JSON响应:
{
"categories": [{
"id": "1",
"category": "category1"
},
{
"id": "2",
"category": "category2"
}
]
}
JSON 泽西服务:
@GET
@Produces("application/json")
public List<Categories> GetAllCategories() {
return CategoriesDAO.getInstance().getAll();
}
我使用 EJB 注释进行休眠映射,使用 jaxB 进行反序列化和序列化 JSON。
模型:
@Entity
@XmlRootElement
public class Categories {
/** @pdOid f9032734-7d05-4867-8275-bf10813c3748 */
@Id
@GeneratedValue
private Integer id;
private String category;
public Categories() {
// TODO Add your own initialization code here.
}
public Integer getId() {
return id;
}
public void setId(Integer newId) {
this.id = newId;
}
public String getCategory() {
return category;
}
public void setCategory(String newCategory) {
this.category = newCategory;
}
}
泽西客户端代码:
ClientConfig clientConfig = new DefaultClientConfig();
clientConfig.getFeatures().put(JSONConfiguration.FEATURE_POJO_MAPPING, Boolean.TRUE);
Client client = Client.create(clientConfig);
WebResource r = client.resource("http://tomcat.com/GetAllCategories");
List<Categories> output = r.get(new GenericType<List<Categories>>() {});
例外:
Exception in thread "main" com.sun.jersey.api.client.ClientHandlerException: org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of java.util.ArrayList out of START_OBJECT token
at [Source: sun.net.www.protocol.http.HttpURLConnection$HttpInputStream@cc4364; line: 1, column: 1]
at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:564)
at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:524)
at com.sun.jersey.api.client.WebResource.handle(WebResource.java:696)
at com.sun.jersey.api.client.WebResource.get(WebResource.java:196)
at com.fit.test.Json.GetAllKategorijeJson.main(GetAllKategorijeJson.java:34)
Caused by: org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of java.util.ArrayList out of START_OBJECT token
at [Source: sun.net.www.protocol.http.HttpURLConnection$HttpInputStream@cc4364; line: 1, column: 1]
at org.codehaus.jackson.map.JsonMappingException.from(JsonMappingException.java:163)
at org.codehaus.jackson.map.deser.StdDeserializationContext.mappingException(StdDeserializationContext.java:219)
at org.codehaus.jackson.map.deser.StdDeserializationContext.mappingException(StdDeserializationContext.java:212)
at org.codehaus.jackson.map.deser.std.CollectionDeserializer.handleNonArray(CollectionDeserializer.java:246)
at org.codehaus.jackson.map.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:204)
at org.codehaus.jackson.map.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:194)
at org.codehaus.jackson.map.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:30)
at org.codehaus.jackson.map.ObjectMapper._readValue(ObjectMapper.java:2695)
at org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1308)
at org.codehaus.jackson.jaxrs.JacksonJsonProvider.readFrom(JacksonJsonProvider.java:419)
at com.sun.jersey.json.impl.provider.entity.JacksonProviderProxy.readFrom(JacksonProviderProxy.java:139)
at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:554)
... 4 more