How to read data from text in java

How to read data from a text file? Create a File object to specify the file to read. Create a Scanner object to act as a scanner for reading files. Use the nextLine() or next() method to read data by line or word. Use the close() method to close the Scanner to release resources.

Reading data from text

How to read data from a text file?

Reading data from a text file using Java can use the following steps:

1. Create a File object: This will Specify the file to read.
2. Create a Scanner object: This will be used as a scanner to read files.
3. Use the nextLine() or next() method: These methods will read data by line or by word.
4. Use the close() method to close Scanner: This will release resources.

Code example:

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class ReadFromFile {

    public static void main(String[] args) {
        try {
            // 创建 File 对象
            File file = new File("data.txt");

            // 创建 Scanner 对象
            Scanner scanner = new Scanner(file);

            // 按行读取数据
            while (scanner.hasNextLine()) {
                String line = scanner.nextLine();
                System.out.println(line);
            }

            // 按单词读取数据
            while (scanner.hasNext()) {
                String word = scanner.next();
                System.out.println(word);
            }

            // 关闭 Scanner
            scanner.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }
}

Other methods:

In addition to using Scanner In addition, you can also use the following methods to read data from text files:

• BufferedReader: Provides a higher level of buffering, which can increase reading speed .
• FileReader: Character stream, buffering must be handled manually.
• NIO (Non-blocking I/O): A high-level I/O API that provides asynchronous reading.

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