Jerald,

If this is a similar ClassLoader issue, you can try explicitly sending a
(String)null to Cayenne for the driver name, forcing it to go through
the DriverManger, with which you will register your JDBC driver.

I have a similar situation in one of my applications, except that I am
forcing Cayenne to go through a different ClassLoader than the JVM's
default. You have the exact opposite case from mine, but my solution
should work for you as well, as long as you're able to instantiate the
JDBC driver.

http://bnubot.googlecode.com/svn/trunk/BNUBot/src/net/bnubot/db/conf/Cay
enneConfiguration.java


HTH,
Scott

-----Original Message-----
From: Jerald Dawson [mailto:[EMAIL PROTECTED] 
Sent: Tuesday, July 01, 2008 2:44 PM
To: [email protected]
Subject: Re: Exception in SAXParserFactory.newInstance with 3.0M4

Thanks Andrus

I got through that exception but now am getting another one where the  
org.apache.cayenne.conn.DriverDataSource is trying to load the jdbc  
driver class. I looked in the source and see that it is similar to the  
other code we were having issues with so I'm wondering if its the same  
thing. Here is the code in question where the exception is happening:

    private static Driver loadDriver(String driverClassName) throws  
SQLException {

         Class<?> driverClass;
         try {
             driverClass = Class.forName(driverClassName, true, Thread
                     .currentThread()
                     .getContextClassLoader());
         }
         catch (Exception ex) {
             throw new SQLException("Can not load JDBC driver named '"
                     + driverClassName
                     + "': "
                     + ex.getMessage());
         }
...

And here is the stack from the exception:
INFO: *** Connecting: FAILURE.
java.sql.SQLException: Can not load JDBC driver named  
'com.mysql.jdbc.Driver': com/mysql/jdbc/Driver
        at  
org 
.apache.cayenne.conn.DriverDataSource.loadDriver(DriverDataSource.java: 
62)
        at  
org 
.apache 
.cayenne 
.conn.DriverDataSource.setDriverClassName(DriverDataSource.java:256)

As you can see, driverClass is again using getContextClassLoad from  
Thread,currentThread(). Not 100% sure that its the issue but it seems  
reasonable. Also, I have verified that the mysql jars are in my  
classpath. Also, modeler seems to see it fine and is able to access my  
database.

jerald dawson

On Jul 1, 2008, at 1:18 PM, Andrus Adamchik wrote:

>> BTW, I'm using SWT if that is pertinent.
>
> It probably is. The ClassLoader settings are likely different.
>
> Anyways the code in question does look suspect. I implemented a bit  
> more paranoid version of this method (without actually knowing  
> whether null values are valid here or not). The code is checked in  
> to trunk, and you may try this cayenne-server.jar that contains the  
> fix:
>
>
http://people.apache.org/~aadamchik/patched/cayenne-server-3.0-07012008.
jar
>
> Andrus
>
>
>
>
> On Jul 1, 2008, at 9:02 PM, Jerald Dawson wrote:
>
>> Ok, more info. I have been stepping through the code to see what is  
>> actually throwing the NPE and I've come to this code in  
>> DataSourceInfo class:
>>
>>  public PasswordEncoding getPasswordEncoder() {
>>      PasswordEncoding encoder = null;
>>
>>      try {
>>          encoder = (PasswordEncoding) Thread
>>                  .currentThread()
>>                  .getContextClassLoader()
>>                  .loadClass(getPasswordEncoderClass())
>>                  .newInstance();
>>          // encoder = (PasswordEncoding)
>>          // Class.forName(getPasswordEncoderClass()).newInstance();
>>      }
>> ...
>>
>> Now following the code, I notice that the getContextClassLoader  
>> call returns null which seems to be the source of the NPE. Is there  
>> a reason getContextClassLoader would be returning null?
>>
>> BTW, I'm using SWT if that is pertinent.
>
>

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