Creating Rest Service Using Mule ESB 3.3

Creating Rest Services with Mule is very easy as mule provides built in support for Jersey.

Create mule flow in mule studio like this .


create a Rest class like this and link it to rest component :

import javax.ws.rs.Path;
import javax.ws.rs.QueryParam;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.Status;


@Path("restClass")
public class RestClass {

 public Response getExample(@QueryParam("param1")String param1)
 {
  return Response.status(Status.OK).entity("hello " + param1).build();
 }
 
}

This is how the Mule flow xml will look like :

<?xml version="1.0" encoding="UTF-8"?>

<mule xmlns:jersey="http://www.mulesoft.org/schema/mule/jersey" 
xmlns:http="http://www.mulesoft.org/schema/mule/http" 
xmlns="http://www.mulesoft.org/schema/mule/core"
xmlns:doc="http://www.mulesoft.org/schema/mule/documentation" 
xmlns:spring="http://www.springframework.org/schema/beans" version="CE-3.3.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="
http://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd 
http://www.mulesoft.org/schema/mule/jersey http://www.mulesoft.org/schema/mule/jersey/current/mule-jersey.xsd 
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-current.xsd 
http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd ">
    <flow name="restTestFlow1" doc:name="restTestFlow1">
        <http:inbound-endpoint exchange-pattern="request-response" 
host="localhost" port="8081" doc:name="HTTP"/>
        <jersey:resources doc:name="REST">
            <component class="RestClass"/>
         </jersey:resources>
    </flow>
</mule>

If you want to use spring created bean in the rest Component , then first declare the component as spring bean , and then refer it in the jersey-resource using spring-object tag , like this :

<flow name="restTestFlow1" doc:name="restTestFlow1">

     <http:inbound-endpoint exchange-pattern="request-response" host="localhost"
 port="8081" doc:name="HTTP"/>
       <spring:bean id="testBean" class="TestSpringBean"></spring:bean>
    <spring:bean id="restClass">
      <spring:property name="bean" ref="testBean"></spring:property>
    </spring:bean>

        <jersey:resources doc:name="REST">
            <component doc:name="rest component">
             <spring-object bean="restClass">
            </component>
        </jersey:resources>
</flow>

You can use multiple rest classes also , like this :

<jersey:resources doc:name="REST">
   <component>
    <spring-object bean="restService" />
   </component>
   <component>
    <spring-object bean="restService1" />
   </component>
  </jersey:resources>

Mule Studio throws error "Required attribute class is not defined in component" , you can ignore this error, as it runs perfectly fine.

Post your suggestions !!