// guestbook6.java
//
// by Jeff Schmitt
// Towson University
// September, 1998
//
// based on guestbook3.java
// http://triton.towson.edu/~schmitt/java/jdbc/guestbook3.html
// and converted from CGI to servlet technology
// You need to import the java.sql package to use JDBC
import java.sql.*; /* Java 1.1 */
import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
/**
* guestbook6 servlet. This servlet uses JDBC to access and append
* guestbook entries into the database.
*
* @version 1.0, 09/30/98
* @author Jeff Schmitt
*/
public class guestbook6 extends HttpServlet {
/**
* Handles a single guestbook request from the client.
*/
public void doGet (HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
String name = req.getParameter("NAME");
String aff1 = req.getParameter("AFF1");
String aff2 = req.getParameter("AFF2");
String email = req.getParameter("EMAIL");
// the submit button for View Guestbook
String view = req.getParameter("view");
res.setContentType("text/html");
ServletOutputStream out = res.getOutputStream();
out.println("Guestbook 6");
out.println("
Guestbook6
");
out.println("
Java Servlet using JDBC
");
// Load the GWE Mysql JDBC driver
try {
Class.forName ("gwe.sql.gweMysqlDriver");
} catch (Exception e) {
out.println("write to log: Error in program");
}
out.println("
Hello "+req.getRemoteHost()+"
");
// Read the MySQL userid and password from the datafile
// .mysql-init in your home directory
String account="**";
String password="**";
try {
BufferedReader in = new BufferedReader(new InputStreamReader(
new FileInputStream("/usr/faculty/schmitt/.mysql-init")));
account=in.readLine();
password=in.readLine();
} catch (Exception e) {
out.println("guestbook6: cannot read .mysql-init");
System.exit(1);
}
// Connect to the database
// if the connection parameters are wrong you will get the
// error message "No suitable driver" -- check the documentation
// for the jdbc driver you are using.
// For the GWE mysql implementation of JDBC, it
// looks for connection URL's in the form of
// jdbc:mysql://[host_addr]:[port]/[db_name]
// jdbc:mysql:db_name
try {
Connection conn = DriverManager.getConnection
("jdbc:mysql://:3306/schmitt", account, password);
Statement stmt = conn.createStatement ();
ResultSet rset=null;
if (view == null && (name!=null || aff1!=null ||
aff2!=null || email!=null) ) {
// insert the form values into the guestbook
try {
// Insert the guestbook data into table guestbook6
rset = stmt.executeQuery("insert into guestbook6 values ('"+
name+"', '"+aff1+"', '"+aff2+"','"+email+"')");
} catch (SQLException e) {
// the above insert raises the exception:
// java.sql.SQLException: mysql exception: No columns returned.
// -- this should be investigated further
// for now we will ignore it
// out.println("writetolog: Error in insert"+e+" ");
}
}
// Select all columns from the table guestbook6
rset = stmt.executeQuery ("select * from guestbook6");
// Iterate through the result and print the Guestbook
out.println("