We have a very strange error occurring at a developer site which we are unable to replicate ourselves.
A developer in Poland has recently upgraded his Windows XP Service Pack 3 machine to 4Gb of Ram When he did so he started experiencing graphical errors in java programs using IBM JDK 1.5 This errors only occur in IBM JDK 1.5 and not in any other version.
The problem manifests itself when you create a button or control on a form and move the mouse over it.
We have a test program
import java.awt.FlowLayout; import javax.swing.JButton; import javax.swing.JFrame; public class GraphicTest { public static void main(String args[]) { JFrame frame = new JFrame('GraphicTest'); frame.getContentPane().setLayout(new FlowLayout()); frame.setSize(200, 200); JButton button = new JButton('Test button'); button.setVisible(true); frame.getContentPane().add(button); frame.setVisible(true); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } } which shows the problem straight away.
However the problem doesn’t arise on my own machine when I upgrade the same windows version to 4Gb of Ram.
Has anyone else ever seen an issue like this?
Just to clarify this a bit, this issue only happens with IBM JDK 1.5 and only happens when we have 4Gb of Ram. It doesn’t happen on any other version of the JDKs and if we reduce the amount of memory to 3 Gb the problem disappears.
Try reducing the hardware optimization in Windows’ graphics drivers (accessible through the extended display control panel). If the machine in question has an onboard graphics adapter that uses a part of the main memory, then upgrading RAM might expose problems in the driver (or the RAM may even be faulty).