properties.clear(); properties.putAll(tableModel.getProperties());
    private void buildPropertiesAndApply() {        // Make sure there is no active cell editor anymore        TableCellEditor cellEditor = propertiesTable.getCellEditor();        if (cellEditor != null) {            cellEditor.stopCellEditing();        }        // Apply possibly changed properties.        properties.clear();        properties.putAll(tableModel.getProperties());        applyPropertiesToTiles();    }