It is seen that using VK_F4 in JButton's setMnemonic(int i), causes the letter 'S' in the JButton to be underlined if JButton's text has 'S' in its string. This is because [**VK_F4**](https://github.com/openjdk/jdk/blob/master/src/java.desktop/share/classes/java/awt/event/KeyEvent.java#L506) keycode is 0x73 (115 in decimal) which happens to be value of lowercase [**'s'** ](https://www.cs.cmu.edu/~pattis/15-1XX/common/handouts/ascii.html) so as per the logic implemented in SwingUtilities.findDisplayedMnemonicIndex(), the first index of the character (either lowecasr or uppercase) is returned as a mnemonic, which gets underlined.
Fix is made to ignore Action Keys from VK_F1->VK_F11 as displayed mnemonic which corresponds to lowercase p->z ------------- Commit messages: - Fix - Fix - 4850101: Setting mnemonic to VK_F4 underlines the letter S in a button. Changes: https://git.openjdk.org/jdk/pull/9712/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9712&range=00 Issue: https://bugs.openjdk.org/browse/JDK-4850101 Stats: 139 lines in 2 files changed: 139 ins; 0 del; 0 mod Patch: https://git.openjdk.org/jdk/pull/9712.diff Fetch: git fetch https://git.openjdk.org/jdk pull/9712/head:pull/9712 PR: https://git.openjdk.org/jdk/pull/9712
