Files I/O (via Streams)

Tags: #◇Computer Science #◇CCPROG3 #◇Files I/O (via Streams) #◇Code Snippets #◇M10

◇Key Definitions

File I/O (Input/Output) is the process of reading data from and writing data to files. In Java, this is heavily managed through Streams, which are sequences of data.

◇Theoretical Framework

Java I/O Streams are categorized into: Byte Streams: Handle I/O of raw binary data (e.g., FileInputStream, FileOutputStream). Character Streams: Handle I/O of characters, automatically managing character encoding (e.g., FileReader, FileWriter). Buffered Streams: Wrap other streams to provide buffering, improving efficiency by reducing physical I/O operations (e.g., BufferedReader, BufferedWriter).

◇Code Implementation

import java.io.*;

public class FileIOExample {
    public static void main(String[] args) {
        String fileName = "output.txt";
        
        // Writing to a file using Buffered Character Stream
        try (BufferedWriter writer = new BufferedWriter(new FileWriter(fileName))) {
            writer.write("Hello, Java I/O!");
            writer.newLine();
            writer.write("This is a second line.");
        } catch (IOException e) {
            e.printStackTrace();
        }
        
        // Reading from a file
        try (BufferedReader reader = new BufferedReader(new FileReader(fileName))) {
            String line;
            while ((line = reader.readLine()) != null) {
                System.out.println(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

◇Syntax Breakdown

try-with-resources: The try (Resource res = ...) syntax ensures that the resource is automatically closed at the end of the statement, preventing resource leaks. FileReader / FileWriter: Basic character stream classes. BufferedReader / BufferedWriter: Enhances basic streams with internal buffers.

◇Complexity Analysis

Buffered I/O operations have an amortized time complexity of O(1) per byte/character read or written, as they reduce the number of expensive system calls compared to unbuffered streams. Space complexity is proportional to the buffer size.

◇References & Navigation

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