Static Map type variable assignment initial value

private static Map<String,String> sysTypeList = new HashMap<String, String>();  
    static {
        sysTypeList.put( "1", "System Parameters" );
        sysTypeList.put( "2", "Interface Parameters" );
        sysTypeList.put( "3", "System function" );
        sysTypeList.put( "4", "Device Platform" );
    }