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javajsonobjectmapper

Modify a property value in json string

i have a json string like this

{
  "code": "200",
  "data": "",
  "datadetail": null,
  "message": "Khách hàng không tồn tại",
  "description": "KH_NOTFOUND:"
}

because the value of data property is "" so that the object mapper can't not map that field in to Java POJO, is that anyway to modify the value of data property to specific string like below 

 {
  "code": "200",
  "data": "no data",
  "datadetail": null,
  "message": "Khách hàng không tồn tại",
  "description": "KH_NOTFOUND:"
}

here is the error 1

detail

Can not instantiate value of type [collection type; class java.util.ArrayList, contains [simple type, class vnptpay.collection.adapter.partner.water.laichau.Datum]] from String value (''); no single-String constructor/factory method

here is my target java object class to map 

@JsonInclude(JsonInclude.Include.NON_NULL)
@JsonPropertyOrder({
"code",
"data",
"datadetail",
"message",
"description"
})
@JsonIgnoreProperties(ignoreUnknown = true)
public class GetBillResponse implements Serializable{

@JsonProperty("code")
private String code;
@JsonProperty("data")
private ArrayList<Datum> data = null;
@JsonProperty("datadetail")
private Object datadetail;
@JsonProperty("message")
private String message;
@JsonProperty("description")
private String description;
@JsonIgnore
private Map<String, Object> additionalProperties = new HashMap<String, Object>();

here is my mapping code 

ObjectMapper mapper = new ObjectMapper();
GetBillResponse obj = null;

obj = mapper.readValue(output.toString(), GetBillResponse.class);
Solution

  • Assuming output.toString() is your JSON string you could add .replace("\"\"", \"{none}\"). Java should be able to interpret this as an ArrayList with one element (maybe my syntax is wrong, but there is definitely a way to initialise an ArraList from a String).

    Edit: Now that I think about it, you probably need JSON-syntax, not Java-syntax, so .replace("\"\"", \"[]\") or something like that.