Question

我有基于Jersey框架的RESTful服务。

我需要序列化和反序列化一些包含枚举字段的对象。

我写了两个方法并用@JsonValue和@JsonCreator注释了它们。但泽西岛没有显示枚举字段？

我的枚举对象：

@XmlRootElement
public class RecipientWrapper{
    @ApiModelProperty(hidden = true)
    private Recipient recipient;

    private String name;
    private String address;
    private RecipientType type;

    public RecipientWrapper(){}

    public RecipientWrapper(String name, String address, Message.RecipientType type) {
        recipient = new Recipient(name, address, type);
    }

    @XmlTransient
    public Recipient getRecipient(){
        if (recipient == null && name != null && address != null){
            if (type != null){
                recipient = new Recipient(name, address, type.toMsgRecipientTypeValue());
            }
            else{
                recipient = new Recipient(name, address, Message.RecipientType.TO);
            }
        }
        return recipient;
    }

    public void setRecipient(Recipient recipient){
         this.recipient = recipient;
    }

    public String getName(){
        return recipient.getName();
    }

    public String getAddress(){
        return recipient.getAddress();
    }

    public Message.RecipientType getType(){
        return recipient.getType();
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public void setType(RecipientType type) {
        this.type = type;
    }

    public enum RecipientType {
        TO,
        CC,
        BCC;

        private static Map<String, RecipientType> nameMap = new HashMap<String, RecipientType>();
        private static Map<RecipientType, Message.RecipientType> msgRecipientType = new HashMap<RecipientType, Message.RecipientType>();

        static{
            nameMap.put("TO", TO);
            nameMap.put("CC", CC);
            nameMap.put("BCC", BCC);

            msgRecipientType.put(TO, Message.RecipientType.TO);
            msgRecipientType.put(CC, Message.RecipientType.CC);
            msgRecipientType.put(BCC, Message.RecipientType.BCC);
        }

        @JsonCreator
        public static RecipientType forValue(String value){
            return nameMap.get(StringUtils.upperCase(value));
        }

        @JsonValue
        public String toValue(){
            for (Map.Entry<String, RecipientType> entry: nameMap.entrySet()){
                if (entry.getValue() == this){
                    return entry.getKey();
                }
            }
            return null;
        }

        public Message.RecipientType toMsgRecipientTypeValue(){
            for (Map.Entry<RecipientType, Message.RecipientType> entry: msgRecipientType.entrySet()){
                if (entry.getKey() == this){
                    return entry.getValue();
                }
            }
            return null;
        }
    }
}

gradle依赖项：

compile 'javax.ws.rs:jsr311-api:1.1.1'

compile 'com.sun.jersey:jersey-server:1.18.1'
compile 'com.sun.jersey:jersey-servlet:1.18.1'
compile 'com.sun.jersey:jersey-bundle:1.18.1'
compile 'io.swagger:swagger-jersey-jaxrs:1.5.0'

compile 'org.antlr:stringtemplate:4.0.2'
compile 'org.freemarker:freemarker:2.3.22'
compile 'org.apache.velocity:velocity:1.7'

compile 'org.codemonkey.simplejavamail:simple-java-mail:2.2'

compile 'org.slf4j:slf4j-simple:1.7.12'
compile 'org.slf4j:slf4j-api:1.7.12'

compile 'org.codehaus.jackson:jackson-mapper-asl:1.9.13'

JSON输出：

{
  "address": "mymail@gmail.com",
  "name": "My name"
}

为什么泽西岛不显示枚举字段？

Answer 1

问题是@JsonValue注释。如果你删除它 - 它会工作。

示例：

public class A {
    private String type;
    private RecipientType recipientType;

    public A(String type, RecipientType recipientType) {
        this.type = type;
        this.recipientType = recipientType;
    }

    public String getType() {
        return type;
    }

    public RecipientType getRecipientType() {
        return recipientType;
    }

    public enum RecipientType {
        TO,
        CC,
        BCC;
    }
}

序列化时我得到了

{"type":"a","recipientType":"BCC"}

杰克逊本身知道处理枚举，你不需要任何特别的东西。添加@JsonValue只会破坏它。

为什么注释@JsonValue在泽西岛不起作用？

1 个答案: