The 'Properties' field 'java.awt.Cursor#systemCustomCursorProperties' contains only non-null values. It means we can use 'get'+null check instead of 'containsKey'+'get' calls in the method 'java.awt.Cursor#getSystemCustomCursor'.

            if (!systemCustomCursorProperties.containsKey(key)) {
                if (log.isLoggable(PlatformLogger.Level.FINER)) {
                    log.finer("Cursor.getSystemCustomCursor(" + name + ") returned null");
                }
                return null;
            }
            final String fileName =
                systemCustomCursorProperties.getProperty(key);

It's clearer and a bit faster.