jackson出现错误 Unrecognized field，几种处理方法

错误堆栈信息如下:

org.codehaus.jackson.map.exc.UnrecognizedPropertyException: Unrecognized field "HPYS" (Class com.traffic.entity.BusBaseInfo), not marked as ignorable
 at [Source: java.io.StringReader@76c5faf5; line: 1, column: 84] (through reference chain: com.traffic.entity.BusBaseInfoBody["result"]->com.traffic.entity.BusBaseInfo["HPYS"])
	at org.codehaus.jackson.map.exc.UnrecognizedPropertyException.from(UnrecognizedPropertyException.java:53)
	at org.codehaus.jackson.map.deser.StdDeserializationContext.unknownFieldException(StdDeserializationContext.java:246)
	at org.codehaus.jackson.map.deser.StdDeserializer.reportUnknownProperty(StdDeserializer.java:604)
	at org.codehaus.jackson.map.deser.StdDeserializer.handleUnknownProperty(StdDeserializer.java:590)
	at org.codehaus.jackson.map.deser.BeanDeserializer.handleUnknownProperty(BeanDeserializer.java:689)
	at org.codehaus.jackson.map.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:514)
	at org.codehaus.jackson.map.deser.BeanDeserializer.deserialize(BeanDeserializer.java:350)
	at org.codehaus.jackson.map.deser.CollectionDeserializer.deserialize(CollectionDeserializer.java:120)
	at org.codehaus.jackson.map.deser.CollectionDeserializer.deserialize(CollectionDeserializer.java:97)
	at org.codehaus.jackson.map.deser.CollectionDeserializer.deserialize(CollectionDeserializer.java:26)
	at org.codehaus.jackson.map.deser.SettableBeanProperty.deserialize(SettableBeanProperty.java:252)
	at org.codehaus.jackson.map.deser.SettableBeanProperty$MethodProperty.deserializeAndSet(SettableBeanProperty.java:356)
	at org.codehaus.jackson.map.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:494)
	at org.codehaus.jackson.map.deser.BeanDeserializer.deserialize(BeanDeserializer.java:350)
	at org.codehaus.jackson.map.ObjectMapper._readMapAndClose(ObjectMapper.java:2395)
	at org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1595)
	at com.trafficframework.core.util.JSONHelper.fromJsonToObject(JSONHelper.java:72)
	at com.traffic.client.GetCarInfoUtil.main(GetCarInfoUtil.java:188)

1、请求的JSON里面字段多余映射的实体类，可以通过在类的顶部添加@JsonIgnoreProperties，2.0版本引入

import org.codehaus.jackson.annotate.JsonIgnoreProperties;

2、属性大小写问题，如下 属性全部大写，JackSon 默认是通过驼式命名法 处理 比如 nickName 这样儿，有时比较特殊，比如映入其他系统的字段，可能都是大写，

可以通过@JsonProperty(value = "HPHM")处理

 /** 车牌号码 */
    @JsonProperty(value = "HPHM")
    private String HPHM;

    /** 车牌颜色 */
    @JsonProperty(value = "HPYS")
    private String HPYS;

    /** 车辆颜色 */
    @JsonProperty(value = "CSYS")
    private String CSYS;

    /** 车辆类型 */
    @JsonProperty(value = "CLLX")
    private Integer CLLX;

3、重写ObjectMapper 对象的 PropertyNamingStrategy方法 列子如下，但是不太建议，会出现不统一的问题，如果有统一规则可以使用。

 final ObjectMapper mapper = new ObjectMapper();
        mapper.setPropertyNamingStrategy(new PropertyNamingStrategy() {  
            private static final long serialVersionUID = 1L;  
            // 反序列化时调用  
            @Override  
            public String nameForSetterMethod(MapperConfig<?> config,  
                    AnnotatedMethod method, String defaultName) {  
                return method.getName().toUpperCase();
            }  
            // 序列化时调用  
            @Override  
            public String nameForGetterMethod(MapperConfig<?> config,  
                    AnnotatedMethod method, String defaultName) {  
                return method.getName().toUpperCase();  
            }  
        });