Properties加载设备上的数据

Properties的两个方法：

store(OutputStream out, String comments):持久化

load(InputStream inStream):加载

load(Reader reader)

store(Writer writer, String comments)

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Properties;

public class PropertyDemo {

    public static void main(String[] args) throws IOException {
        
        /*
         * 演示一下Properties的特有方法
         */
        
        methodDemo3();
    }
    
    public static void methodDemo3() throws IOException {
        
        Properties prop = new Properties();
        
        //定义读取流和数据文件关联
        FileInputStream fis = new FileInputStream("tempfile\info.properties");
        prop.load(fis);
        
        prop.setProperty("zhangsan", "12");
        
        //要将改完的数据重新持久化
        
        FileOutputStream fos = new FileOutputStream("tempfile\info.properties");
        prop.store(fos, "flush data");//第二个参数是注释的意思
        
        
        prop.list(System.out);
        
        fos.close();
        fis.close();
        
        
    }

    public static void methodDemo2() throws IOException{
        
        Properties prop = new Properties();
        
        prop.setProperty("zhangsan", "20");
        prop.setProperty("lisi", "23");
        prop.setProperty("wangwu", "10");
        
        //将集合中的数据持久化到设备上
        //需要输出流对象
        FileOutputStream fos = new FileOutputStream("tempfile\info.properties");
        
        //使用prop的store方法，
        prop.store(fos, "my demo person info");//store需要用到输出流
        
        fos.close();
        
    }
    
    public static void methodDemo(){
        
        //Properties的基本存和取
        
        //1.创建一个Properties
        Properties prop = new Properties();
        
        prop.setProperty("zhangsan", "20");
        prop.setProperty("lisi", "23");
        prop.setProperty("wangwu", "10");
        
        prop.list(System.out);//此方法对调试很有用
        
//        Set<String> set = prop.stringPropertyNames();
//        
//        for(String name:set){
//            String value = prop.getProperty(name);
//            System.out.println(name+"...."+value);
//        }
    }

}