Re: Java / JSP / MySQL

From:

kuukelekuu@gmail.com

Newsgroups:

comp.lang.java.help

Date:

17 Jan 2007 02:37:22 -0800

Message-ID:

<1169030242.220784.37920@m58g2000cwm.googlegroups.com>

I got it partly to work using this great tutorial, but I'm not able to
do insert querys yet, select and update querys are working fine but
with insert querys I get an exception:

org.apache.jasper.JasperException: Exception in JSP: /index.jsp:21

18: db.connect();
19:
20: try {
21: i = db.insert("INSERT INTO `sessions` (`ip`) VALUES
('127.0.0.1')");
22: out.println(i);
23: }

Java Class:

    public int insert(String sql) throws SQLException {
        Statement s = con.createStatement();
        int res = s.executeUpdate(sql);
        return (res == 0) ? null : res;
    }

    public int update(String sql) throws SQLException {
        Statement s = con.createStatement();
        int res = s.executeUpdate(sql);
        return (res == 0) ? null : res;
    }

Again, the update query works but the insert is not working :s

http://www.roseindia.net/jsp/usingbeansinjsp.shtml

kuukelekuu@gmail.com wrote:

Hi all,

I'm a newbe to Java / JSP and I'm looking into the language. Currently
I'm trying to work with MySQL databases. I have succesfully worked out
this simple code to make sure that a MySQL database connection was
possible with JSP:

<%@ page import="java.sql.*" %>
<%
String connectionURL =
"jdbc:mysql://localhost:3306/mydatabase?user=;password=";
Connection connection = null;
Statement statement = null;
ResultSet rs = null;
%>

<%
Class.forName("com.mysql.jdbc.Driver").newInstance();
connection = DriverManager.getConnection(connectionURL, "", "");
statement = connection.createStatement();
rs = statement.executeQuery("SELECT * FROM mytable");

while (rs.next()) {
out.println(rs.getString("myfield")+"<br>");
}

rs.close();
%>

This workes fine, the next stap for me was finding a logical way of
creating a database connection for a Wizard Application, I assume I
have to create a Connection Object or something, I tryed looking for
that but could not find mutch information about which method to handle
database connections.

My question is, can somewone explain me what the best method is and how
I should do this or point me to a good tutorial about it?

Thanks and regards,

Arno