Bug 187162 [Regression]NPE throws out when open a dataset which reference datasource has no driver[07]
Description: NPE throws out when open a dataset which reference datasource has no driver[07] Build number: 2.2.0.v20070516-0630 Steps to reproduce: 1, open a dataset makesure the datasource has no driver 2, Close all the warning dialog and the dataset dialog 3, Check the error log Expected result: No NPE throws out Actual result: NPE throws out Error log: java.lang.NullPointerException at org.eclipse.birt.report.data.oda.jdbc.ui.editors.SQLDataSetEditorPage.refreshPage(SQLDataSetEditorPage.java:1376) at org.eclipse.birt.report.data.oda.jdbc.ui.editors.SQLDataSetEditorPage.initializeControl(SQLDataSetEditorPage.java:272) at org.eclipse.birt.report.data.oda.jdbc.ui.editors.SQLDataSetEditorPage.createPageCustomControl(SQLDataSetEditorPage.java:191) at org.eclipse.datatools.connectivity.oda.design.ui.wizards.DataSetWizardPage.createControl(DataSetWizardPage.java:123) at org.eclipse.datatools.connectivity.oda.design.internal.ui.DataSetEditorPageCore.createContents(DataSetEditorPageCore.java:73) at org.eclipse.jface.preference.PreferencePage.createControl(PreferencePage.java:233) at org.eclipse.birt.report.designer.data.ui.dataset.PropertyPageWrapper.createPageControl(PropertyPageWrapper.java:45) at org.eclipse.birt.report.designer.data.ui.property.PropertyNode.createPageControl(PropertyNode.java:238) at org.eclipse.birt.report.designer.data.ui.property.AbstractPropertyDialog.showPage(AbstractPropertyDialog.java:442) at org.eclipse.birt.report.designer.data.ui.property.AbstractPropertyDialog.showSelectionPage(AbstractPropertyDialog.java:346) at org.eclipse.birt.report.designer.data.ui.dataset.DataSetEditor.showSelectionPage(DataSetEditor.java:720) at org.eclipse.birt.report.designer.data.ui.property.AbstractPropertyDialog$2.run(AbstractPropertyDialog.java:304)
data/org.eclipse.birt.report.data.oda.jdbc.ui/src/org/eclipse/birt/report/data/oda/jdbc/ui/editors/SQLDataSetEditorPage.java
GridLayout layout = new GridLayout( );
		layout.numColumns = 1;
		composite.setLayout( layout );
		CompositeRuler ruler = new CompositeRuler( );
		LineNumberRulerColumn lineNumbers = new LineNumberRulerColumn( );
		ruler.addDecorator( 0, lineNumbers );
		viewer = new SourceViewer( composite, ruler, SWT.H_SCROLL
				| SWT.V_SCROLL );
		sourceViewerConfiguration = new JdbcSQLSourceViewerConfiguration( );
		viewer.configure( sourceViewerConfiguration );
		doc = new Document( getQueryText( ) );
		FastPartitioner partitioner = new FastPartitioner( new SQLPartitionScanner( ),
				new String[]{
						SQLPartitionScanner.SINGLE_LINE_COMMENT1,
						SQLPartitionScanner.SINGLE_LINE_COMMENT2,
						SQLPartitionScanner.MULTI_LINE_COMMENT,
						IDocument.DEFAULT_CONTENT_TYPE
				} );
		partitioner.connect( doc );
		doc.setDocumentPartitioner( partitioner );
		viewer.setDocument( doc );
		viewer.getTextWidget( ).setFont( JFaceResources.getTextFont( ) );
		viewer.getTextWidget( )
				.addBidiSegmentListener( new BidiSegmentListener( ) {
					/*
					 * @see org.eclipse.swt.custom.BidiSegmentListener#lineGetSegments(org.eclipse.swt.custom.BidiSegmentEvent)
					 */
					public void lineGetSegments( BidiSegmentEvent event )
					{
						event.segments = SQLUtility.getBidiLineSegments( event.lineText );