Bug 191644 Dataset don't be cached in Chart Builder.
Build ID: I20070517-1700 Birt Steps To Reproduce: 1. New a Chart. 2. Set dataset from remote db. 3. Switch tabs of Chart Builder, it is OK. 4. Shut off network. 5. Switch tabs of Chart Builder again. 6. Some exception will throw, it shows the db accessing is fail. Expected Result: The dataset should be cached. Actual Result: It looks like the dataset don't be cached. More information:
chart/org.eclipse.birt.chart.reportitem.ui/src/org/eclipse/birt/chart/reportitem/ui/ReportDataServiceProvider.java
page.setExpressionProvider( ep );
		return page.open( );
	}
	private StyleHandle[] getAllStyleHandles( )
	{
		List sLst = getReportDesignHandle( ).getAllStyles( );
		StyleHandle[] list = (StyleHandle[]) sLst.toArray( new StyleHandle[sLst.size( )] );
		Arrays.sort( list, new Comparator( ) {
			Collator collator = Collator.getInstance( ULocale.getDefault( ) );
			public int compare( Object o1, Object o2 )
			{
				StyleHandle s1 = (StyleHandle) o1;
				StyleHandle s2 = (StyleHandle) o2;
				return collator.compare( s1.getDisplayLabel( ),
						s2.getDisplayLabel( ) );
			}
		} );
		return list;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.chart.ui.interfaces.IDataServiceProvider#getAllStyles()
	 */
	public String[] getAllStyles( )
	{
		StyleHandle[] handles = getAllStyleHandles( );
		String[] names = new String[handles.length];
		for ( int i = 0; i < names.length; i++ )
		{