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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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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 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/**
 * 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);
        provider.init();
        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
                }
            }
        }
    }
}