Functional Item Type Factory for Units

How to Use FI Type Factory for Units

Functional Item type factory for Units corresponds with the FIM Factories feature. It provides meanings for defining new type factories for Units.

Functional Item (FI) TypeFactory is described in Type Factory section of the Developer Guide of the FIM module.

The main interfaces related to the units of measurement are available in com.prosyst.mbs.services.units package. The units are combined in a system, which can be used as an OSGi service with a unique name like "SI" for The International System of Units. The value can be expressed as a number and measured with a given unit. Such measured value is called quantity.

The FI TypeFactory for Units has:

• Supported Class – com.prosyst.mbs.services.units.Unit<Q> – represents a measurement unit supported by a system of units;
• UID – units:unit:factory;
• Creation Metadata requires the parameters:
  • symbol (String) – the unit symbol (mandatory);
  • systemName (String) – the unit belongs to the system with this name (optional).

  For more information refer to Supported Types for factories.

The FI TypeFactory for Units does not create a unit instance. It finds already created ones using the provided property values. This means that only units already available in the framework could be returned. They are discovered with com.prosyst.mbs.services.units.UnitUtil.getUnit(String, String). This method returns the unit recognized with the given symbol and in the given system. The system name is optional. If the system name is missing, the method will check all the available systems of units (refer to Java API for the complete list).

If the unit is not provided by a system of units, it cannot be discovered by the getUnit method and can not be used.