Java中的Properties类的操作(2)

public static void main(String[] args) throws IOException{
            WriteProperties("E:\\workspace\\ch01\\text.properties", "add2","2121");
    }
   
    //根据key读取value
    public static String GetValueByKey(String filePath,String key){
        Properties pps = new Properties();
        try{
            InputStream in= new BufferedInputStream(new FileInputStream(filePath));
            pps.load(in);
            String value = pps.getProperty(key);
            System.out.println(key + "=" + value);
            return value;
        }catch(IOException e){
            e.printStackTrace();
            return null;
        }
    }
   
    //读取配置文件的全部信息
    @SuppressWarnings("rawtypes")
    public static void GetAllProperties(String filePath) throws IOException{
        Properties pps = new Properties();
        InputStream in = new BufferedInputStream(new FileInputStream(filePath));
        pps.load(in);
        Enumeration num = pps.propertyNames(); //获取配置文件中的所有属性名enumeration
        while(num.hasMoreElements()){
            String key= (String)num.nextElement();
            String value=pps.getProperty(key);
            System.out.println(key + "=" + value);
        }
    }
   
    //写入Properties信息
    public static void WriteProperties(String filePath,String pKey,String pValue) throws IOException {
        Properties pps = new Properties();
        InputStream in= new FileInputStream(filePath);
        pps.load(in);
        OutputStream out = new FileOutputStream(filePath);
        pps.setProperty(pKey, pValue);
        pps.store(out, "Update " + pKey + " name");
    }
}

结果：test.properties文件

#Update add2 name
#Tue Jun 30 17:07:55 CST 2015
age=23
name=linyuhuan
weight=140
add2=2121
long=212