Flash cards
Review the key moves
1/4
Core idea
What is the main idea behind Java BufferedReader?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
1Quick choice
Which statement best captures the main point of this lesson?
2Fill blank
Complete the missing token from the example code.
___ java.io.BufferedReader;3Order
Put the learning moves in the order that makes the concept easiest to apply.
Comparing File Reading Classes
Read a Text File (Line by Line)
BufferedReader and BufferedWriter
BufferedReader and BufferedWriter
BufferedReader and BufferedWriter make reading and writing text files faster.
- BufferedReader lets you read text line by line with readLine() .
- BufferedWriter lets you write text efficiently and add new lines with newLine() .
These classes are usually combined with FileReader and FileWriter , which handle opening or creating the file. The buffered classes then make reading/writing faster by using a memory buffer.
Read a Text File (Line by Line)
Use BufferedReader with FileReader to read each line of a file:
Example
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
public class Main {
public static void main(String[] args) {
try (BufferedReader br = new BufferedReader(new FileReader("filename.txt"))) {
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
} catch (IOException e) {
System.out.println("Error reading file.");
}
}
}Comparing File Reading Classes
Java gives you several ways to read files. Here's when to pick each one:
- Scanner - best for simple text . It can split text into lines, words, or numbers (e.g., nextInt() , nextLine() ).
- BufferedReader - best for large text files . It is faster, uses less memory, and can read full lines with readLine() .
- FileInputStream - best for binary files (like images, PDFs, or audio)