While investigating this issue http://community.jboss.org/message/555195#555195, I have stumbled upon a MC deployer bug. Here's an simplified version of what's happening:
public class MyDeployer extends AbstractRealDeployerWithInput<JBossEnterpriseBeanMetaData>
implements
DeploymentVisitor<JBossEnterpriseBeanMetaData>
{
...
@Override
public void deploy(DeploymentUnit unit, JBossEnterpriseBeanMetaData beanMetaData) throws DeploymentException
{
doStepOne(); // like register component to some service name
doStepTwo(); // can be any operation which ends up throwing an runtime exception
}
@Override
public void undeploy(DeploymentUnit unit, JBossEnterpriseBeanMetaData enterpriseBean)
{
undoStepOne(); // i.e. unregister the service
}
}
As can be seen, the deploy() involves more than one step. The first step does registering of services (or some functionality internal to my deployer). The second step of deploy() does some other thing but ends up throwing an exception. I would expect that the undeploy() method
would be called on MyDeployer for this (failed) deployment unit, so that I can undo/cleanup whatever was done in doStepOne() of deploy() operation.
However, the undeploy() never gets called. Looking at MC's AbstractRealDeployerWithInput.deploy() method:
protected <U> void deploy(DeploymentUnit unit, DeploymentVisitor<U> visitor) throws DeploymentException
{
if (visitor == null)
throw new IllegalArgumentException("Null visitor.");
List<U> visited = new ArrayList<U>();
try
{
Set<? extends U> deployments = unit.getAllMetaData(visitor.getVisitorType());
for (U deployment : deployments)
{
visitor.deploy(unit, deployment);
visited.add(deployment);
}
}
catch (Throwable t)
{
for (int i = visited.size()-1; i >= 0; --i)
{
try
{
visitor.undeploy(unit, visited.get(i));
}
catch (Throwable ignored)
{
log.warn("Error during undeploy: " + unit.getName(), ignored);
}
}
throw DeploymentException.rethrowAsDeploymentException("Error deploying: " + unit.getName(), t);
}
}
More specifically:
visitor.deploy(unit, deployment);
visited.add(deployment);
visitor.deploy(...) throws the exception and hence the deployment is never added to "visited" which effectively means that in the catch block:
for (int i = visited.size()-1; i >= 0; --i)
{
try
{
visitor.undeploy(unit, visited.get(i));
}
catch (Throwable ignored)
{
log.warn("Error during undeploy: " + unit.getName(), ignored);
}
}
The "visited" will never contain this failed deployment. Ultimately, the undeploy() will never get called for that failed deployment unit.