Bug 202236 When select NULL value for multi-value parameter, cause NPE.
Description: When select NULL value for multi-value parameter, cause NPE. Build number: 2.2.1 Steps to reproduce: 1, New a list parameter, check Allow multi-value, uncheck isRequired 2, Select parameter data type as Date 3, Add some items into list 4, Preview 5, Select Null Value item in list Expected result: Can accept Null value for multi-value parameter Actual result: Cause NPE.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/EngineTask.java
Iterator iterator = inputValues.entrySet( ).iterator( );
		while ( iterator.hasNext( ) )
		{
			Map.Entry entry = (Map.Entry) iterator.next( );
			ParameterAttribute parameter = (ParameterAttribute) entry
					.getValue( );
			result.put( entry.getKey( ), parameter.getValue( ) );
		}
		return result;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.engine.api.IEngineTask#getParameterValue(java.lang.String)
	 */
	public Object getParameterValue( String name )
	{
		Object parameter = inputValues.get( name );
		if ( parameter == null )
		{
			return null;
		}
		assert parameter instanceof ParameterAttribute;
		return ( (ParameterAttribute) parameter ).getValue( );
	}
	public void setParameter( String name, Object value, String displayText )
	{
		parameterChanged = true;
		inputValues.put( name, new ParameterAttribute( value, displayText ) );
	}