我已经读过,我可以创建javax.ws.rs.ext.ExceptionMapper
的实现,它将抛出的应用程序异常映射到Response
对象。
我创建了一个简单的示例,如果持久化对象时手机长度超过20个字符,则抛出异常。我期望将异常映射到HTTP 400(错误请求)响应;但是,我收到HTTP 500(内部服务器错误),但有以下异常:
java.lang.ClassCastException: com.example.exception.InvalidDataException cannot be cast to java.lang.Error
我错过了什么?非常感谢任何建议。
异常映射器:
@Provider
public class InvalidDataMapper implements ExceptionMapper<InvalidDataException> {
@Override
public Response toResponse(InvalidDataException arg0) {
return Response.status(Response.Status.BAD_REQUEST).build();
}
}
异常类:
public class InvalidDataException extends Exception {
private static final long serialVersionUID = 1L;
public InvalidDataException(String message) {
super(message);
}
...
}
实体类:
@Entity
@Table(name="PERSON")
@XmlAccessorType(XmlAccessType.FIELD)
@XmlRootElement
public class Person {
@Id @GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name="ID")
private Long id;
@Column(name="NAME")
private String name;
@Column(name="PHONE")
private String phone;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
@PrePersist
public void validate() throws InvalidDataException {
if (phone != null) {
if (phone.length() > 20) {
throw new InvalidDataException("Phone number too long: " + phone);
}
}
}
}
服务:
@Path("persons/")
@Produces(MediaType.APPLICATION_XML)
@Consumes(MediaType.APPLICATION_XML)
@Stateless
public class PersonResource {
@Context
private UriInfo uriInfo;
@PersistenceContext(name="simple")
private EntityManager em;
@POST
public Response createPerson(JAXBElement<Person> personJaxb) {
Person person = personJaxb.getValue();
em.persist(person);
em.flush();
URI personUri = uriInfo.getAbsolutePathBuilder().
path(person.getId().toString()).build();
return Response.created(personUri).build();
}
}
答案 0 :(得分:31)
是否将InvalidDataException包装在PersistenceException中?也许你可以做类似以下的事情:
@Provider
public class PersistenceMapper implements ExceptionMapper<PersistenceException> {
@Override
public Response toResponse(PersistenceException arg0) {
if(arg0.getCause() instanceof InvalidDataException) {
return Response.status(Response.Status.BAD_REQUEST).build();
} else {
...
}
}
}
答案 1 :(得分:-2)
交叉检查你的web.xml你需要注册你的“PersistenceMapper”课程以及服务。