001 <!-- ----------------------------------------------------------------------- -->
002 <!-- MDB sample page -->
003 <!-- ----------------------------------------------------------------------- -->
004 <HTML>
005 <HEAD>
006 <%@ page import="examples.ejb.ejb30.domain.Book,
007 examples.ejb.ejb30.domain.Review,
008 examples.ejb.ejb30.domain.Reviewer,
009 examples.ejb.ejb30.service.ReviewService,
010 javax.naming.Context,
011 javax.naming.InitialContext"
012 errorPage="exception.jsp" %>
013 <%@ page import="java.util.List" %>
014 <%@ page import="java.util.Random" %>
015 <%@ page import="examples.ejb.ejb30.web.Constants"%> <link href="sample.css" rel="stylesheet">
016 </HEAD>
017
018 <BODY>
019 <%@ include file="header.html" %>
020
021 <%
022 String SERVICE_NAME = "ReviewManagerBean";
023 ReviewService service = (ReviewService) session.getAttribute(SERVICE_NAME);
024 if (service == null) {
025 Context ctx = new InitialContext();
026 service = (ReviewService) ctx.lookup("java:comp/env/ejb/ReviewManager");
027 session.setAttribute(SERVICE_NAME, service);
028 }
029 %>
030
031
032 <HR>
033
034
035 <%
036 java.util.Random random = new Random(System.currentTimeMillis());
037 // randomly select a book.
038 List<Book> books = service.getAll(Book.class);
039 if (books == null || books.isEmpty()) {
040 out.println("Found no book in the database");
041 return;
042 }
043 Book book = books.get(random.nextInt(books.size()));
044
045 //randomly select a subscriber for the current session.
046 List<Reviewer> reviewers = service.getAll(Reviewer.class);
047 if (reviewers == null || reviewers.isEmpty()) {
048 out.println("Found no book in the database");
049 return;
050 }
051 String watcherName = (String) session.getAttribute("watcher");
052 Reviewer watcher = null;
053 if (watcherName == null) {
054 watcher = reviewers.get(random.nextInt(reviewers.size()));
055 session.setAttribute("watcher", watcher.getName());
056 } else {
057 watcher = service.getReviewer(watcherName,false);
058 }
059
060 //randomly select a reviewer differnt from the subscriber.
061 int index = random.nextInt(reviewers.size());
062 Reviewer reviewer = reviewers.get(index);
063 if(reviewer.getName().equals(watcherName)){
064 reviewer = reviewers.get((index+1)/reviewers.size());
065 }
066
067 //let the subscriber watchs new reivews on the given item.
068 service.subscribe(watcher.getName(), book.getId());
069 //let the review make a review on the same book.
070 Review newReview = service.newReview(reviewer, book, 3, "it's a good book ( a review only for testing made by "+reviewer.getName()+" ).");
071
072
073 Thread.sleep(1000 * 10);
074 List<Review> myReviews = service.getFeededReviews(watcher.getName());
075 %>
076 <p>
077
078 This example demonstrates the simplied Message Driven Bean programming model in EJB3.0.<BR/> <BR/>
079 A randomly selected reviewer '<%=watcher.getName()%>' first subsribes new reviews on a randomly selectd book '<%=book.getTitle()%>';
080 Another randomly reviewer <%=reviewer.getName()%> adds a review on the selected book '<%=book.getTitle()%>'.<BR/><BR/>
081 ReviewerManagerBean persists the Review into database and sends a JMS message carrying the review id into JMS queue.<BR/><BR/>
082 The <a href="<%=Constants.JAVA_SOURCE_BASE_DIR%>/mdb/WatchProcessMDB.html">WatchProcessMDB</a> feeds the newly added reviews into all subscribers of '<%=book.getTitle()%>'. <BR/><BR/>
083 Then all <%=watcher.getName()%>'s feeds is listed below.The new feed is highlighted. <BR/>
084 <HR>
085 <CENTER>
086 <BR>
087
088 <TABLE id="feeds-table" CELLPADDING="2" CELLSPACING="2" WIDTH="100%">
089 <TR>
090 <TH ALIGN="LEFT" WIDTH="20%">Reviwer</TH>
091 <TH ALIGN="LEFT" WIDTH="25%">Title</TH>
092 <TH ALIGN="LEFT" WIDTH="15%">Score</TH>
093 <TH ALIGN="LEFT" WIDTH="40%">Comments</TH>
094 </TR>
095
096 <%
097 int k = 0;
098 for (Review myRev : myReviews) {
099 StringBuffer sb = new StringBuffer();
100 String style = (k++%2==0) ? "spec" : "specalt";
101 if(myRev.getId()==newReview.getId()) {
102 style = "highlighted";
103 }
104 sb.append("<TR CLASS='").append(style).append("'><TD>").append(myRev.getReviewer().getName());
105 sb.append("</TD><TD>").append(myRev.getReviewed().getTitle());
106 sb.append("</TD><TD ALIGN='RIGHT'>").append(myRev.getRating());
107 sb.append("</TD><TD>").append(myRev.getComment()).append("</TD></TR>");
108 out.println(sb);
109 }
110 %>
111
112 </TABLE>
113
114 </CENTER>
115 </BODY>
116 </HTML>
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