I am developing RESTEasy Example. In this example I am using all latest dependencies and deploying om tomcat 8.x version. I can successfully deploy the application but when I am launching the url: http://localhost:8080/RESTfulExample/rest/restwebservice/list, I see following errors are coming. Please guide what is going wrong here.
org.jboss.resteasy.core.NoMessageBodyWriterFoundFailure: Could not find MessageBodyWriter for response object of type: java.util.ArrayList of media type: text/html
at org.jboss.resteasy.core.ServerResponseWriter.writeNomapResponse(ServerResponseWriter.java:66)
at org.jboss.resteasy.core.SynchronousDispatcher.writeResponse(SynchronousDispatcher.java:466)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:415)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:202)
at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:221)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:521)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1096)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:674)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
The code I developed so far for reference: pom.xml
<repositories>
<repository>
<id>JBoss repository</id>
<url>https://repository.jboss.org/nexus/content/groups/public-jboss/</url>
</repository>
</repositories>
<properties>
<java.version>1.8</java.version>
<resteasy-jaxrs-version>3.0.16.Final</resteasy-jaxrs-version>
<junit.version>4.12</junit.version>
</properties>
<dependencies>
<dependency>
<groupId>org.jboss.resteasy</groupId>
<artifactId>resteasy-jaxrs</artifactId>
<version>${resteasy-jaxrs-version}</version>
</dependency>
<dependency>
<groupId>org.jboss.resteasy</groupId>
<artifactId>resteasy-servlet-initializer</artifactId>
<version>${resteasy-jaxrs-version}</version>
</dependency>
<dependency>
<groupId>com.sun.xml.bind</groupId>
<artifactId>jaxb-impl</artifactId>
<version>2.2.11</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
</dependency>
</dependencies>
<!-- Project Build -->
<build>
<finalName>RESTfulExample</finalName>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>${java.version}</source>
<target>${java.version}</target>
</configuration>
</plugin>
</plugins>
</build>
Student.java
@XmlRootElement
public class Student {
private int student_id;
private String student_name;
private String student_rollnumber;
// setters and getters
}
RESTEasyService.java
@ApplicationPath("/rest")
public class RESTEasyService extends Application{
}
RESTWebServiceJavaExample.java
@Path("/restwebservice")
public class RESTWebServiceJavaExample {
private TreeMap<Integer, Student> webserviceMap= new TreeMap<>();
public RESTWebServiceJavaExample(){
Student student = new Student();
student.setStudent_name("Ricky");
student.setStudent_rollnumber("AOHP451");
addStudent(student);
student = new Student();
student.setStudent_name("Mayer");
student.setStudent_rollnumber("DKLP987");
addStudent(student);
}
@GET
@Path("list")
public List<Student> getStudents() {
List<Student> students = new ArrayList<Student>();
students.addAll(webserviceMap.values());
return students;
}
@POST
@Path("add")
@Produces("text/plain")
@Consumes("application/xml")
public void addStudent(Student student_param) {
int id = webserviceMap.size();
student_param.setStudent_id(id);
webserviceMap.put(id, student_param);
}
}
web.xml:
<web-app id="WebApp_ID" version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>Restful Web Application</display-name>
</web-app>
Now I am able to solve this issue. I need to add following dependency in pom.xml:
<dependency>
<groupId>org.jboss.resteasy</groupId>
<artifactId>resteasy-jaxb-provider</artifactId>
<version>3.0.16.Final</version>
</dependency>
And 1) I should be using @Produces(MediaType.APPLICATION_XML) on method signature to get following response.
<collection>
<student>
<student_id>0</student_id>
<student_name>Ricky</student_name>
<student_rollnumber>AOHP451</student_rollnumber>
</student>
<student>
<student_id>1</student_id>
<student_name>Mayer</student_name>
<student_rollnumber>DKLP987</student_rollnumber>
</student>
</collection>
If you want to use @Produces(MediaType.TEXT_PLAIN) then code will gives you following output which doesn't looks useful.
[com.mkyong.rest.Student@4d5fd75e, com.mkyong.rest.Student@7715574d]
So use 1) solution.