Communication between Features

Features can communicate together through the use of Shared Interfaces. This mechanism is described in Shared Interfaces section.

For Applications to use the Shared Interface mechanism, a Kernel must provide:

  • an API for a first Application to register its Shared Interface, and for a second Application to get a proxy on it
  • a set of registered Kernel types converters

Kernel Service Registry

Although an Application can use another Application instance of a Shared Interface, it must, first, be provided a reference (a proxy of the other Application instance).

For that, a Kernel must provide an API for Applications to register and retrieve instances of shared interface: a KF service registry. Such registry can be implemented using the Kernel.bind() KF API to create a proxy for the requesting consumer Application.

Note that this can also be used for an Application instance of a Kernel type. In this case, a Converter must be defined and the converted instance is returned instead of creating a proxy.

An implementation of such KF service registry is provided by the Wadapps multisandbox implementation.

Kernel Types Converter

The Shared Interface mechanism allows to transfer an object instance of a Kernel type from one Feature to an other (see Transferable Types section).

To do that, the Kernel must register a new Kernel type converter. See the Converter class and Kernel.addConverter() method for more details.

The table below shows some converters defined in the com.microej.library.util#kf-util library.

Example of Available Kernel Types Converters
Type Converter Class Conversion Rule
java.lang.Boolean BooleanConverter Clone by copy
java.lang.Byte ByteConverter Clone by copy
java.lang.Character CharacterConverter Clone by copy
java.lang.Short ShortConverter Clone by copy
java.lang.Integer IntegerConverter Clone by copy
java.lang.Float FloatConverter Clone by copy
java.lang.Long LongConverter Clone by copy
java.lang.Double DoubleConverter Clone by copy
java.lang.String StringConverter Clone by copy InputStreamConverter Create a Proxy reference
java.util.Date DateConverter Clone by copy
java.util.List<T> ListConverter Clone by copy with recursive element conversion
java.util.Map<K,V> MapConverter Clone by copy with recursive keys and values conversion