Bug 73984 Editing user library jar path after path change does not work [build path]
1) Create a directory containing jar file 2) Add this jar file to a new user library 3) Rename directory from 1) 4) Update the path to jar file in user libraries (select old jar reference, select new location in browser, open -> path is not updated, but old path is still used
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/UserLibraryPreferencePage.java
}
		
		private IStatus validateSettings() {
			String name= fLocationField.getText();
			fLastFile= null;
			if (isSave()) {
				if (name.length() == 0) {
					return new StatusInfo(IStatus.ERROR, PreferencesMessages.getString("UserLibraryPreferencePage.LoadSaveDialog.location.error.save.enterlocation")); 
				}
				File file= new File(name);
				if (file.isDirectory()) {
					return new StatusInfo(IStatus.ERROR, PreferencesMessages.getString("UserLibraryPreferencePage.LoadSaveDialog.location.error.save.invalid")); 
				}
				if (fExportImportList.getCheckedSize() == 0) {
					return new StatusInfo(IStatus.ERROR, PreferencesMessages.getString("UserLibraryPreferencePage.LoadSaveDialog.list.error.save.nothingselected")); 
				}
				fLastFile= file;
			} else {
				if (name.length() == 0) {
					return new StatusInfo(IStatus.ERROR, PreferencesMessages.getString("UserLibraryPreferencePage.LoadSaveDialog.location.error.load.enterlocation")); 
				}
				if (!new File(name).isFile()) {
					return new StatusInfo(IStatus.ERROR, PreferencesMessages.getString("UserLibraryPreferencePage.LoadSaveDialog.location.error.load.invalid")); 
				}
				if (fExportImportList.getSize() > 0 && fExportImportList.getCheckedSize() == 0) {
					return new StatusInfo(IStatus.ERROR, PreferencesMessages.getString("UserLibraryPreferencePage.LoadSaveDialog.list.error.load.nothingselected")); 
				}
			}
			return new StatusInfo();
		}