* Implementations should be thread-safe.
 */
@ThreadSafe
@ServiceScope(Scope.Global.class)
public interface DaemonRegistry {

    List<DaemonInfo> getAll();
    List<DaemonInfo> getIdle();
    List<DaemonInfo> getNotIdle();
    List<DaemonInfo> getCanceled();

    void store(DaemonInfo info);
    void remove(Address address);
    void markState(Address address, State state);

    void storeStopEvent(DaemonStopEvent stopEvent);

        return daemonInfosOfEntriesMatching(allSpec);
    }

    public List<DaemonInfo> getIdle() {
        return daemonInfosOfEntriesMatching(idleSpec);
    }

    public List<DaemonInfo> getNotIdle() {
        return daemonInfosOfEntriesMatching(busySpec);
    }

    public List<DaemonInfo> getCanceled() {
        return daemonInfosOfEntriesMatching(canceledSpec);
    }

    @Override

            public boolean isSatisfiedBy(DaemonInfo daemonInfo) {
                return daemonInfo.getState() == Idle;
            }
        });
    }

    @Override
    public List<DaemonInfo> getNotIdle() {
        return getDaemonsMatching(new Spec<DaemonInfo>() {
            @Override
            public boolean isSatisfiedBy(DaemonInfo daemonInfo) {
                return daemonInfo.getState() != Idle;
            }

        // Look for 'our' daemon among the busy daemons - a daemon will start in busy state so that nobody else will grab it.
        for (DaemonInfo daemonInfo : daemonRegistry.getNotIdle()) {
            if (daemonInfo.getUid().equals(daemon.getUid())) {
                try {
                    if (!constraint.isSatisfiedBy(daemonInfo.getContext())) {