Public:BWmeta service/Java mapping

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Service details
Name	BWmeta
Code location (relative to SVN root)	projects/dir/bwmeta-core
Javadoc
Contact person	Jakub Jurkiewicz
edit BWmeta format Data Model BWMeta Model Design principles 1.0.5 example 1.2.0 example 2.0.0 example Feature requests Linked Open Data Hierarchys Book Journal BWmeta usage in YADDA Java mapping Rich text in Java mapping Transformers data sources Conventions and constants Contents and attachments Internationalization Tutorial How to convert to Dublic Core? Categorizations

Contents 1 History 2 General contracts 3 Nulls and empty texts 4 Rich text support

History

Three different mappings of BWmeta to Java have been written in the project's lifetime. The following table summarizes the mappings.

Model Name	Works with BWmeta versions	Usage areas	Comments
Repo model	1.0.0 ÷ 1.0.5	Processes, YaddaWeb	Hibernate-oriented
DeskLight model	1.0.0 ÷ 1.0.5	Processes, DeskLight
"Y" model	1.2.0 ÷ 2.0.0	Pack Management

Current efforts are focused on replacing the older models (Repo and DeskLight) with the latest one ("Y"). The remainder of this page and all the other pages on BWmeta usage in YADDA assume usage of the "Y" model.

General contracts

Unless explicitly stated in the documentation, every "Y" class has the following properties:

• has a public default constructor.
• every property is protected, but has a public getter and setter.
• getters of String, YLanguage and List properties can never return null. Instead, an empty String, YLanguage.Undetermined or an empty List is returned, respectively.
• for every List<T> property:
  • its getter returns a modifiable List<T>;
  • its getter returns the same reference all the time;
  • its setter accepts any Collection<T> (and copies the contents);
  • there's an adder (which returns this).
• every setter and every list adder returns this, which allows chained setting, e.g.:

new YElement()
    .setId("bwmeta1.element.foo")
    .addName(new YName().setText("Foo").setLanguage(YLanguage.English))
    .addDescription(new YDescription().setText("Lorem ipsum").setLanguage(YLanguage.Latin));

The folowing contracts are to be implemented/verified in the future:

• hashCode() and equals() methods are based on the values of all the properties, i.e., two "Y" objects are equal iff they are of the same type and all their properties are equal.

Nulls and empty texts

In general nulls are not acceptible in places where should be text(String, YRichtext). If such field is set to null value then empty string is set automatically. Nulls are not returned from this fileds. Only exceptions that exists in system when nulls value are accepted on string fields are:

• Identity w contributorze
• TODO: tu wpisujemy miejsca gdzie są nulle

Rich text support

See BWmeta service/Java mapping/Rich text.