2021-09-20 IO流(Properties存取配置文件)

演示如何将流中的数据存储到集合中，想要将info.txt中的数据存到集合中进行操作
1.用一个流和info.txt文件关联
2.读取一行数据，将该行数据用“=”进行切割
3.等号左边作为键，右边作为值，存入到Properties集合中即可

import java.io.*;
import java.util.Properties;

public class PropertiesDemo2 {

    public static void main(String[] args) throws Exception {
//        method();
        loadDemo();
    }

    public static void method() throws IOException {
        BufferedReader bufr = new BufferedReader(new FileReader("E:\\info.txt"));
        String line;
        Properties prop = new Properties();
        while ((line = bufr.readLine()) != null) {
            String[] arr = line.split("=");
            System.out.println(arr[0] + "..." + arr[1]);
            prop.setProperty(arr[0], arr[1]);
        }
        bufr.close();
        System.out.println(prop);
    }

    public static void loadDemo() throws IOException {
        Properties prop = new Properties();
        FileInputStream fis = new FileInputStream("E:\\info.txt");
        // 将流中的数据加载进集合
        prop.load(fis);
        prop.setProperty("wangwu", "35");
        FileOutputStream fos = new FileOutputStream("E:\\info.txt");
        prop.store(fos, "haha");
        System.out.println(prop);
        prop.list(System.out);
        fis.close();
        fos.close();
    }

}