Bug 209450 [regression]Duplicate values display in Cascading parameter list[0705]
Descripption: Duplicate values display in Cascading parameter list Build number:2.3.0.v20071112 Steps to reproduce: 1. New sample data source and dataset from CUSTOMERS. 2. New a cascading parameter from COUNTRY, STATE AND CITY fields. 3. Preview. Expected result: Values in three parameter list aren't duplicated. Actual result: Duplicate values show in parameter list. Error log:n/a
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/GetParameterDefinitionTask.java
ChoiceListCache cache = new ChoiceListCache( parameterHelpers );
			assert( parameterCount > 0 );
			return getSelectionTree( parameters, parameterHelpers, cache,
					new Object[0] );
		}
	}
	private Collection getSelectionTree( SlotHandle parameters,
			ParameterHelper[] parameterHelpers, ChoiceListCache cache,
			Object[] parameterValueAhead )
	{
		int parameterIndex = parameterValueAhead.length;
		int parameterCount = parameters.getCount( );
		ScalarParameterHandle parameter = (ScalarParameterHandle) parameters
				.get( parameterIndex );
		Collection choices = getChoicesFromParameterQuery( parameter );
		Iterator iterator = choices.iterator( );
		Collection result = null;
		while ( iterator.hasNext( ) )
		{
			Object[] values = new Object[parameterIndex + 1];
			for ( int i = 0; i < parameterValueAhead.length; i++ )
			{
				values[i] = parameterValueAhead[i];
			}
			IParameterSelectionChoice choice = (IParameterSelectionChoice) iterator
					.next( );
			Object value = choice.getValue( );
			values[parameterIndex] = value;
			Collection children = null;
			if ( parameterIndex == parameterCount - 1 )