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
/**
	 * return the query text. If the query text is empty then return the
	 * pre-defined pattern
	 * 
	 * @return
	 */
	private String getQueryText( )
	{
		String queryText = this.getDataSetDesign( ).getQueryText( );
		if ( queryText != null && queryText.trim( ).length( ) > 0 )
			return queryText;
		return SQLUtility.getQueryPresetTextString( this.getDataSetDesign( )
				.getOdaExtensionDataSetId( ) );
	}
	/*
	 * (non-Javadoc)
	 * @see org.eclipse.datatools.connectivity.oda.design.ui.wizards.DataSetWizardPage#cleanup()
	 */
	protected void cleanup( )
	{
		if ( metaDataProvider != null )
		{
			metaDataProvider.closeConnection( );
		}
	}
	/**
	 * Whether should the DatabaseObjectTree should be expanded.
	 * 
	 * @param expand True if the expanding is expected. Otherwise false.
	 */