Java EE6 - POJO injection

Simplest Possible POJO Injection Example With Java EE 6
http://www.adam-bien.com/roller/abien/entry/simplest_possible_pojo_injection_example

Annotation Type Inject

http://download.oracle.com/javaee/6/api/javax/inject/Inject.html


Contexts and Dependency Injection for the Java EE Platform

http://www.oracle.com/technetwork/articles/javaee/javaee6overview-141808.html#webbeans


TestInject class

package testinject;

import javax.ejb.EJB;
import javax.inject.Named;

import testejb.BackendBeanLocal;
import testservice.MasterDataCacheLocal;

@Named("TestInject")
public class TestInject {
    
    
    public TestInject(){
        System.out.println("TestInject : constructor");
    }

    @EJB
    MasterDataCacheLocal masterDataCache;
    
    @EJB
    BackendBeanLocal service;
    
    public void callService(){
        
        if(masterDataCache.get("dave") == null){
            masterDataCache.store("dave","dave");
        }
        
        System.out.println("TestInject: callService" );
        service.runService();
        
    }

}

Inject POJO in Test Servlet

  @Inject
    TestInject testInject;

protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
        
        out.println("testInject.callService()<br>");
        testInject.callService();

This file is necessary to force to injection
/testWEB/WebContent/WEB-INF/beans.xml
http://download.oracle.com/javaee/6/tutorial/doc/gjbnz.html

</beans>

TestServlet

package testWEB;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;

import javax.ejb.EJB;
import javax.inject.Inject;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import testinject.TestInject;
import testservice.TestServiceLocal;

/**
 * Servlet implementation class TestServlet
 */
@WebServlet("/TestServlet")
public class TestServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public TestServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

    @EJB TestServiceLocal service;
    
    @Inject
    TestInject testInject;
    
    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
        PrintWriter out = res.getWriter();
        res.setContentType("text/html");
        
        HttpSession session = req.getSession(true);

        String heading;
        Integer accessCount = new Integer(0);
        if (session.isNew()) {
            heading = "Welcome, Newcomer";
        } else {
            heading = "Welcome Back";
            Integer oldAccessCount = (Integer) session
                    .getAttribute("accessCount");
            if (oldAccessCount != null) {
                accessCount = new Integer(oldAccessCount.intValue() + 1);
            }
        }
        session.setAttribute("accessCount", accessCount);
        
        out.println("service.callService()<br>");
        service.callService();
        
        out.println("testInject.callService()<br>");
        testInject.callService();

        out.println("<H1>This is a password protected resource</H1>");
        out.println("<PRE>");
        out.println("User Name: " + req.getRemoteUser());
        String name = (req.getUserPrincipal() == null) ? null : req
                .getUserPrincipal().getName();
        out.println("Principal Name: " + name);
        out.println("Authentication Type: " + req.getAuthType());
        out.println("Is a Manager: " + req.isUserInRole("AppRole"));
        out.println("</PRE>");
        out.println(
                "<H1 ALIGN=\"CENTER\">" + heading + "</H1>\n" +
                "<H2>Update Servlet!!! Information on Your Session:</H2>\n" +
                "<TABLE BORDER=1 ALIGN=CENTER>\n" +
                "<TR BGCOLOR=\"#FFAD70\">\n" +
                "  <TH>Info Type<TH>Value\n" +
                "<TR>\n" +
                "  <TD>ID\n" +
                "  <TD>" + session.getId() + "\n" +
                "<TR>\n" +
                "  <TD>Creation Time is\n" +
                "  <TD>" + new Date(session.getCreationTime()) + "\n" +
                "<TR>\n" +
                "  <TD>Time of Last Access\n" +
                "  <TD>" + new Date(session.getLastAccessedTime()) + "\n" +
                "<TR>\n" +
                "  <TD>Number of Previous Accesses\n" +
                "  <TD>" + accessCount + "\n" +
                "</TABLE>\n");
        out.println("</BODY></HTML>");
        
        
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
    }

}

Application Server log

[#|2011-11-06T22:49:45.979+0100|INFO|glassfish3.1.1|javax.enterprise.system.container.web.com.sun.enterprise.web|_ThreadID=17;_ThreadName=Thread-2;|WEB0671: Loading application [testEAR#testWEB.war] at [testWEB]|#]

[#|2011-11-06T22:49:46.002+0100|INFO|glassfish3.1.1|javax.enterprise.system.tools.admin.org.glassfish.deployment.admin|_ThreadID=17;_ThreadName=Thread-2;|testEAR was successfully deployed in 911 milliseconds.|#]

[#|2011-11-06T22:50:30.394+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|TestInject : constructor|#]

[#|2011-11-06T22:50:30.401+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|principal=dave|#]

[#|2011-11-06T22:50:30.404+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|MasterDataCache.initCache|#]

[#|2011-11-06T22:50:30.409+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|MasterDataCache.get dave|#]

[#|2011-11-06T22:50:30.411+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|TestService: masterDataCache.store|#]

[#|2011-11-06T22:50:30.413+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|MasterDataCache.store dave|#]

[#|2011-11-06T22:50:30.413+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|TestService: callService|#]

[#|2011-11-06T22:50:30.415+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|BackendBean: runService|#]

[#|2011-11-06T22:50:30.417+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|MasterDataCache.get dave|#]

[#|2011-11-06T22:50:30.417+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|TestInject: callService|#]

[#|2011-11-06T22:50:30.418+0100|INFO|glassfish3.1.1|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=24;_ThreadName=Thread-2;|BackendBean: runService|#]