FULL PRODUCT VERSION :
java version "1.6.0-rc"

A DESCRIPTION OF THE PROBLEM :
Stack should be replaced with ArrayDeque where it appropiate.  It offers more flexibility in the interface and its methods are unsynchronized which should provied improved performance.  Ive identified these classes as potential users of Stack:
/javax/swing/ActionMap.java
/javax/swing/InputMap.java
/javax/swing/JComponent.java
/javax/swing/JEditorPane.java
/javax/swing/JMenu.java
/javax/swing/JRootPane.java
/javax/swing/JTree.java
/javax/swing/KeyboardManager.java
/javax/swing/MenuSelectionManager.java
/javax/swing/SwingUtilities.java
/javax/swing/SystemEventQueueUtilities.java
/javax/swing/UIDefaults.java
/javax/swing/filechooser/FileSystemView.java
/javax/swing/plaf/basic/BasicLookAndFeel.java
/javax/swing/plaf/basic/BasicMenuItemUI.java
/javax/swing/text/DefaultCaret.java
/javax/swing/text/DefaultStyledDocument.java
/javax/swing/text/ElementIterator.java
/javax/swing/text/StyleContext.java
/javax/swing/text/html/CSS.java
/javax/swing/text/html/CSSParser.java
/javax/swing/text/html/FrameView.java
/javax/swing/text/html/HTMLDocument.java
/javax/swing/text/html/HTMLWriter.java
/javax/swing/text/html/StyleSheet.java
/javax/swing/text/html/parser/Parser.java
/javax/swing/text/html/parser/TagStack.java
/javax/swing/text/rtf/RTFGenerator.java
/javax/swing/tree/DefaultMutableTreeNode.java
/javax/swing/tree/FixedHeightLayoutCache.java
/javax/swing/tree/VariableHeightLayoutCache.java

they should be audited and have their Stacks replaced with ArrayDeques.

REGRESSION.  Last worked in version mustang

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
read the source, their using the Stack

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
ArrayDeques being used.
ACTUAL -
Stacks everywhere!

REPRODUCIBILITY :
This bug can be reproduced always.

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read the source, their there.
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