The Device Access provides default implementation for device configurations.To use it, you should install and start com.prosyst.mbs.da.config.jar bundle. The default implementation allows you to create configurations in declarative form. That is the configurations are stored in XML files validated by the following XSD Schema. The XML configurations are provided by separated bundle. This bundle has specific manifest header which is described further bellow.

The configuration XML file semantically can be separated into three logical parts:

• information about the configuration and how the configuration is to be applied,
• filtering and configuring of the devices,
• filtering and configuring of the device items.

The main idea is to describe a restriction for which Devices to be applied the configuration using device filtering and device item filtering. The device filtering and item filtering together determine whether the device matches the configuration. After the device is matched to the configuration, it should be configured using the descriptions in the device configuring section. The device items configuration are going to be applied after the device and device item filtering have matched.

Detailed information for device configuring is organized in the following sections:

• Device Configuration Information – provides detailed information about the configuration and how the configuration is going to be applied.
• Device Configuration – provides detailed information about the device filtering and device configuring.
• Device Item Configuration – provides detailed information about the device item filtering and device item configuring.
• Device Configuration Example – provides a simple example of XML configuration file.

Manifest Header

The bundle that provides XML device configurations should have special manifest header - "DAConfig" that has two attributes:

• xml – this attribute declares the path to the XML device configuration file. This is a mandatory attribute.
• version – this attribute declares the version of the XML file. It is an optional attribute. If there is no specified version, the default 0.0.0 version is used. This attribute is transformed into correct OSGi version (org.osgi.framework.Version) format. The version attribute, except as a XML file version, is used for the configuration version. It is possible to have more than one configurations in one XML file. This means that these configurations will have the same versions – the version of the XML file.

The following examples show valid manifest headers:

DAConfig:

• xml=/resources/xml/configs.xml;version="1.0.0"
• xml=/resources/xml/configs1.xml;version=1.0.1
• xml=/resources/xml/configs2.xml

The next example shows the manifest header of the Device Access Configuration Demo bundle.

DAConfig:

xml=/xml/config/device-configuration.xml;version = "1.0.0",

xml=/xml/config/device-item-configuration.xml;version = "1.0.0",

xml=/xml/config/device-item-configuration-retry.xml;version = "1.0.0"