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**bd30**

Hey all, I'm trying to run a simple JavaBean from a JSP page that displays a table from a mySQL database. I keep getting an error that reads:

HTTP Status 500 -

--------------------------------------------------------------------------------

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: Unable to compile class for JSP

An error occurred at line: 6 in the jsp file: /Select.jsp

Generated servlet error:
[javac] Compiling 1 source file

C:\jakarta-tomcat-4.1.18-LE-jdk14\work\Standalone\localhost\_\Select_jsp.java:48: cannot resolve symbol
symbol : class DataBaseSelect
location: class org.apache.jsp.Select_jsp
DataBaseSelect select = null;
^

An error occurred at line: 6 in the jsp file: /Select.jsp

Generated servlet error:
C:\jakarta-tomcat-4.1.18-LE-jdk14\work\Standalone\localhost\_\Select_jsp.java:50: cannot resolve symbol
symbol : class DataBaseSelect
location: class org.apache.jsp.Select_jsp
select = (DataBaseSelect) pageContext.getAttribute("select", PageContext.REQUEST_SCOPE);
^

An error occurred at line: 6 in the jsp file: /Select.jsp

Generated servlet error:
C:\jakarta-tomcat-4.1.18-LE-jdk14\work\Standalone\localhost\_\Select_jsp.java:53: cannot resolve symbol
symbol : class DataBaseSelect
location: class org.apache.jsp.Select_jsp
select = (DataBaseSelect) java.beans.Beans.instantiate(this.getClass().getClassLoader(), "DataBaseSelect");
^
3 errors

I'm not sure exactly what to do - I have placed DataBaseSelect.class in nearly every subdirectory, but nothing works. The code for the JSP and Bean is below:

DataBaseSelect.java:

import java.sql.*;
import java.util.Vector;

public class DataBaseSelect {

private Vector result;

public DataBaseSelect() {
result = new Vector();
} // constructor DataBaseSelect

public String connect() {
try {
Class.forName("socketFactory=com.mysql.jdbc.NamedPipeSocketFactory").newInstance();
return "Driver Loaded!";
} catch (Exception E) {
return "Unable to load driver.";
}
}

public String select() {
try {
Connection C = DriverManager.getConnection("jdbc:mysql://localhost/test?user=xxxx&password=123");

Statement Stmt = C.createStatement();

ResultSet myResult = Stmt.executeQuery("SELECT * from users");

while (myResult.next()) {
result.addElement(myResult.getString(1));
}

// Clean up
myResult.close();
Stmt.close();
C.close();
return "Connection Success!";
} catch (SQLException E) {
return "SQLException: " + E.getMessage();
}
}

/**
* Accessor for result
**/
public Vector getResult() {
return result;
}

/**
* Mutator for result
**/
public void setResult(Vector avector) {
result = avector;
}

} // class DataBaseSelect

Select.jsp:

<html>
<head>
<title>Select everything from a database</title>
</head>
<body>

<jsp:useBean id="select" class="DataBaseSelect" scope="request">
</jsp:useBean>

<% out.print(select.connect()); %>
<br>
<% out.print(select.select()); %>

<p>Format results

<br>
<%@ page import="java.util.Vector" %>
<% Vector aResult = select.getResult(); %>

<table>
<% for (int i=0; i < aResult.size(); i++) { %>
<tr>
<td>
<% out.print(aResult.elementAt(i)); %>
</td>
</tr>
<% } %>
</table>

</body>
</html>

Thanks for the help!

**Nemi**

The DataBaseSelect class needs to be in the WEB-INF/classes directory

**bd30**

Hey,

The DataBaseSelect class is in the WEB-INF/classes directory, which is why this makes no sense to me. Anyone have an idea what could be causing this problem?

Thanks again for the help.

**Nemi**

FOr some reason putting class files in the root classes directory throws the app server for a loop (it is technically not good form to not use a package anyway). To get yours working you can import the class at the top of the jsp:

Code:

<%@ page import="DataBaseSelect" %>

Alternatively, if you put the DataBaseSelect in a package and qualify your useBean with the package name you can avoid this problem.

For instance, if you put the DataBaseSelect in a package called "db", you could use this in your jsp without any changes

Code:

<jsp:useBean id="select" class="db.DataBaseSelect" scope="request">

Hope that helps.

**bd30**

Hey,

I tried both of those suggestions but Tomcat is still generating an error message - either the same one if I do the page import line or an error indicating that the package db does not exist if I do the second suggestion.

Thanks for your help.

Dev Shed Forums

Thread: Problem with JSP/Beans/mySQL

Problem with JSP/Beans/mySQL