I'm getting a json array holding objects looking like this:
[
{
"id": "1",
"name": "some name",
"url": "some url",
"active": true
}, {
"id": "2",
"name": "some other name",
"url": "some other url",
"active": true
}
]
Now, I want to be able to deserialize that array into a java object holding a list of the objects in the array. I have made a custom deserializer looking like this:
public class ListSerializer extends JsonDeserializer<List<Provider>>{
private static final long serialVersionUID = 9114152571639338391L;
@Override
public List<Provider> deserialize(JsonParser jsonParser,
DeserializationContext arg1) throws IOException, JsonProcessingException {
// TODO Auto-generated method stub
final ObjectCodec objectCodec = jsonParser.getCodec();
final JsonNode listOrObjectNode = objectCodec.readTree(jsonParser);
final List<Provider> result = new ArrayList<Provider>();
for (JsonNode node : listOrObjectNode) {
result.add(objectCodec.treeToValue(node, Provider.class));
}
return result;
}
}
And the class holding the list looks like this:
public class ProviderList {
@JsonDeserialize(using = ListSerializer.class)
private List<Provider> providerList;
public List<Provider> getProviderList() {
return providerList;
}
public void setProviderList(final List<Provider> providerList) {
this.providerList = providerList;
}
}
I am obviously doing something wrong, because I'm getting this error:
Can not deserialize instance of com.wirelesscar.trailser.v1_0.domain.ProviderList out of START_ARRAY token at [Source: [{"id":"1","name":"Posttrack","url":"http:\dev.posttrack.com","active":true},{"id":"2","name":"Trackunit","url":"http:\dev.trackunit.com","active":true}]; line: 1, column: 1]
How can I do this properly?
You can deserialize directly to a list by using the TypeReference wrapper.
@Data
public class Provider {
private Long id;
private String name;
private String url;
private boolean active;
}
@Data
public class ProviderList {
List<Provider> providerList;
}
public class JsonTest {
@Test
public void test() {
String json = "[{\n" +
" \"id\": \"1\",\n" +
" \"name\": \"some name\",\n" +
" \"url\": \"some url\",\n" +
" \"active\": true\n" +
" }, {\n" +
" \"id\": \"2\",\n" +
" \"name\": \"some other name\",\n" +
" \"url\": \"some other url\",\n" +
" \"active\": true\n" +
" }\n" +
"]";
ObjectMapper mapper = new ObjectMapper();
try {
List<Provider> providerList = mapper.readValue(json, new TypeReference<List<Provider>>(){});
for (Provider provider : providerList) {
System.out.println(provider);
}
ProviderList list = new ProviderList();
list.setProviderList(providerList);
} catch (IOException e) {
e.printStackTrace();
}
}
}