[FELIX-3306] Lazy activation of bundles is not always working as expected

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: framework-4.0.2
• Fix Version/s: framework-4.2.0
• Component/s: Framework
• Assignee: Richard S. Hall
• Reporter: Bogdan Stefanescu
• Created: 16/Jan/12 15:01
• Updated: 16/Jun/12 19:10
• Resolved: 16/Jun/12 19:10

Description

When loading a class from a "lazy" bundle (e.g. Bundle-ActivationPolicy: lazy) the bundle is not always activated.
More precisely, when a bundle is triggering the activation of a chain of more than one lazy bundle (due to a class loading) not all the bundles in the chain are activated.

Example:
Let say we have 3 bundles: bundle1, bundle2 and bundle3. All those bundles are defining a lazy activation via: 'Bundle-ActivationPolicy: lazy'.
In the activator of bundle1 we load a class from bundle2. In activator of bundle2 we load a class from bundle3.
By starting (from the felix command line) the bundle1 - only the bundle2 will be activated even if the class from bundle3 is successfully loaded by the activator of bundle2.

You can find attached 3 bundles you can use to reproduce the bug. (they also contains the source code)

To reproduce the bug:
Install a felix 4.0.2 (or 4.2.0-SNAPSHOT) and add the plugin "org.apache.felix.fileinstall"
Configure the fileinstall plugin to load the bundles located inside the directory ./plugins:

felix.fileinstall.dir=./plugins

and put there the 3 bundles attached to the issue.

After starting Felix by typing "lb -s" I have:

START LEVEL 1
   ID|State      |Level|Symbolic name
    0|Active     |    0|org.apache.felix.framework (4.0.2)
    1|Active     |    1|org.apache.felix.bundlerepository (1.6.6)
    2|Active     |    1|org.apache.felix.fileinstall (3.1.10)
    3|Active     |    1|org.apache.felix.gogo.command (0.12.0)
    4|Active     |    1|org.apache.felix.gogo.runtime (0.10.0)
    5|Active     |    1|org.apache.felix.gogo.shell (0.10.0)
    6|Starting   |    1|bundle3 (1.0.0.201201161439)
    7|Starting   |    1|bundle1 (1.0.0.201201161439)
    8|Starting   |    1|bundle2 (1.0.0.201201161439)

which is OK since the 3 bundles are declared as "lazy" so they will enter the STARTING state.
Now start the bundle1 by typing "start 7". I have the following output:

>>> Bundle3Object loaded
Sarted bundle: bundle2
>>> Bundle2Object loaded
Started Bundle: bundle1

and typing again "lb -s" I have:

START LEVEL 1
   ID|State      |Level|Symbolic name
    0|Active     |    0|org.apache.felix.framework (4.0.2)
    1|Active     |    1|org.apache.felix.bundlerepository (1.6.6)
    2|Active     |    1|org.apache.felix.fileinstall (3.1.10)
    3|Active     |    1|org.apache.felix.gogo.command (0.12.0)
    4|Active     |    1|org.apache.felix.gogo.runtime (0.10.0)
    5|Active     |    1|org.apache.felix.gogo.shell (0.10.0)
    6|Starting   |    1|bundle3 (1.0.0.201201161439)
    7|Active     |    1|bundle1 (1.0.0.201201161439)
    8|Active     |    1|bundle2 (1.0.0.201201161439)

Which is NOT OK, since the bundle2 is loading a class 'Bundle3Object' from bundle3 in the activator - the bundle3 must be activated too but it is not.
You can see in the log made by bundle2 that Bundle3Object is correctly loaded (but the bundle3 not activated).

(You can see the bundle2 was correctly activated by bundle1 by loading a class from bundle2 but the bundle3 is not activated when bundle2 is loading a class from bundle3)

The fileinstall plugin seems to work correctly. I think the problem is in BundleWiringImpl$BundleClassLoader.findClass()