properties to json (通过前缀手动创建json, bean) propsutils

问题:  动态修改配置文件，让服务感知，动态刷新内存中的数据，立马生效

　　　此时需要手动将properties 转 bean ,  替换内存数据

eg:

properties:

name = sea
addr= sz
a.mylist[0].a = l1
a.mylist[0].b = l2
...

json:

{
  "mylist": [
    {
      "b": "l2",
      "a": "l1"
    },
    {
      "b": "l22",
      "a": "l11"
    }
  ],
  "name": "sea",
  "addr": "sz"
}

此处采用第三方依赖:(建议自己实现)

依赖：

   <dependency>
        <groupId>pl.jalokim.propertiestojson</groupId>
        <artifactId>java-properties-to-json</artifactId>
        <version>5.2.1</version>
    </dependency>

    <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.79</version>
    </dependency>

使用：

import pl.jalokim.propertiestojson.util.PropertiesToJsonConverter;

...
// properties as Map<String,String>, java.util.Properties, java.io.InputStream
String json = new PropertiesToJsonConverter().convertToJson(properties);

// convert from file
String jsonFromProperties = new PropertiesToJsonConverter().convertPropertiesFromFileToJson("/home/user/file.properties");
String jsonFromProperties2 = new PropertiesToJsonConverter().convertPropertiesFromFileToJson(new File("/home/user/file.properties"));

// for map with Object as value, String as key
Map<String,Object> valuesAsObjectMap = new HashMap<>();
String jsonFromProperties3 = new PropertiesToJsonConverter().convertFromValuesAsObjectMap(valuesAsObjectMap);

// converter Instance can be gathered through PropertiesToJsonConverterBuilder class, it has a few method for customization
PropertiesToJsonConverter propsToJsonConverter = PropertiesToJsonConverterBuilder.builder().build();

PropsUtils:

    @ToString
    @Data
    static class Sea {
        private String name;
        private String addr;
        private List mylist;
    }

    @Test
    public void testName() throws Exception {
        Properties properties = new Properties();
        properties.put("user1.name", "sea");
        properties.put("user.name", "sea");
        properties.put("user.addr", "sz");
        properties.put("user.mylist[0].a", "l1");
        properties.put("user.mylist[0].b", "l2");
        properties.put("user.mylist[1].a", "l11");
        properties.put("user.mylist[1].b", "l22");
        Enumeration<Object> keys = properties.keys();
        String prefix = "user";
        Sea propsToBean = propsToBean(properties, prefix, Sea.class);
        System.err.println(propsToBean);
    }

    public static String propsToJson(Properties properties,String prefix) throws Exception {
        Enumeration<Object> keys = properties.keys();
        Properties newProps = new Properties();
        while ( keys.hasMoreElements()) {
            String key = (String) keys.nextElement();
            if(key.startsWith(prefix+".")) {
                newProps.put(key.substring(prefix.length()+1),properties.get(key));
            }
        }
        String json = new PropertiesToJsonConverter().convertToJson(newProps);
        return json;
    }
    
    
    public static <T> T  propsToBean(Properties properties,String prefix,Class<T> clazz) throws Exception {
        Enumeration<Object> keys = properties.keys();
        Properties newProps = new Properties();
        while ( keys.hasMoreElements()) {
            String key = (String) keys.nextElement();
            if(key.startsWith(prefix+".")) {
                newProps.put(key.substring(prefix.length()+1),properties.get(key));
            }
        }
        String json = new PropertiesToJsonConverter().convertToJson(newProps);
         T bean = JSON.parseObject(json,clazz);
         return  bean;
    }