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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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package org.jgroups.stack;

import org.jgroups.logging.Log;
import org.jgroups.protocols.TP;
import org.jgroups.util.ShutdownRejectedExecutionHandler;

import java.util.concurrent.RejectedExecutionHandler;
import java.util.concurrent.ThreadPoolExecutor;

/**
 * If either {@link org.jgroups.protocols.UNICAST3} or {@link org.jgroups.protocols.pbcast.NAKACK2} are missing, then
 * this policy checks that the thread pool has a rejection policy of
 * {@link java.util.concurrent.ThreadPoolExecutor.CallerRunsPolicy}.

 * Issues a warning and changes the rejection policy to {@link java.util.concurrent.ThreadPoolExecutor.CallerRunsPolicy}
 * if not.
 * @author Bela Ban
 * @since  5.2.14
 */
public class CheckCallerRunsPolicy implements Policy {

    protected static final Class UNICAST3=org.jgroups.protocols.UNICAST3.class,
      NAKACK2=org.jgroups.protocols.pbcast.NAKACK2.class;

    @Override
    public void check(Protocol prot) throws Exception {
        if(!(prot instanceof TP))
            throw new IllegalStateException(String.format("%s needs to be run in the scope of a transport",
                                                          CheckCallerRunsPolicy.class.getSimpleName()));
        TP tp=(TP)prot;
        ProtocolStack stack=tp.getProtocolStack();
        Log log=tp.getLog();
        if(stack.findProtocol(UNICAST3) == null || stack.findProtocol(NAKACK2) == null) {
            RejectedExecutionHandler handler=tp.getThreadPool().getRejectedExecutionHandler();
            if(handler != null && !isCallerRunsHandler(handler)) {
                log.warn("the absence of %s or %s requires CallerRunsPolicy in the thread pool; replacing %s",
                         UNICAST3.getSimpleName(), NAKACK2.getSimpleName(),
                         handler.getClass().getSimpleName());
                tp.getThreadPool().setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
            }
        }
    }

    protected static boolean isCallerRunsHandler(RejectedExecutionHandler h) {
        return h instanceof ThreadPoolExecutor.CallerRunsPolicy ||
          (h instanceof ShutdownRejectedExecutionHandler
            && ((ShutdownRejectedExecutionHandler)h).handler() instanceof ThreadPoolExecutor.CallerRunsPolicy);
    }
}