Using Jsp in a Jersey JAX-RS RESTful application

Posted: décembre 29th, 2011 | Author: | Filed under: Dev, Glassfish, Java, Java EE, JAX-RS, Jersey, Tools, Tutorial | Tags: , , , , , , , , , , , | 30 Comments »

So, ok we could easily produce some RESTful applications with Jersey.
But sometimes, the output could be very big to put in a method and a template could be useful.

Jersey provides MVC support for JSP pages.
There is a JSP template processor that resolves absolute template references to processable template references that are JSP.


1 – Configure web.xml

<filter>
	<filter-name>jersey</filter-name>
	<filter-class>com.sun.jersey.spi.container.servlet.ServletContainer</filter-class>
	<init-param>
		<param-name>com.sun.jersey.config.property.packages</param-name>
		<param-value>com.ezakus.web</param-value>
	</init-param>
	<init-param>
		<param-name>com.sun.jersey.config.property.JSPTemplatesBasePath</param-name>
		<param-value>/WEB-INF/jsp</param-value>
	</init-param>
	<init-param>
		<param-name>com.sun.jersey.config.property.WebPageContentRegex</param-name>
		<param-value>/(resources|(WEB-INF/jsp))/.*</param-value>
	</init-param>
</filter>
<filter-mapping>
	<filter-name>jersey</filter-name>
	<url-pattern>/*</url-pattern>
</filter-mapping>

Instead of a servlet mapping you need to have a filter.

With the JSPTemplatesBasePath param, you choose your jsp folder

	<param-name>com.sun.jersey.config.property.JSPTemplatesBasePath</param-name>
	<param-value>/WEB-INF/jsp</param-value>

And with the WebPageContentRegex you are able to serve static resources.
In the previous example, static resources are on the /resources/ or /WEB-INF/jsp/ path but you can put what you want :

	<param-name>com.sun.jersey.config.property.WebPageContentRegex</param-name>
	<param-value>/(resources|js|css|images)/.*</param-value>

2 – Return Viewable or Response

Now you can use the Viewable class with your jsp path

package com.ezakus.web;

import javax.ejb.Stateless;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;

import com.sun.jersey.api.view.Viewable;

@Stateless
@Path("/")
public class MyController {

    @GET
    @Produces("text/html")
    public Viewable index() {
    	return new Viewable("/index");
    }

}

Note : /index assume that you have a /WEB-INF/jsp/index.jsp on your path

You can also use the Response class

package com.ezakus.web;

import javax.ejb.Stateless;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.Response;

import com.sun.jersey.api.view.Viewable;

@Stateless
@Path("/")
public class MyController {

    @GET
    @Produces("text/html")
    public Response index() {
    	return Response.ok(new Viewable("/index")).build();
    }

}

3 – Using Viewable’s model

The Viewable object could be created with a model :

package com.ezakus.web;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.ejb.Stateless;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.Response;

import com.sun.jersey.api.view.Viewable;

@Stateless
@Path("/")
public class MyController {

    @GET
    @Produces("text/html")
    public Response index() {
    	Map<String, Object> map = new HashMap<String, Object>();
        map.put("user", "usul");
        List<String> l = new ArrayList<String>();
        l.add("light saber");
        l.add("fremen clothes");
        map.put("items", l);
    	return Response.ok(new Viewable("/cart", map)).build();
    }

}

Note : Jersey will assign the model instance to the attribute « it » in the jsp. (Yes, life is hard)

<%@page contentType="text/html"%>
<%@page pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
   "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
  <title>Welcome!</title>
</head>
<body>
  <h1>Welcome ${it.user}!</h1>
  <p>
  	items in your cart :<br />
    <c:forEach var="item" items="${it.items}">
    	${item}<br />
    </c:forEach>
  </p>
</body>
</html>