Json 处理技巧

将对象转为 JSON 字符串

ObjectMapper objectMapper = new ObjectMapper();
String str = objectMapper.writeValueAsString(javaObj);

将 JSON 字符串转为 Map

JavaType valueType = objectMapper.getTypeFactory()
    .constructParametricType(HashMap.class, String.class, Object.class);
HashMap<String, Object> map = objectMapper.readValue(str, valueType);

将 JSON 字符串转为 List

JavaType valueType = objectMapper.getTypeFactory()
     .constructParametricType(ArrayList.class, Person.class);
List<Person> list = objectMapper.readValue(str, valueType);