/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.aries.subsystem.core.internal;
import java.security.PrivilegedAction;
import org.osgi.service.subsystem.Subsystem.State;
import org.osgi.service.subsystem.SubsystemException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public abstract class AbstractAction implements PrivilegedAction<Object> {
private static final Logger logger = LoggerFactory.getLogger(AbstractAction.class);
protected final boolean disableRootCheck;
protected final BasicSubsystem requestor;
protected final BasicSubsystem target;
public AbstractAction(BasicSubsystem requestor, BasicSubsystem target, boolean disableRootCheck) {
this.requestor = requestor;
this.target = target;
this.disableRootCheck = disableRootCheck;
}
protected void checkRoot() {
if (!disableRootCheck && target.isRoot())
throw new SubsystemException("This operation may not be performed on the root subsystem");
}
protected void checkValid() {
BasicSubsystem s = (BasicSubsystem)Activator.getInstance().getSubsystemServiceRegistrar().getSubsystemService(target);
if (s != target)
throw new IllegalStateException("Detected stale subsystem instance: " + s);
}
protected void waitForStateChange(State fromState) {
long then = System.currentTimeMillis() + 60000;
synchronized (target) {
if (logger.isDebugEnabled())
logger.debug("Request to wait for state change of subsystem {} from state {}", target.getSymbolicName(), target.getState());
while (target.getState().equals(fromState)) {
if (logger.isDebugEnabled())
logger.debug("{} equals {}", target.getState(), fromState);
// State change has not occurred.
long now = System.currentTimeMillis();
if (then <= now)
// Wait time has expired.
throw new SubsystemException("Operation timed out while waiting for the subsystem to change state from " + fromState);
try {
if (logger.isDebugEnabled())
logger.debug("Waiting for {} ms", then - now);
// Wait will never be called with zero or a negative
// argument due to previous check.
target.wait(then - now);
}
catch (InterruptedException e) {
// Reset the interrupted flag.
Thread.currentThread().interrupt();
throw new SubsystemException(e);
}
}
if (logger.isDebugEnabled())
logger.debug("Done waiting for subsystem {} in state {} to change from state {}", new Object[]{target.getSymbolicName(), target.getState(), fromState});
}
}
}