INPUT-OUTPUT FUNCTIONS (BufferedReader Class) - Java Programming

 

Introduction:

Java programming provides various ways to handle input and output operations. One of the key classes for efficient input reading is the BufferedReader class. In this article, we'll delve into the details of the BufferedReader class, its methods, exceptions, and provide a simple yet comprehensive example to ensure everyone can grasp the concept.

 

BufferedReader Class: Efficient Input Reading

The BufferedReader class in Java is part of the java.io package and is designed to read characters from an input stream. It's particularly useful for reading large volumes of text more efficiently than using Scanner or other methods. The main reason for its efficiency is that it buffers characters in memory, reducing the overhead of reading one character at a time from the underlying stream.

 

BufferedReader Methods:

 

read(): Retrieves a solitary character in the form of an integer value.

readLine(): Reads a line of text as a string.

read(char[] cbuf, int offset, int length): Reads characters into an array.

ready(): Checks if the stream is ready for reading.

close(): Closes the stream and releases resources.

Exception Handling:

During input operations, exceptions can occur due to various reasons, such as the end of the stream or invalid input. The IOException is a common exception that needs to be handled when using the BufferedReader class. It's crucial to enclose input operations in a try-catch block to ensure graceful handling of exceptions and prevent application crashes.

 

Example: Reading a File Using BufferedReader

Let's illustrate the usage of the BufferedReader class with an example of reading a text file.

 Code :

import java.io.BufferedReader;

import java.io.FileReader;

import java.io.IOException;

 

public class BufferedReaderExample {

    public static void main(String[] args) {

        String filePath = "sample.txt"; // Replace with your file path

        try (BufferedReader reader = new BufferedReader(new FileReader(filePath))) {

            String line;

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

                System.out.println(line);

            }

        } catch (IOException e) {

            System.err.println("An error occurred: " + e.getMessage());

        }

    }

}

In this example, we import the necessary classes, create a BufferedReader instance by wrapping a FileReader, and then read each line from the file using the readLine() method. The try-with-resources statement ensures the stream is properly closed even if an exception occurs.

 

Explanation:

 

The BufferedReader is created using the FileReader to efficiently read data from the file.

The while loop iterates through each line obtained from readLine() until the end of the file is reached (indicated by a null return).

If any IOException occurs during the process, it's caught and an error message is displayed.

Conclusion:

The BufferedReader class in Java is a powerful tool for handling input reading operations, especially when dealing with large volumes of text. Its methods and exception handling mechanisms make it a reliable choice for reading data from various input sources. By using the provided example and explanations, anyone can easily understand and implement input reading using the BufferedReader class in their Java programs.