Bug 145478 Unable "Select Value" in the Join data set's filter
Step to reproduce: 1.new a join data set(please use the attached file) 2.right click the dataset and click the Edit 3.go to the Filter pane and set a filer 4.click the list of Value1 Actual result: A warning pop up and cant select Value.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/data/ui/util/DataSetProvider.java
{
		 
		 
		
		
		
		
		String classPath = System.getProperty( "workspace.projectclasspath" );
		if ( classPath == null || classPath.length( ) == 0  )
			return parent;
		
		String[] classPathArray = classPath.split( ";", -1 );
		int count = classPathArray.length; 
		URL[] urls = new URL[count];
		for ( int i = 0; i < count; i++ )
		{
			File file = new File( classPathArray[i] );
			try
			{
				urls[i] = file.toURL( );
			} catch ( MalformedURLException e )
			{
				urls[i] = null;
			}
		}
		return new URLClassLoader( urls, parent);
	}
	
}