Fix #1342: Show description of case converters as tooltip

CHANGELOG.md

@@ -27,6 +27,7 @@ We refer to [GitHub issues](https://github.com/JabRef/jabref/issues) by using `#
 - Integrity check table can be sorted by clicking on column headings
 - Added \SOFTWARE\Jabref 'Path' registry entry for installation path inside the installer
 - Added an additional icon to distinguish DOI and URL links ([feature request #696](https://github.com/JabRef/jabref/issues/696))
+- Implemented [#1342](https://github.com/JabRef/jabref/issues/1342): show description of case converters as tooltip 
 
 ### Fixed
 - Fixed [#473](https://github.com/JabRef/jabref/issues/473): Values in an entry containing symbols like ' are now properly escaped for exporting to the database

src/main/java/net/sf/jabref/gui/fieldeditors/contextmenu/CaseChangeMenu.java

@@ -34,6 +34,7 @@ public CaseChangeMenu(final JTextComponent parent) {
         // create menu items, one for each case changer
         for (final Formatter caseChanger : Formatters.CASE_CHANGERS) {
             JMenuItem menuItem = new JMenuItem(caseChanger.getName());
+            menuItem.setToolTipText(caseChanger.getDescription());
             menuItem.addActionListener(e -> parent.setText(caseChanger.format(parent.getText())));
             this.add(menuItem);
         }

src/main/java/net/sf/jabref/gui/fieldeditors/contextmenu/ConversionMenu.java

@@ -37,6 +37,7 @@ public ConversionMenu(JTextComponent opener) {
         // create menu items, one for each case changer
         for (Formatter converter : Formatters.CONVERTERS) {
             JMenuItem menuItem = new JMenuItem(converter.getName());
+            menuItem.setToolTipText(converter.getDescription());
             menuItem.addActionListener(e -> opener.setText(converter.format(opener.getText())));
             this.add(menuItem);
         }