JAX-RS JAXB JSON响应不起作用（MessageBodyProviderNotFoundException）

Question

我一直在努力了一段找出如何创建一个JAX RESTful服务......利用现有的指南在这里- 新泽西

如2.3.2节所述，我在Maven中添加了以下依赖项-

<dependency>
    <groupId>org.glassfish.jersey.containers</groupId>
    <artifactId>jersey-container-servlet</artifactId>
    <version>2.0</version>
</dependency>

在web.xml中

<servlet>
    <servlet-name>Jersey REST Service</servlet-name>
    <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
    <init-param>
        <param-name>jersey.config.server.provider.classnames</param-name>
        <param-value>org.glassfish.jersey.filter.LoggingFilter</param-value>
    </init-param>
    <init-param>
        <param-name>javax.ws.rs.Application</param-name>
        <param-value>com.hms.rs.controller.MyApp</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>

  <servlet-mapping>
    <servlet-name>Jersey REST Service</servlet-name>
    <url-pattern>/services/*</url-pattern>
  </servlet-mapping>

和MyApp.java

public class MyApp extends Application{

     @Override
        public Set<Class<?>> getClasses() {
            return new HashSet<Class<?>>() {{
                // Add your resources.
            System.out.println("From the Myapp...");
                add(Patient.class);
                add(PatientController.class);

            // Add LoggingFilter.
                add(LoggingFilter.class);
            }};
        }
}

Patient.java-

@XmlRootElement(name = "Patient")
public class Patient {

    private String patientFName;
    private String patientLName;
    private int patientAge;
    private String patientSex;
    private String patientParentSpouse;
    private String patientQual;
    private String patientOccupation;
    private String patientComments;

    public Patient()
    {
    }

Setters and Getters....

}

PatientController.java-

@Path("/ManagePatient")
public class PatientController {
      @GET
  @Path("/getPatient")
  @Produces(MediaType.APPLICATION_XML)
  public Patient printPatient() {
      System.out.println("Hello.... from the PatientController");
      Patient ptnt = new Patient();
      ptnt.setPatientFName("FirstN");
      ptnt.setPatientLName("LName");
      ptnt.setPatientAge(30);
      ptnt.setPatientSex("M");
      ptnt.setPatientParentSpouse("ParentSpuse");
      ptnt.setPatientQual("engg");
      ptnt.setPatientOccupation("software");
      ptnt.setPatientComments("comments here");

      System.out.println("Patient = " + ptnt);

    //return ptnt.toString();
      return ptnt;
  } 

当我尝试通过浏览器@ localhost：8080 / HMS_Web / services / ManagePatient / getPatient访问此文件时

我正进入（状态

javax.servlet.ServletException: org.glassfish.jersey.message.internal.MessageBodyProviderNotFoundException: MessageBodyWriter not found for media type=text/html, type=class com.hms.app.ui.beans.Patient, genericType=class com.hms.app.ui.beans.Patient.

而且我还在日志中看到以下警告-

WARNING: A provider com.hms.app.ui.beans.Patient registered in SERVER runtime does not implement any provider interfaces applicable in the SERVER runtime. Due to constraint configuration problems the provider com.hms.app.ui.beans.Patient will be ignored. 

如果Jersey 2.0支持Jersey指南中“ 8.1.1.2。基于JAXB的JSON支持”一节中提到的基于JAXB的xml或json支持，我不确定为什么会收到Provider错误。

任何JAX-WS专家都可以帮助我理解并提供有关如何解决这种情况的指导吗？

先感谢您

Answer 1

您正在通过浏览器访问该服务，因此您的PatientController将尝试将响应呈现为html，我想这就是

javax.servlet.ServletException: org.glassfish.jersey.message.internal.MessageBodyProviderNotFoundException: MessageBodyWriter not found for media type=text/html, type=class com.hms.app.ui.beans.Patient, genericType=class com.hms.app.ui.beans.Patient.

尝试通过jersey客户端api使用服务，如下所示：

WebTarget webTarget = client.target("http://localhost:8080/HMS_Web/services/ManagePatient/getPatient");

Patient patient = webTarget.request(MediaType.APPLICATION_XML_TYPE).get(Patient.class);

警告：

WARNING: A provider com.hms.app.ui.beans.Patient registered in SERVER runtime does not implement any provider interfaces applicable in the SERVER runtime. Due to constraint configuration problems the provider com.hms.app.ui.beans.Patient will be ignored. 

我认为您应该删除：

add(Patient.class);

在您的MyApp中 。 患者只是一个POJO，它既不是资源也不是提供者。