FULL PRODUCT VERSION :
Java(TM) SE Runtime Environment (build 1.7.0_25-b15)
Java HotSpot(TM) 64-Bit Server VM (build 23.25-b01, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Mac OS where Java 7 is available

A DESCRIPTION OF THE PROBLEM :

Exception in thread " AWT-EventQueue-3 " java.lang.ClassCastException: sun.lwawt.macosx.CPlatformEmbeddedFrame cannot be cast to sun.lwawt.macosx.CPlatformWindow
at sun.lwawt.macosx.CMouseInfoPeer.isWindowUnderMouse(CMouseInfoPeer.java:45)
at java.awt.Component.findUnderMouseInWindow(Component.java:1325)
at java.awt.Component.getMousePosition(Component.java:1377)
at javax.swing.plaf.synth.SynthSliderUI.calculateThumbLocation(SynthSliderUI.java:547)
at javax.swing.plaf.basic.BasicSliderUI$Handler.stateChanged(BasicSliderUI.java:1486)
at javax.swing.DefaultBoundedRangeModel.fireStateChanged(DefaultBoundedRangeModel.java:364)
at javax.swing.DefaultBoundedRangeModel.setRangeProperties(DefaultBoundedRangeModel.java:302)
at javax.swing.DefaultBoundedRangeModel.setValue(DefaultBoundedRangeModel.java:168)
at javax.swing.JSlider.setValue(JSlider.java:531)
at accordionsoft.AccordionSoft.jMenuItem4ActionPerformed(AccordionSoft.java:905)
at accordionsoft.AccordionSoft.access$4600(AccordionSoft.java:23)
at accordionsoft.AccordionSoft$20.actionPerformed(AccordionSoft.java:712)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.AbstractButton.doClick(AbstractButton.java:376)
at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:833)
at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:877)
at java.awt.Component.processMouseEvent(Component.java:6505)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6270)
at java.awt.Container.processEvent(Container.java:2229)
at java.awt.Component.dispatchEventImpl(Component.java:4861)
at java.awt.Container.dispatchEventImpl(Container.java:2287)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
at java.awt.Container.dispatchEventImpl(Container.java:2273)
at java.awt.Window.dispatchEventImpl(Window.java:2719)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:735)
at java.awt.EventQueue.access$200(EventQueue.java:103)
at java.awt.EventQueue$3.run(EventQueue.java:694)
at java.awt.EventQueue$3.run(EventQueue.java:692)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.awt.EventQueue$4.run(EventQueue.java:708)
at java.awt.EventQueue$4.run(EventQueue.java:706)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:705)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)


REGRESSION. Last worked in version 6u45

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Create an applet and add a JSlider

javax.swing.JSlider jslider = new javax.swing.JSlider;
jslider.setValue(50);

Run the applet


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
the jslider displays the value provided.
ACTUAL -
An Exception in java console.

ERROR MESSAGES/STACK TRACES THAT OCCUR :

Exception in thread " AWT-EventQueue-3 " java.lang.ClassCastException: sun.lwawt.macosx.CPlatformEmbeddedFrame cannot be cast to sun.lwawt.macosx.CPlatformWindow
at sun.lwawt.macosx.CMouseInfoPeer.isWindowUnderMouse(CMouseInfoPeer.java:45)
at java.awt.Component.findUnderMouseInWindow(Component.java:1325)
at java.awt.Component.getMousePosition(Component.java:1377)
at javax.swing.plaf.synth.SynthSliderUI.calculateThumbLocation(SynthSliderUI.java:547)
at javax.swing.plaf.basic.BasicSliderUI$Handler.stateChanged(BasicSliderUI.java:1486)
at javax.swing.DefaultBoundedRangeModel.fireStateChanged(DefaultBoundedRangeModel.java:364)
at javax.swing.DefaultBoundedRangeModel.setRangeProperties(DefaultBoundedRangeModel.java:302)
at javax.swing.DefaultBoundedRangeModel.setValue(DefaultBoundedRangeModel.java:168)
at javax.swing.JSlider.setValue(JSlider.java:531)
at accordionsoft.AccordionSoft.jMenuItem4ActionPerformed(AccordionSoft.java:905)
at accordionsoft.AccordionSoft.access$4600(AccordionSoft.java:23)
at accordionsoft.AccordionSoft$20.actionPerformed(AccordionSoft.java:712)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.AbstractButton.doClick(AbstractButton.java:376)
at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:833)
at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:877)
at java.awt.Component.processMouseEvent(Component.java:6505)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6270)
at java.awt.Container.processEvent(Container.java:2229)
at java.awt.Component.dispatchEventImpl(Component.java:4861)
at java.awt.Container.dispatchEventImpl(Container.java:2287)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
at java.awt.Container.dispatchEventImpl(Container.java:2273)
at java.awt.Window.dispatchEventImpl(Window.java:2719)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:735)
at java.awt.EventQueue.access$200(EventQueue.java:103)
at java.awt.EventQueue$3.run(EventQueue.java:694)
at java.awt.EventQueue$3.run(EventQueue.java:692)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.awt.EventQueue$4.run(EventQueue.java:708)
at java.awt.EventQueue$4.run(EventQueue.java:706)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:705)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
Create an applet and add a JSlider

javax.swing.JSlider jslider = new javax.swing.JSlider;
jslider.setValue(50);

Run the applet
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Don't use JSliders