杰克逊不会将JSON字符串序列化为Java对象
当我尝试使用POST向我的Jersey REST服务传递JSON字符串时,REST客户端返回415 - 不支持的媒体类型。通过GET查询资源工作正常。杰克逊不会将JSON字符串序列化为Java对象
实体类:
@Entity
public class Agent implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
public Agent() {
}
public Agent(String name) {
this.name = name;
}
@OneToMany(mappedBy = "agent", cascade = CascadeType.PERSIST)
@JsonBackReference
private List<Action> actions = new ArrayList<>();
//...getter/setter...
}
服务类REST:
@Path("/agents")
public class AgentService {
private static PersistenceFacade f = new PersistenceFacade();
private static StatusFacade s = new StatusFacade();
//GET all Agents
@GET
@Produces(MediaType.APPLICATION_JSON)
public List<Agent> getAllAgents() {
return f.getAllAgents();
}
@POST
@Path("/create")
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public void postAgent(Agent a) {
f.createAgent(a);
}
}
PersistenceFacade
public class PersistenceFacade {
//EMF als zentraler Handler für alle EM
private static EntityManagerFactory factory = Persistence.createEntityManagerFactory("simulationPU");
public void createAgent(Agent a) {
EntityManager em = factory.createEntityManager();
EntityTransaction tx = em.getTransaction();
tx.begin();
em.persist(a);
tx.commit();
}
public List<Agent> getAllAgents() {
EntityManager em = factory.createEntityManager();
Query q = em.createQuery("SELECT a FROM Agent a");
List<Agent> aList = q.getResultList();
return aList;
}
传递GET请求来http://localhost:8080/simulation_api/agents回报我TESTDATA:
[{"id":2104,"name":"pi3"},{"id":2107,"name":"pi4"}]
但是,当我尝试使用POST将JSON字符串传递到http://localhost:8080/simulation_api/agents/create时,如上所述发生错误(HTTP响应415)。我把要求的身体内:
{"id":2804,"name":"pi7"}
可能是什么问题?没有抛出异常......
@Don波特斯坦 是的,如果我通过卷曲发送POST请求:
curl -X POST -H "Content-Type: application/json" -d {"id":2804
,"name":"pi7"} http://localhost:8080/simulation_api/agents/create -v
然后卷曲的回报:
* Trying ::1...
* Trying 127.0.0.1...
* Connected to localhost (127.0.0.1) port 8080 (#0)
> POST /simulation_api/agents/create HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.45.0
> Accept: */*
> Content-Type: application/json
> Content-Length: 18
>
* upload completely sent off: 18 out of 18 bytes
< HTTP/1.1 500 Request failed.
< Content-Type: text/html;charset=ISO-8859-1
< Date: Sat, 07 Nov 2015 09:26:07 GMT
< Connection: close
< Content-Length: 1033
<
编辑:解
我想通了,有必要通过ObjectMapper类手动将JSON输入字符串转换为对象。 (我认为@Consumes接口做,在后台...)
现在,它的工作原理:
@Path("/agents")
public class AgentService {
private static PersistenceFacade f = new PersistenceFacade();
private static StatusFacade s = new StatusFacade();
//GET all Agents
@GET
@Produces(MediaType.APPLICATION_JSON)
public List<Agent> getAllAgents() {
return f.getAllAgents();
}
@POST
@Path("/create")
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public void postAgent(String content) throws IOException {
ObjectMapper mapper = new ObjectMapper();
Agent a = mapper.readValue(content, Agent.class);
f.createAgent(a);
}
}
这是由于请求中的内容类型不正确引起的,我想。我有同样的问题,我可以看到,在数据包发送领域被打包成一个字符串... http://*.com/questions/43547144/multipart-nodejs-request-with-object-in-it 必须有强制杰克逊自动进行这种转换的方法。 – greengold
你是否包括“内容类型:应用程序/ JSON的”头在你的POST请求? –