Fahad Mullaji Fahad Mullaji - 1 month ago 6
Java Question

MessageBodyWriter not found for media type=application/json

I am facing issues while consuming JAX-RS services as JSON.

Below I have added my code.

This is my service class:

//Sets the path to base URL + /hello
@Path("/hello")
@Consumes(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_JSON)
public class Hello {

@GET
@Produces("application/json")
public Student getStudent() {

Student s = new Student();
s.first_name = "Test First Name !!!";
s.last_name = "Test Last Name!!!";

return s;
}


Student
class which I am trying to get from service:

@XmlRootElement
public class Student implements Serializable {

public String first_name;
public String last_name;

public String getFirst_name() {
return first_name;
}

public void setFirst_name(String first_name) {
this.first_name = first_name;
}

public String getLast_name() {
return last_name;
}

public void setLast_name(String last_name) {
this.last_name = last_name;
}

public Student()
{
first_name = "Fahad";
last_name = "Mullaji";
}
}


Web XML on service side.

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
id="WebApp_ID" version="3.0">
<display-name>com.vogella.jersey.first</display-name>
<servlet>
<servlet-name>Jersey REST Service</servlet-name>
<servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
<!-- Register resources and providers under com.vogella.jersey.first package. -->
<init-param>
<param-name>jersey.config.server.provider.packages</param-name>
<param-value>com.vogella.jersey.first</param-value>
</init-param>
<init-param>
<param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
<param-value>true</param-value>
</init-param>

<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Jersey REST Service</servlet-name>
<url-pattern>/rest/*</url-pattern>
</servlet-mapping>
</web-app>


I don't know how to fix this issue.
I am using SOAP UI for testing JSON response but I guess that it should not matter.

Many places I read that I need to add the code below. But I don't know where. I am not using Maven for building.

<dependency>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-moxy</artifactId>
</dependency>


Server is looking for function to parse
Student
object to JSON but it is not able to find function or jar file for it.
I have added jar of Genson, Moxy, RESTEasy and Jackson but I think that's the problem.
I think I am missing mapping somewhere.

Answer

Well, I could not make the above web project working. But I kept on doing research on JAX-RS and I came across Stormpath's tutorial. I think whoever is trying to learn how REST, JSON and Jersey work together should watch this.

Please see links below for their presentation and sample REST project on GitHub .

https://www.youtube.com/watch?v=sVvL12BnIyQ

https://github.com/stormpath/todos-jersey

Now I can compare above project and see what all things I did wrong.