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Java > Open Source Codes > example > cmp > id > ClientServlet


1 package example.cmp.id;
2
3 import javax.servlet.*;
4 import javax.servlet.http.*;
5
6 import javax.ejb.*;
7
8 import javax.naming.*;
9
10 import java.util.Collection;
11 import java.util.Iterator;
12
13 import java.io.PrintWriter;
14
15 /**
16  * A client to illustrate EJB managed identifying relationships.
17  */
18 public class ClientServlet extends HttpServlet {
19   StudentHome _studentHome = null;
20   QuidditchHome _quidditchHome = null;
21
22   /**
23    * Sets the student ejb local home.
24    */
25   public void setStudentHome(StudentHome home)
26   {
27     _studentHome = home;
28   }
29
30   /**
31    * Sets the quidditch ejb local home.
32    */
33   public void setQuidditchHome(QuidditchHome home)
34   {
35     _quidditchHome = home;
36   }
37
38   /**
39    * Load the EJB Home objects one.
40    */
41   public void init()
42     throws ServletException
43   {
44     try {
45       Context ic = new InitialContext();
46       Context cmp = (Context) ic.lookup("java:comp/env/cmp");
47
48       // get the Student CMP-Bean home interface
49 if (_studentHome == null)
50         _studentHome = (StudentHome) cmp.lookup("id_StudentBean");
51
52       // get the House CMP-Bean home interface
53 if (_quidditchHome == null)
54         _quidditchHome = (QuidditchHome) cmp.lookup("id_QuidditchBean");
55     } catch (NamingException e) {
56       throw new ServletException(e);
57     }
58   }
59
60   /**
61    * Print the statistics for all the students.
62    */
63   public void service(HttpServletRequest req, HttpServletResponse res)
64     throws java.io.IOException, ServletException
65   {
66     res.setContentType("text/html");
67
68     PrintWriter out = res.getWriter();
69
70     // for all students, print in which House they live
71 Collection students = null;
72     try {
73       students = _studentHome.findAll();
74     } catch(javax.ejb.FinderException e) {
75       throw new ServletException(e);
76     }
77
78     out.println("<h3>Student Quidditch statistics</h3>");
79
80     out.println("<table>");
81     out.println("<tr><th>Student<th>Position<th>Points");
82
83     Iterator iter = students.iterator();
84     while (iter.hasNext()) {
85       Student student = (Student) iter.next();
86
87       out.print("<tr><td>" + student.getName());
88       
89       Quidditch quidditch = student.getQuidditch();
90
91       if (quidditch != null) {
92         out.print("<td>" + quidditch.getPosition());
93         out.println("<td>" + quidditch.getPoints());
94       }
95       else {
96         out.println("<td>none<td>n/a");
97       }
98     }
99
100     out.println("</table>");
101   }
102 }
103
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