Java中用Properties类读取配置文件 键值对

 案例：

package demo1;

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.Properties;

public class T {
    public static void main(String[] args) {
        Properties properties = new Properties();
        FileReader fr = null;
        try {
            //fr = new FileReader("C:\\Users\\ASDS\\Desktop\\class1.txt");
            fr = new FileReader("src\\demo1\\class2.txt");
            properties.load(fr); //从class.txt文件中获取键值对
            fr.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        String username = properties.getProperty("username");//get class.text className value
        String password = properties.getProperty("password");//get class.text  methodName value

        System.out.println(username);
        System.out.println(password);

    }

}

class2.txt 文件内容：

username = 123
password = 0000