How to add a facet to an existed project in my plug-in?

Question

In my plug-in on Workshop, I want to add a facet to a project dynamicly, and I try two ways, but it does't work:
1: use method "installProjectFacet"
facetedProject.installProjectFacet(fv,fv.createActionConfig(Action.Type.INSTALL,project.getName()), monitor);
The exception is :
org.eclipse.core.runtime.CoreException: Class com.bea.wlw.xmlbeans.feature.XMLBeansBuilderFeatureConfiguration$Factory is not an instance of org.eclipse.wst.common.project.facet.core.IActionConfigFactory.
at org.eclipse.wst.common.project.facet.core.internal.ProjectFacetVersion.createActionConfig(ProjectFacetVersion.java:141)
at ilog.integration.bea.workshop.AddXMLBeanFacet.execute(AddXMLBeanFacet.java:171)
2: use method setFixedProjectFacets
final Set <ProjectFacet> sourceFixed=facetedProject.getFixedProjectFacets();
                         Set <ProjectFacet> updatedFixed=new HashSet<ProjectFacet>();
                         Iterator it=sourceFixed.iterator();
                         while(it.hasNext()){
                              updatedFixed.add((ProjectFacet)it.next());
                         updatedFixed.add(f);
                         final Set <ProjectFacet> destFixed=updatedFixed;
                         facetedProject.setFixedProjectFacets(destFixed);
after executed, there is no changes.
Can you give me some advice?

Answer 1

After I add "org.eclipse.wst.common.project.facet.core" to my plug-in dependencies, the above exception does't appeared, the installProjectFacet can be executed without exception.
But when I release the plug-in and setup on workshop, there was a new exception when executed, I meets a new problem:
Root exception:
java.lang.NoClassDefFoundError: org/eclipse/wst/common/project/facet/core/IProjectFacet
at ilog.integration.bea.workshop.ui.shared.utils.AbstractArtifactsGenerator.importSchemas(AbstractArtifactsGenerator.java:138)
at ilog.integration.bea.workshop.ui.ws.WSArtifactsGenerator.createTypeMembers(WSArtifactsGenerator.java:93)
at ilog.integration.bea.workshop.ui.ws.pages.NewDecisionServiceWizardPage.createTypeMembers(NewDecisionServiceWizardPage.java:49)
at ilog.integration.bea.workshop.ui.shared.pages.NewTypeWizardPage.createType(NewTypeWizardPage.java:1844)
at ilog.integration.bea.workshop.ui.shared.wizards.DecisionServiceCreationWizard.finishPage(DecisionServiceCreationWizard.java:71)
at org.eclipse.jdt.internal.ui.wizards.NewElementWizard$2.run(NewElementWizard.java:117)
at org.eclipse.jdt.internal.core.BatchOperation.executeOperation(BatchOperation.java:39)
at org.eclipse.jdt.internal.core.JavaModelOperation.run(JavaModelOperation.java:718)
at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:1721)
at org.eclipse.jdt.core.JavaCore.run(JavaCore.java:3844)
at org.eclipse.jdt.internal.ui.actions.WorkbenchRunnableAdapter.run(WorkbenchRunnableAdapter.java:87)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:113)
Why can’t find the class IProjectFace? I haved added project facet plug-in into my plug-in dependencies, so I am confused. Does our plug-in needs other setting except eclipse plug-in's dependecies?
no pains, no gains