Equinox Weaving QuickStart
Enabling Weaving for Plug-Ins with AspectJ
As of Eclipse Juno, these are the steps required to enable Equinox Weaving with AspectJ. Note that the aop.xml file is no longer necessary.
- Install the AspectJ Development Tooling (AJDT) and Equinox Weaving from the AJDT Downloads.
- Define your aspect(s) in a bundle.
- Configure your bundle's MANIFEST.MF to (i) export its aspects, and (ii) specify the bundles that its aspects advise. The former is done by adding a parameter on the Export-Package header. The latter is done through the Eclipse-SupplementBundle header. For example, a bundle with an aspect swing.edt.EdtRuleChecker, advising bundles com.example.core and com.example.ui would specify:
Export-Package: swing.edt;aspects="EdtRuleChecker" Eclipse-SupplementBundle: com.example.core, com.example.ui
- Add the following bundles to your launch configuration
- Ensure org.eclipse.equinox.weaving.aspectj is auto-started at, say, level 2
- Add the following VM argument (or to your config.ini) to instruct OSGi to load the weaving hooks:
Control How Aspects are Applied with 'aspect-policy'
Aspects can be defined as opt-in (bundles have to explicitly ask for the aspects to be installed) or opt-out (bundles must explicitly opt-out from weaving). Opt-out is the default policy. For example, to change the policy to opt-in:
Export-Package: swing.debug; aspects="EdtRuleChecker"; aspect-policy:=opt-in
Control How Aspects are Received with 'apply-aspects'
A bundle can explicitly request or forbid aspects being applied to it through the apply-aspects parameter on Import-Package:
Import-Package: swing.debug; apply-aspects:=false
apply-aspects defaults to true, indicating that aspects should be woven into the bundle, whereas false indicates that aspects should not be applied. These parameters override the supplying bundle's aspect-policy.
The Eclipse-BundleSupplement in effect causes the specified bundles to include Import-Package: ...; apply-aspects:=true for the packages that are exported by the aspects bundle.
For debugging output, add the following VM arguments:
-Daj.weaving.verbose=true -Dorg.aspectj.weaver.showWeaveInfo=true -Dorg.aspectj.osgi.verbose=true
- Martin Lippert (2009). What's New in Equinox Aspects. JAX 2009
- James Sugrue (2010). Aspect Oriented Programming for Eclipse Plug-ins. dZone.
- JDT Weaving Features