Bug 180608 [Regression]NPE throws out when preview the result in dataset[07]
Description: [Regression]NPE throws out when preview the result in dataset[07] Build number: 2.2.0.v20070403-0630 Steps to reproduce: 1, Use attached report 2, Edit Data Set 3, Preview the Data Set Expected result: The preview should be success Actual result: NPE throws out Error log:
data/org.eclipse.birt.data.tests/test/org/eclipse/birt/data/engine/binding/FeaturesTest.java
* 
	 * @throws Exception
	 */
	public void testBasicGetParameterMetaData1( ) throws Exception
	{
		String sql = "select COUNTRY, CITY from "
				+ getTestTableName( ) + " where city = ?";
		( (OdaDataSetDesign) this.dataSet ).setQueryText( sql );
		
		ParameterDefinition inputParamDefn = new ParameterDefinition( "param1",
				DataType.DECIMAL_TYPE,
				true,
				false );
		inputParamDefn.setPosition( 1 );
		inputParamDefn.setDefaultInputValue( "0" );
		( (OdaDataSetDesign) this.dataSet ).addParameter( inputParamDefn );
		QueryDefinition queryDefn = newReportQuery( );
		IPreparedQuery preparedQuery = dataEngine.prepare( queryDefn );
		Collection parameterMetaData = preparedQuery.getParameterMetaData( );
		assertTrue( parameterMetaData != null && parameterMetaData.size( ) == 1 );
		Iterator iter = parameterMetaData.iterator( );
		while ( iter.hasNext( ) )
		{
			IParameterMetaData paramMd = (IParameterMetaData) iter.next( );
			assertEquals( 1, paramMd.getPosition( ) );
			assertEquals( DataType.STRING_TYPE, paramMd.getDataType( ) );
			assertEquals( "param1", paramMd.getName( ) );
			assertEquals( "VARCHAR", paramMd.getNativeTypeName( ) );
			assertEquals( 0, paramMd.getScale( ) );
			assertEquals( 10, paramMd.getPrecision( ) );