A start level is defined to be a state of execution in which the Framework exists. StartLevel values are defined as unsigned integers with 0 (zero) being the state where the Framework is not launched. Progressively higher integral values represent progressively higher start levels. e.g. 2 is a higher start level than 1.
Access to the StartLevel service is protected by corresponding {@code ServicePermission}. In addition {@code AdminPermission}is required to actually modify start level information.
Start Level support in the Framework includes the ability to control the beginning start level of the Framework, to modify the active start level of the Framework and to assign a specific start level to a bundle. How the beginning start level of a Framework is specified is implementation dependent. It may be a command line argument when invoking the Framework implementation.
When the Framework is first started it must be at start level zero. In this state, no bundles are running. This is the initial state of the Framework before it is launched. When the Framework is launched, the Framework will enter start level one and all bundles which are assigned to start level one and whose autostart setting indicates the bundle should be started are started as described in the {@code Bundle.start} method. The Framework will continue to increasethe start level, starting bundles at each start level, until the Framework has reached a beginning start level. At this point the Framework has completed starting bundles and will then fire a Framework event of type {@code FrameworkEvent.STARTED} to announce it has completed itslaunch.
Within a start level, bundles may be started in an order defined by the Framework implementation. This may be something like ascending {@code Bundle.getBundleId} order or an order based upon dependenciesbetween bundles. A similar but reversed order may be used when stopping bundles within a start level.
The StartLevel service can be used by management bundles to alter the active start level of the framework.
@ThreadSafe
@noimplement
@author $Id: 42f3c6bbf682a69ea3914c737d5b0001694383db $
@deprecated This service has been replaced by theorg.osgi.framework.startlevel package.
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