How to annotate enum fields for deserialization using Jackson json

Question

I am using REST web service/Apache Wink with Jackson 1.6.2. How do I annotate an enum field so that Jackson deserializes it?

Inner class

public enum          


        

Answer 1

The following may work if the enumeration is an array or not. (Only for deserialization)

package com.stack.model;

import java.util.HashMap;
import java.util.Map;

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonPropertyOrder;

import lombok.Data;

@Data
@JsonInclude(JsonInclude.Include.NON_NULL)
@JsonIgnoreProperties(ignoreUnknown = true)
@JsonPropertyOrder({ "success", "my-enums" })
public class MyObjectJSON {

    @JsonProperty("sucess")
    private boolean success;

    @JsonProperty("my-enums")
    private MyEnum[] myEnums;


    static enum MyEnum {
        Enum1, Enum2, Enum3, Enum4, EnumN;

        private static Map myEnumsMap = new HashMap(5);

        static {
            myEnumsMap.put("enum1-val", Enum1);
            myEnumsMap.put("enum2-val", Enum2);
            myEnumsMap.put("enum3-val", Enum3);
            myEnumsMap.put("enum4-val", Enum4);
            myEnumsMap.put("enumn-val", EnumN);
        }

        @JsonCreator
        public static MyEnum forValue(String value) {
            return myEnumsMap.get(value.toLowerCase());
        }
    }
}

To consider:

1. The @Data annotation generates setters, getters, toString, etc.

2. @JsonProperty("my-enums") private MyEnum[] myEnums, this is the way to annotate with jackson the field that is of type Enum ( It works if it is an array or not).

3. MyEnum is the enumeration of the values ​​to be mapped of the JSON object, suppose the following object:

   { "sucess": true, "my-enums": ["enum1-val", "enum3-val"] }

4. The forValue function allows mapping the string values ​​of the array to Enum, it is annotated with @JsonCreator to indicate a construction factory used in deserialization.