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postgres jdbc class problem

From: Richard Morrell <richard(at)ednet(dot)co(dot)uk>
To: pgsql-interfaces(at)postgresql(dot)org
Subject: postgres jdbc class problem
Date: 1999-09-30 16:10:35
Message-ID: Pine.LNX.3.96.990930162012.19261B-100000@faure.ednet.co.uk (view raw or flat)
Thread:
Lists: pgsql-interfaces
Hi,

I'm writing a simple java applet that queries a postgres database using
JDBC.  The applet works fine in the appletviewer and in some copies of
Netscape and MSIE.  However, in most copies of Netscape and MSIE it
returns a NullPointerException.  The java console error messages aren't
that helpful, so I looked at my web server logs.  For the browsers which
are failing I noticed that they are requesting extra class files which
don't seem to be part of the postgres jdbc driver: 

[Thu Sep 30 15:28:05 1999] [error] [client 195.89.132.20] File does not
exist: /home/richard/public_html/postgresql/errors_en_US.class
[Thu Sep 30 15:28:05 1999] [error] [client 195.89.132.20] File does not
exist: /home/richard/public_html/postgresql/errors_en.class
[Thu Sep 30 15:28:05 1999] [error] [client 195.89.132.20] File does not
exist: /home/richard/public_html/postgresql/errors_en_US.class
[Thu Sep 30 15:28:05 1999] [error] [client 195.89.132.20] File does not
exist: /home/richard/public_html/postgresql/errors_en.class
[Thu Sep 30 15:28:05 1999] [error] [client 195.89.132.20] File does not
exist: /home/richard/public_html/postgresql/errors.class

Here is the java console message from netscape 4.6:

Netscape Communications Corporation -- Java 1.1.5
Type '?' for options.
Symantec Java! ByteCode Compiler Version 210.065
Copyright (C) 1996-97 Symantec Corporation
# Applet exception: java.lang.NullPointerException
java.lang.NullPointerException
  at postgresql.util.PSQLException.translate(Compiled Code)
  at postgresql.util.PSQLException.<init>(Compiled Code)
  at postgresql.Driver.connect(Compiled Code)
  at java.sql.DriverManager.getConnection(Compiled Code)
* at java.sql.DriverManager.getConnection(Compiled Code)
  at OutputApplet.run(Compiled Code)
  at java.lang.Thread.run(Compiled Code)
java.io.IOException: CreateProcess: vcafe -netscape error=0
  at java.lang.Win32Process.<init>(Compiled Code)
  at java.lang.Runtime.exec(Compiled Code)
* at java.lang.Runtime.exec(Compiled Code)
  at netscape.debug.Debugger.launchDebugger(Compiled Code)
  at netscape.debug.Debugger.uncaughtException(Compiled Code)
  at netscape.applet.AppletThreadGroup.uncaughtException(Compiled Code)

I'm using postgres 6.5.1 with the new 6.5.1-2 JDBC driver that I
downloaded from www.retep.org.uk.  My code is faily straightforward:

public void run() {
	String url = "jdbc:postgresql://faure.ednet.co.uk/software";
	String query = "select * from software";

	try {
	    // Class.forName("postgresql.Driver");
	DriverManager.registerDriver((Driver)Class.forName("postgresql.Driver").newInstance());
	} catch(Exception ex) {
	    setError("driver class: " + ex);
	    return;
	}

	try {
	    Vector results = new Vector();
	    Connection con = DriverManager.getConnection(url,
						"username", "password");
	    Statement stmt = con.createStatement();
	    ResultSet rs = stmt.executeQuery(query);
	    while (rs.next()) {
		String s = rs.getString("description");
		int level = rs.getInt("ladder_level");
		String text = level + "   " + s;
		results.addElement(text);
	    }

	    stmt.close();
	    con.close();

	    setResults(results);

	} catch(SQLException ex) {
	    setError("SQLException: " + ex);
	}


Does anyone have any ideas about what might be wrong here?

--
Richard Morrell                                           richard(at)ednet(dot)co(dot)uk
Operations Manager - edNET: InternetWorkingSolutions - http://www.ednet.co.uk







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Subject: Web Interfaces Information
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