Bean Tutorial - Using your own API !

Yes, it can be done! To access the contents of sections you can use any of your self-defined Java Beans compatible API. In order to do this you only have to create a Java Beans-style interface or class.

Source code for beans: Dwarf, DwarfBean

Code sniplets in this tutorial tested with the following .ini file: dwarfs.ini

Accessing sections as beans

While writing a program we usually know the type of the section's values, so we can define one or more java interfaces to access them. An advantage of this solution is that the programmer doesn't have to convert the values because they are converted automatically to the type defined in the interface.

Ofcourse you may use setters as well, not just getters. In this way you can change values type safe way.

    void sample01(Ini ini)
        Ini.Section sec = ini.get("happy");
        Dwarf happy =;
        int age = happy.getAge();
        URI homePage = happy.getHomePage();


The happy instanceof Dwarf relation is of course fulfilled in the example above.

Marshalling beans

Sometimes we want to store existing java beans in text file. This operation usually called marshalling.

With [ini4j] it is easy to store bean properties in a section. You simply create a section, and call the sections's from() method. Thats it.

    void sample02(Ini ini)
        DwarfBean sleepy = new DwarfBean();

        Ini.Section sec = ini.add("sleepy");


Unmarshalling beans

If you have a marshalled bean in text file then you may want to read it into bean. This operation usually called unmarshalling.

With [ini4j] it is easy to load bean properties from a section. You simply instantiate a bean, and call the sections's to() method. Thats it.

    void sample03(Ini ini)
        DwarfBean grumpy = new DwarfBean();


Indexed properties

For handling indexed properties, you should allow mulpti option value handling in configuration. After enabling this feature, option may contains multiply values (multi line in file). These values can mapped to indexed bean property.

    void sample04(URL location) throws IOException
        Config cfg = new Config();

        Ini ini = new Ini();

        Ini.Section sec = ini.get("sneezy");
        Dwarf sneezy =;
        int[] numbers = sneezy.getFortuneNumber();

        // same as above but with unmarshalling...
        DwarfBean sneezyBean = new DwarfBean();;
        numbers = sneezyBean.getFortuneNumber();


Not only Ini and Ini.Section has bean interface. There is a bean interface for OptionMap class and each derived class for example for Options. Options is an improved java.util.Properties replacement.

    void sample05(Options opts)
        Dwarf dwarf =;
        int age = dwarf.getAge();

        // same as above but with unmarshalling
        DwarfBean dwarfBean = new DwarfBean();;
        age = dwarfBean.getAge();

In sample above the top level properties (like "age") mapped to bean properties.

Prefixed mapping

Both Ini.Section and Options has possibility to add a prefix to property names while mapping from bean property name to Ini.Section or Options key.

    void sample06(URL optPath) throws IOException
        Options opt = new Options(optPath);
        Dwarf dwarf =, "happy.");
        DwarfBean bean = new DwarfBean();, "dopey.");

In the above example, dwarf bean will contain properties starts with happy. while bean will contain properties starts with dopey.