Parsing JSON into custom POJO which has Map as one it's class member

Question

I have below JSON which I want to parse into below bean classes.

{
    "timeStamp": "123123123123",
    "pznFlowFlag": "true",
    "pznRequestFlag": "true",
    "sessionId": "SampleSessionId",
    "ipAddress": "172.148.0.1",
    "offers": [
    {
            "111": {
                "eep" : "44279",
                "spl_ind" : "true"},
            "121": {
                "eep" : "44520",
                "spl_ind" : "false"},
            "333": {
                "eep" : "45419",
                "spl_ind" : "false" }
    }]
}

Bean class 1

public class DistributedCookieBean {

    @JsonProperty("timeStamp")
    private String timeStamp;

    @JsonProperty("pznFlowFlag")
    private String pznFlowFlag;

    @JsonProperty("pznRequestFlag")
    private String pznRequestFlag;

    @JsonProperty("sessionId")
    private String sessionId;

    @JsonProperty("ipAddress")
    private String ipAddress;

    @JsonProperty("offers")
    private Map<String, OfferCookieBean> offers = new HashMap<String, OfferCookieBean>();

...<setters & getters>
}

Bean class 2

public class OfferCookieBean {

    @JsonProperty("eep")
    private String eep;

    @JsonProperty("spl_ind")
    private String spl_ind;

...<setters & getters>
}

Here I am not able to parse into the these Java POJOs using below code.

jsonObjMapper.readValue(jsonString, DistributedCookieBean.class);

Stacktrace:

org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of java.util.Map out of START_ARRAY token at [Source: json.txt; line: 6, column: 31] at org.codehaus.jackson.map.JsonMappingException.from(JsonMappingException.java:159) at org.codehaus.jackson.map.deser.StdDeserializationContext.mappingException(StdDeserializationContext.java:192) at org.codehaus.jackson.map.deser.MapDeserializer.deserialize(MapDeserializer.java:134) at org.codehaus.jackson.map.deser.MapDeserializer.deserialize(MapDeserializer.java:23) at org.codehaus.jackson.map.deser.SettableBeanProperty.deserialize(SettableBeanProperty.java:135) at org.codehaus.jackson.map.deser.SettableBeanProperty$MethodProperty.deserializeAndSet(SettableBeanProperty.java:221) at org.codehaus.jackson.map.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:391) at org.codehaus.jackson.map.deser.BeanDeserializer.deserialize(BeanDeserializer.java:287) at org.codehaus.jackson.map.ObjectMapper._readMapAndClose(ObjectMapper.java:1588) at org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1074) at Test.main(Test.java:29)

Thanks in advance!

Check the property name for the 'offers' field. If it does not help, post the exception stack trace. — Alexey Gavrilov
Thanks, I corrected the JSON in question. I picked up old JSON. here is stacktrace added in the original question — mangoman

Alexey Gavrilov Alexey Gavrilov · Accepted Answer · 2015-04-16T21:13:51

The error message points to the problem: the offers field is declared as a map while in JSON it is an array of maps.

Try to change Map<String, OfferCookieBean> offers = new HashMap<String, OfferCookieBean>() to List<Map<String, OfferCookieBean>> offers; and see what happens.

Parsing JSON into custom POJO which has Map as one it's class member

1 Answers