Question

Object Class:

class User{
    public String name;
    public String password;
}

JSON:

{ sc:"200", msg:"something", userInfo:{name:"n", password:"p"} }

I want to get results like this:

Map->contains 3 key-value
"sc"="200"
"msg"="something"
"userInfo"=User(Object Class)

How can I do this? Or, how can I get it to use another JAR tools package?

Answer 1

You have to choose if you want “untyped” (Maps, Lists, wrappers), which are easy enough to get:

Map<String,Object> map = new ObjectMapper().readValue(json, Map.class);

or POJOs. The thing is, mapper really can’t know that you want “userInfo” to map to a specific object, but other values to something else.

But I would rather just create another class, like:

public class Request {
   public int sc;
   public String message;
   public User userInfo;
   // and/or getters, setters, if you prefer
}

and bind to that:

Request req = new ObjectMapper().readValue(json, Request.class);

Why mess with inconvenient Maps when you can have real POJOs, right? 🙂