Convert Json Containing Map of similar list into POJO

Question

I need to convert following response into POJO

{
"abc" : [
 { 
  "a" : "",
  "b": "",
  "c" : ""
},
{ 
 "a" : "",
  "b": "",
  "c" : ""
}
],
"xyz" : [
 { 
  "a" : "",
  "b": "",
  "c" : ""
},
{ 
 "a" : "",
  "b": "",
  "c" : ""
}]
}

For inside object i have a class lets call it 'A'.

public class A{
private string a;
private string b;
private string c;
constructor..
getter..
setter..
}

My json contains many objects like "acb" and "xyz" ie list of same object type 'A' and keys for the same is not known for eg

{ "abc" [---],
"def" [---],
"ghi" [---],
"jkl" [---],
.......
"xyz" [---]
}

I have tried Using following class for the same

Public class Example{
Map<String,List<A>> response;

public Example(Map<String,List<A>> response){
this.response = response;
}

getter...
setter...
}

it does not seems to be working, I am using Object Mapper class to convert.

Example example = objectmapper.readValue(responseBody,Example.class);

Answer 1

A simple Map<List<Item>> would work:

class Item{
    private String a="";
    private String b="";
    private String c="";
    public String getA() {
        return a;
    }
    public void setA(String a) {
        this.a = a;
    }
    public String getB() {
        return b;
    }
    public void setB(String b) {
        this.b = b;
    }
    public String getC() {
        return c;
    }
    public void setC(String c) {
        this.c = c;
    }
}

To create the json:

List<Item> list = new ArrayList<Item>();
list.add(new Item());
list.add(new Item());

List<Item> list2 = new ArrayList<Item>();
list2.add(new Item());
list2.add(new Item());

Map<String,List<Item>> map = new HashMap<String,List<Item>>();
map.put("abc", list);
map.put("xyz", list);

ObjectMapper objectMapper = new ObjectMapper();
String writeValueAsString = objectMapper.writeValueAsString(map);

The reverse to load the json into a map:

String json = "{\"abc\":[{\"a\":\"val\",\"b\":\"val\",\"c\":\"val\"},{\"a\":\"val\",\"b\":\"val\",\"c\":\"val\"}],\"xyz\":[{\"a\":\"val\",\"b\":\"val\",\"c\":\"val\"},{\"a\":\"val\",\"b\":\"val\",\"c\":\"val\"}]}";
Map<String,List<Item>> map = objectMapper.readValue(json, Map.class);

So, in the end, it's very similar to what you had. It's simply the extra level of 'Example' that was causing you trouble...