So lesen Sie Daten in Java

import java.util.Scanner;  
  
public class Main {  
    public static void main(String[] args) {  
        Scanner scanner = new Scanner(System.in);  
        System.out.println("请输入一个整数：");  
        int number = scanner.nextInt(); // 读取一个整数  
        System.out.println("你输入的整数是：" + number);  
  
        System.out.println("请输入一个字符串：");  
        String text = scanner.nextLine(); // 读取一行文本  
        System.out.println("你输入的字符串是：" + text);  
  
        scanner.close(); // 关闭Scanner对象  
    }  
}

import java.io.BufferedReader;  
import java.io.FileReader;  
import java.io.IOException;  
  
public class Main {  
    public static void main(String[] args) {  
        BufferedReader reader = null;  
        try {  
            reader = new BufferedReader(new FileReader("path_to_your_file.txt"));  
            String line;  
            while ((line = reader.readLine()) != null) {  
                System.out.println(line); // 读取并打印文件的每一行  
            }  
        } catch (IOException e) {  
            e.printStackTrace();  
        } finally {  
            if (reader != null) {  
                try {  
                    reader.close();  
                } catch (IOException e) {  
                    e.printStackTrace();  
                }  
            }  
        }  
    }  
}

import java.io.IOException;  
import java.nio.file.Files;  
import java.nio.file.Paths;  
import java.util.List;  
  
public class Main {  
    public static void main(String[] args) {  
        try {  
            List<String> lines = Files.readAllLines(Paths.get("path_to_your_file.txt"));  
            for (String line : lines) {  
                System.out.println(line); // 读取并打印文件的每一行  
            }  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
    }  
}

import java.sql.Connection;  
import java.sql.DriverManager;  
import java.sql.ResultSet;  
import java.sql.Statement;  
  
public class Main {  
    public static void main(String[] args) {  
        String url = "jdbc:mysql://localhost:3306/your_database";  
        String user = "your_username";  
        String password = "your_password";  
  
        try (Connection conn = DriverManager.getConnection(url, user, password);  
             Statement stmt = conn.createStatement();  
             ResultSet rs = stmt.executeQuery("SELECT * FROM your_table")) {  
  
            while (rs.next()) {  
                int id = rs.getInt("id");  
                String name = rs.getString("name");  
                // ... 读取其他字段  
                System.out.println("ID: " + id + ", Name: " + name);  
            }  
        } catch (Exception e) {  
            e.printStackTrace();  
        }  
    }  
}