1.4. NIO in Action: Practical Example

import java.io.*;
public class FileReaderExample {
    public static void main(String[] args) {
        try (BufferedReader reader = new BufferedReader(new FileReader("sample.txt"))) {
            String line;
            while ((line = reader.readLine()) != null) {
                System.out.println(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

In this chunk, we see an example of how to read from a file using the Java I/O API. The code imports necessary classes from the java.io package. It defines a class named FileReaderExample with a main method. Inside the main method, a BufferedReader is used to read text from a file named 'sample.txt'. The BufferedReader is wrapped around a FileReader, which is essentially a bridge to read character data from files. The try-with-resources statement automatically closes the reader, ensuring that resources are managed properly. A loop continues until there are no more lines (when readLine() returns null), printing each line read from the file to the console. If any IOException occurs, it prints the stack trace for debugging purposes.

Imagine reading a book. You flip through pages one by one, reading paragraphs aloud. In this analogy, the BufferedReader is like your eyes, moving across the lines, while the book is the file on your computer. The act of reading each line is akin to the program printing the content line by line onto the console.

import java.nio.file.*;
import java.io.IOException;
public class NIOFileReaderExample {
    public static void main(String[] args) {
        Path path = Paths.get("sample.txt");
        try {
            Files.lines(path).forEach(System.out::println);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

This chunk presents a similar task, but it uses the New I/O (NIO) API. The code imports classes from java.nio.file and java.io. The main component here is the Path object, which represents the file path of 'sample.txt'. Using the static Files.lines(path) method, it reads all lines of the file lazily, meaning that it processes each line as it's needed rather than loading the entire file into memory first. The forEach method is then invoked on the stream of lines, which prints each line to the console. This example also includes error handling for IOException to catch any issues that may arise when attempting to read the file.

Consider this scenario like opening a subscription to an online magazine. You don't download all articles at once; instead, you read each article as you click on it. The Files.lines method is like opening a new article, allowing you to read it only when you're ready, which is more efficient than printing the entire magazine at once.

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