/*

 */

package sun.tracing;

import java.lang.reflect.Method;

import java.lang.reflect.InvocationTargetException;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Set;

import java.util.logging.Logger;

import com.sun.tracing.ProviderFactory;

import com.sun.tracing.Provider;

import com.sun.tracing.Probe;

/**

 * Factory class to create tracing Providers.

 *

 * This factory creates a "multiplex provider", which is a provider that

 * encapsulates a list of providers and whose probes trigger a corresponding

 * trigger in each of the encapsulated providers' probes.

 *

 * This is used when there are multiple tracing frameworks activated at once.

 * A user-defined provider gets implementation for each of the activated

 * frameworks and this multiplex framework is what is ultimately passed

 * back to the user.  All probe triggers are multiplexed to each

 * active framework.

 *

 * @since 1.7

 */

public class MultiplexProviderFactory extends ProviderFactory {

    private Set<ProviderFactory> factories;

    public MultiplexProviderFactory(Set<ProviderFactory> factories) {

        this.factories = factories;

    }

    public <T extends Provider> T createProvider(Class<T> cls) {

        HashSet<Provider> providers = new HashSet<Provider>();

        for (ProviderFactory factory : factories) {

            providers.add(factory.createProvider(cls));

        }

        MultiplexProvider provider = new MultiplexProvider(cls, providers);

        try {

            provider.init();

        } catch (Exception e) {

            // Probably a permission problem (can't get declared members)

            Logger.getAnonymousLogger().warning(

                "Could not initialize tracing provider: " + e.getMessage());

        }

        return provider.newProxyInstance();

    }

}

class MultiplexProvider extends ProviderSkeleton {

    private Set<Provider> providers;

    protected ProbeSkeleton createProbe(Method m) {

        return new MultiplexProbe(m, providers);

    }

    MultiplexProvider(Class<? extends Provider> type, Set<Provider> providers) {

        super(type);

        this.providers = providers;

    }

    public void dispose() {

        for (Provider p : providers) {

            p.dispose();

        }

        super.dispose();

    }

}

class MultiplexProbe extends ProbeSkeleton {

    private Set<Probe> probes;

    MultiplexProbe(Method m, Set<Provider> providers) {

        super(m.getParameterTypes());

        probes = new HashSet<Probe>();

        for (Provider p : providers) {

            Probe probe = p.getProbe(m);

            if (probe != null) {

                probes.add(probe);

            }

        }

    }

    public boolean isEnabled() {

        for (Probe p : probes) {

            if (p.isEnabled()) {

                return true;

            }

        }

        return false;

    }

    public void uncheckedTrigger(Object[] args) {

        for (Probe p : probes) {

            try {

                // try the fast path

                ProbeSkeleton ps = (ProbeSkeleton)p;

                ps.uncheckedTrigger(args);

            } catch (ClassCastException e) {

                // Probe.trigger takes an "Object ..." varargs parameter,

                // so we can't call it directly.

                try {

                    Method m = Probe.class.getMethod(

                        "trigger", Class.forName("[java.lang.Object"));

                    m.invoke(p, args);

                } catch (Exception e1) {

                    assert false; // This shouldn't happen

                }

            }

        }

    }

}