Browsing a PKCS#11 module will not work when path field is empty on first use

[ben221199]

Describe the bug
When installing and using KSE for the first time, browsing a PKCS#11 module will throw an error and not open the browse popup.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'File'
2. Go to 'Open Special'
3. Go to 'Open PKCS#11'
4. Make sure the path field is empty. If not, remove the app data files on your OS.
5. Click on the map icon
6. See the logs.

Screenshots

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException: Cannot invoke "String.trim()" because the return value of "javax.swing.JComboBox.getSelectedItem()" is null
        at org.kse.gui.dialogs.DOpenPkcs11KeyStore.browsePressed(DOpenPkcs11KeyStore.java:240)
        at org.kse.gui.dialogs.DOpenPkcs11KeyStore.lambda$initComponents$0(DOpenPkcs11KeyStore.java:182)
        at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1972)
        at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2314)
        at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:407)
        at java.desktop/javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:262)
        at java.desktop/javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:279)
        at java.desktop/java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:299)
        at java.desktop/java.awt.Component.processMouseEvent(Component.java:6621)
        at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3398)
        at java.desktop/java.awt.Component.processEvent(Component.java:6386)
        at java.desktop/java.awt.Container.processEvent(Container.java:2266)
        at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:4996)
        at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2324)
        at java.desktop/java.awt.Component.dispatchEvent(Component.java:4828)
        at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4948)
        at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4575)
        at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4516)
        at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2310)
        at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2780)
        at java.desktop/java.awt.Component.dispatchEvent(Component.java:4828)
        at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:775)
        at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:720)
        at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:714)
        at java.base/java.security.AccessController.doPrivileged(AccessController.java:400)
        at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)
        at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:98)
        at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:747)
        at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
        at java.base/java.security.AccessController.doPrivileged(AccessController.java:400)
        at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)
        at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:744)
        at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
        at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
        at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:117)
        at java.desktop/java.awt.WaitDispatchSupport$2.run(WaitDispatchSupport.java:191)
        at java.desktop/java.awt.WaitDispatchSupport$4.run(WaitDispatchSupport.java:236)
        at java.desktop/java.awt.WaitDispatchSupport$4.run(WaitDispatchSupport.java:234)
        at java.base/java.security.AccessController.doPrivileged(AccessController.java:319)
        at java.desktop/java.awt.WaitDispatchSupport.enter(WaitDispatchSupport.java:234)
        at java.desktop/java.awt.Dialog.show(Dialog.java:1079)
        at java.desktop/java.awt.Component.show(Component.java:1728)
        at java.desktop/java.awt.Component.setVisible(Component.java:1675)
        at java.desktop/java.awt.Window.setVisible(Window.java:1036)
        at java.desktop/java.awt.Dialog.setVisible(Dialog.java:1015)
        at org.kse.gui.actions.OpenPkcs11Action.doAction(OpenPkcs11Action.java:73)
        at org.kse.gui.actions.KeyStoreExplorerAction.actionPerformed(KeyStoreExplorerAction.java:108)
        at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1972)
        at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2314)
        at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:407)
        at java.desktop/javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:262)
        at java.desktop/javax.swing.AbstractButton.doClick(AbstractButton.java:374)
        at java.desktop/javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:986)
        at java.desktop/javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:1030)
        at java.desktop/java.awt.Component.processMouseEvent(Component.java:6621)
        at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3398)
        at java.desktop/java.awt.Component.processEvent(Component.java:6386)
        at java.desktop/java.awt.Container.processEvent(Container.java:2266)
        at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:4996)
        at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2324)
        at java.desktop/java.awt.Component.dispatchEvent(Component.java:4828)
        at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4948)
        at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4575)
        at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4516)
        at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2310)
        at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2780)
        at java.desktop/java.awt.Component.dispatchEvent(Component.java:4828)
        at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:775)
        at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:720)
        at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:714)
        at java.base/java.security.AccessController.doPrivileged(AccessController.java:400)
        at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)
        at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:98)
        at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:747)
        at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
        at java.base/java.security.AccessController.doPrivileged(AccessController.java:400)
        at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)
        at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:744)
        at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
        at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
        at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
        at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
        at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
        at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

Environment

• Version of KSE: 5.6.1
• Version of Java: 21
• Platform (OS): Debian on WSL (Windows 11)

[kaikramer]

Thank you very much for the bug report!

[ben221199]

No problem. It may or may not occur also on other dialogs too, but I haven't experienced it yet, because I only use the PKCS#11 part at this moment.