Bug 194549 Memory leak in chart device renderers
After memory analysis for Chart code, it indicates java.awt.Font objects are not garbage collected. Investigating the renderer code, Graphics2D objects in IDisplayServer and IDeviceRenderer are not disposed after chart rendering finished. Need to invoke IDeviceRenderer.dispose() after ChartReportItemPresentationImpl being finished, and dispose all required resources in that method, including IDisplayServer and anything else.
chart/org.eclipse.birt.chart.device.swt/src/org/eclipse/birt/chart/device/swt/SwtTextRenderer.java
}
	/**
	 * @param ipr
	 * @param lo
	 * @param la
	 * @param b
	 */
	private void showBottomValue( IPrimitiveRenderer ipr, Location lo,
			Label la, boolean b )
	{
		
	}
	/**
	 * @param ipr
	 * @param lo
	 * @param la
	 * @param b
	 */
	private void showTopValue( IPrimitiveRenderer ipr, Location lo, Label la,
			boolean b )
	{
		GC gc = (GC) ( (IDeviceRenderer) ipr ).getGraphicsContext( );
		double dX = lo.getX( ), dY = lo.getY( );
		final FontDefinition fd = la.getCaption( ).getFont( );
		final double dAngleInDegrees = fd.getRotation( );
		final double dAngleInRadians = Math.toRadians( dAngleInDegrees );
		final Color clrBackground = (Color) _sxs.getColor( la.getShadowColor( ) );
		final ITextMetrics itm = new SwtTextMetrics( _sxs, la );
		final double dFW = itm.getFullWidth( );
		final double dFH = itm.getFullHeight( );