Pertemuan 11 Aplikasi Web dengan Servlet dan JSP Matakuliah : T0053/Web Programming
Matakuliah
Tahun
Versi
: T0053/Web Programming
: 2006
: 2
Pertemuan 11
Aplikasi Web dengan Servlet dan JSP
1
Learning Outcomes
Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu :
• Menjelaskan Teknik membangun aplikasi web berbasis Servlet dan JSP yang terhubung ke database
• Membuat aplikasi web yang lebih komplek menggunakan Servlet dan JSP yang terkoneksi ke database
• Menggunakan session & cookie
2
Outline Materi
• Aplikasi web dengan Servlet dan JSP
• Aplikasi web menggunakan JDBC tingkat lanjut
3
Advanced Servlet
4
Codes
<TITLE>Guest Book Form www.widodo.com</TITLE>
</HEAD>
<BODY bgcolor=silver>
<font color=blue> <H1 align =center>Guest Book
Binus</H1></font>
<hr>
<FORM ACTION=http://localhost:8084/WebJ2EE
/GuestBookServlet
METHOD=POST> <PRE>
Email address: <INPUT TYPE=text NAME=Email>
First Name: <INPUT TYPE=text NAME=FirstName>
….
5
Servlet import java.io.*;import javax.servlet.*;import javax.servlet.http.*; import java.util.*;import java.sql.*; public class GuestBookServlet extends HttpServlet { private Statement statement = null; private Connection connection = null; private String URL = "jdbc:odbc:Kopi"; public void init( ServletConfig config )throws ServletException
{ super.init( config ); try {
Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" ); connection = DriverManager.getConnection( URL, "sa", "" );
} catch ( Exception e ) { e.printStackTrace();connection = null;
}} public void doPost( HttpServletRequest req,HttpServletResponse res )
{ throws ServletException, IOException
String email, firstName, lastName, company,
….
6
Servlet public void doPost( HttpServletRequest req,HttpServletResponse res )
{ throws ServletException, IOException
String email, firstName, lastName, company, snailmailList, cppList, javaList, vbList, iwwwList; email = req.getParameter( "Email" ); firstName = req.getParameter( "FirstName" ); lastName = req.getParameter( "LastName" ); company = req.getParameter( "Company" ); snailmailList = req.getParameter( "mail" ); cppList = req.getParameter( "c_cpp" ); javaList = req.getParameter( "java" ); vbList = req.getParameter( "vb" ); iwwwList = req.getParameter( "iwww" );
PrintWriter output = res.getWriter();
…..
res.setContentType( "text/html" );
7
Codes private boolean insertIntoDB( String stringtoinsert )
{ try { statement = connection.createStatement(); statement.execute(
"INSERT INTO GuestBook values (" + stringtoinsert + ");" ); statement.close();
} catch ( Exception e ) {
System.err.println(
"ERROR: bermasalah menambahkan data baru" ); e.printStackTrace(); return false;
} return true;
} public void destroy()
{ catch( Exception e ) {
System.err.println( "bermasalah menutup database" );
}
} try { connection.close();
}}
8
Sample Web
9
Display Data
<font color=blue><h1>Daftar Programmer</h1></font>
<table border="1" cellpading="5" cellspacing="0" bgcolor=silver bordercolor=green>
<tr><td>No</td><td>nama</td><td>
Deskripsi</td><td>Aksi</td></tr>
<%@ page import="java.sql.*"%>
<%
Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con = DriverManager.getConnection
("jdbc:odbc:kopi","sa",“password");
Statement stmt = con.createStatement ();
ResultSet rst = stmt.executeQuery ("Select * from programmer");
10
Display Data
{ while(rst.next()) //baca data int no=rst.getInt("no");
String nama=rst.getString("nama");
String deskripsi=rst.getString("deskripsi"); out.print ("<tr><td>"+no+"</td>"); out.print ("<td>"+nama+"</td>"); out.print ("<td>"+deskripsi+"</td>"); out.print ("<td><a href=rubahdb.jsp?" + no + ">Rubah Data"); out.print ("<a> | <a href =hapusdb.jsp?" + no + ">Hapus
Data</a>");
} out.println ("</td></tr>"); stmt.close(); con.close();
11
Add Data
12
Add Data
<%@ page import="java.sql.*" %>
<%
String nama=request.getParameter ("nama");
String ganti=request.getParameter ("TextGanti");
String sql="insert into programmer (nama,deskripsi) " +
"values"('"+ nama + "','" + ganti+ "')";
Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con = DriverManager.getConnection
("jdbc:odbc:kopi","sa","mautauaja");
Statement stmt = con.createStatement (); stmt.executeUpdate(sql); stmt.close(); con.close();
%>
<jsp:forward page="programmer.jsp"/>
13
Edit Data
14
Edit Data
String kunci=request.getQueryString();
String sql= "Select * from programmer where programmer.no = " + kunci;
Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con = DriverManager.getConnection
("jdbc:odbc:Trisakti","sa",“password");
Statement stmt = con.createStatement ();
ResultSet rs=stmt.executeQuery(sql); rs.next();
%>
<form method="POST" action="simpandb.jsp">
<% out.println ("<h3> Silahkan Update data </h3><br>");%>
<textarea rows="5" name="nama" cols="22">
<%= rs.getString ("nama") %>
</textarea>
15
Save Data
<%@ page import="java.sql.*" %>
<%
String kunci=request.getParameter ("kunci");
String nama=request.getParameter("nama");
String ganti=request.getParameter ("TextGanti");
String sql ="update programmer set nama='" + nama + "', deskripsi='" + ganti+"' where no="+ kunci;
Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con = DriverManager.getConnection
("jdbc:odbc:Trisakti","","");
Statement stmt = con.createStatement (); stmt.executeUpdate(sql); stmt.close(); con.close();
%>
<jsp:forward page="programmer.jsp"/>
16
Session & Cookie
When you are working with an application, you open it, do some changes and then you close it. This is much like a Session. The computer knows who you are. It knows when you start the application and when you end.
But on the internet there is one problem: the web server does not know who you are and what you do because the HTTP address doesn't maintain state.
Java solves this problem by creating a unique cookie for each user. The cookie is sent to the client and it contains information that identifies the user. This interface is called the Session object.
17
Cookie
//buat session session.setAttribute("idk", idk);
//baca session
String idk=(String)session.getAttribute("idk");
Cookie[] cookies = request.getCookies(); for (int i = 0; i < cookies.length; i++) {
Cookie c = cookies[i];
String name = c.getName();
String value = c.getValue(); out.println(name + " = " + value);
18
References
Deithel, “Java How To Program”, 5 th ed,
2006
Widodo Budiharto, “Panduan Lengkap
Pemrograman J2EE”, Andi Offset
Yogyakarta, 2006
www.apache.org
www.w3schools.com
www.struts.org
www.netbeans.org
19
