()) {

                  System.out.println(in.next());

         }

}

App.java

package com.sample.app;

import java.io.FileReader;
import java.io.IOException;
import java.util.Scanner;

public class App {

 public static void printFileContents(String filePath) throws IOException {
  try (Scanner in = new Scanner(new FileReader(filePath))) {
   while (in.hasNext()) {
    System.out.println(in.next());
   }
  }

 }

 public static void main(String args[]) throws IOException {
  printFileContents("/Users/krishna/Desktop/learn.txt");
 }
}

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