Java Files readString()

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In this guide, you will learn about the Files readString() method in Java programming and how to use it with an example.

1. Files readString() Method Overview

Definition:

The readString() method belongs to the Files class in Java and is introduced in Java 11. This method is used to read all content from a file into a string, making it convenient to read file content with a single line of code.

Syntax:

1. Files.readString(Path path) throws IOException
2. Files.readString(Path path, Charset cs) throws IOException

Parameters:

- path: The Path object that locates the file to read.

- cs: Optional. The Charset to be used to decode the bytes to characters. If not provided, the UTF-8 charset is used by default.

Key Points:

- The method reads all the content of the file and returns it as a single String.

- The Charset for decoding can be optionally specified, default is UTF-8.

- Throws IOException if an I/O error occurs while reading from the file.

- Useful for reading small files, but care should be taken with large files to avoid OutOfMemoryError.

2. Files readString() Method Example

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

public class ReadStringExample {
    public static void main(String[] args) {
        Path filePath = Paths.get("example.txt");

        try {
            String content = Files.readString(filePath);
            System.out.println("Content read from the file:");
            System.out.println(content);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Output:

Content read from the file:
Java Files.writeString() Example

Explanation:

In this example, we specify a path to the file we want to read. We use the Files.readString() method to read the content of the file into a string. Then, we print the content to the console. If the file is not found or an I/O error occurs, the method will throw an IOException.