Below are some screen shots of the screen refresh problems seen in a large medical diagnosis Java applet.  The refresh problems occur intermittently.  Typically they can be fixed by actions that trigger a screen refresh, such as hovering over a button to get a ToolTip to pop up or widening the Frame in which the applet runs. 

These problems are shown using Java 8 build 88 for Macintosh.  They occur in both Safari and Firefox, and also in 7.0_21.  The The problems never occur on Windows.

A typical example of a screen only partially drawn is below:

Here is the proper version, which appeared after eliciting a ToolTip from one of the properly displayed buttons:

It seems that screen refreshing was terminated before it finished, but triggering a screen refresh fixed the problem. 

Another example, first with the bad version in which part of the "Overwrite database" button from a different screen and part of a line (seen faintly under the "f" in "define") remain after switching to the current screen:

In the good version, obtained after triggering a ToolTip, the component "in MPS1,severe: Hurler syndrome" is drawn correctly and covers the material from the previous screen:

At other times, more from the previous screen remains to be drawn, but the only positions that have such residual display are positions in which components failed to draw:

Below is the good version.  This was one of the few examples in which triggering a ToolTip didn't fix the problem because the ToolTip failed to appear.  Often widening the Frame achieves the same as triggering a ToolTip in triggering a screen refresh, but in this case I returned to the previous screen and started this screen fresh to get the correct display:

If you have any comments please contact Mickey Segal.  A listing of  many Java resources is at this link.