JSON request to Java data structure

Question

I have following JSON request:

{
    "one":{
        "key":"value",
        "key":"value",
        "key":"value"
    },
    "two":[
        "value"
    ],
    "three":[
        "value"
    ],
    "four":[
        "value"
    ]
}

How can I represent it as a Java object/data structure? I can normally take JSON starting from "two" and handle it as follows:

@RequestBody Map<String, List<String>> inputParams

any suggestions?

[http://stackoverflow.com/questions/1688099/converting-json-to-java](http://stackoverflow.com/questions/1688099/converting-json-to-java) — ma3stro, Aug 15 '16 at 10:33
@ma3stro nope, this isn't method I want to use. Something better from Spring, JAXB etc. — alalambda, Aug 15 '16 at 10:41

score 0 · Accepted Answer · answered Aug 15 '16 at 10:48

0

Try this...

 Map<String, Object> inputParams;

 InnerObj innerObj = (InnerObj)inputParams.get("one");
 List<String> secondList = (List)inputParams.get("two");
 List<String> thirdLisr = (List)inputParams.get("three");
 '''

where

class InnerObj {
    String key1;
    String key2;
}

answered Aug 15 '16 at 10:48

Ravindra Devadiga

692
1
6
14

Thanks, this seems legit and appropriate for me as I don't want to use a lot of external libs. – alalambda Aug 15 '16 at 12:10
but there's one issue: i'm getting java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to SomeObject. – alalambda Aug 15 '16 at 12:37

score 0 · Answer 2 · answered Aug 15 '16 at 11:12

You can use Google GSON https://github.com/google/gson and parse your json to POJO and than use it. For example:

{ "key1":"value1", "key2":"value2", "key3":"value3" }

Gson gson = new Gson();
MyObj myObj = gson.fromJson(jsonObj, MyObj.class);

Where MyObj.java:

public class MyObj {
    String key1;
    String key2;
    String key3;
}

And in your controller you can use @RequestParam(value = "jsonObjFromClient") String jsonObj annotation.

JSON request to Java data structure

2 Answers2