co.cask.cdap.internal.app.runtime.ProgramControllerServiceAdapter.java Source code

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Here is the source code for co.cask.cdap.internal.app.runtime.ProgramControllerServiceAdapter.java

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/*
 * Copyright  2014 Cask Data, Inc.
 *
 * 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 co.cask.cdap.internal.app.runtime;

import co.cask.cdap.app.runtime.ProgramController;
import com.google.common.util.concurrent.Service;
import org.apache.twill.api.RunId;
import org.apache.twill.common.Threads;
import org.apache.twill.internal.ServiceListenerAdapter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * A {@link ProgramController} implementation that control a guava Service.
 */
public class ProgramControllerServiceAdapter extends AbstractProgramController {

    private static final Logger LOG = LoggerFactory.getLogger(ProgramControllerServiceAdapter.class);

    private final Service service;

    public ProgramControllerServiceAdapter(Service service, String programName, RunId runId) {
        super(programName, runId);
        this.service = service;
        listenToRuntimeState(service);
    }

    @Override
    protected void doSuspend() throws Exception {

    }

    @Override
    protected void doResume() throws Exception {

    }

    @Override
    protected void doStop() throws Exception {
        if (service.state() != Service.State.TERMINATED && service.state() != Service.State.FAILED) {
            service.stopAndWait();
        }
    }

    @Override
    protected void doCommand(String name, Object value) throws Exception {

    }

    private void listenToRuntimeState(Service service) {
        service.addListener(new ServiceListenerAdapter() {
            @Override
            public void running() {
                started();
            }

            @Override
            public void failed(Service.State from, Throwable failure) {
                LOG.error("Program terminated with exception", failure);
                error(failure);
            }

            @Override
            public void terminated(Service.State from) {
                if (from != Service.State.STOPPING) {
                    // Service completed by itself. Simply signal the state change of this controller.
                    complete();
                } else {
                    // Service was killed
                    stop();
                }
            }
        }, Threads.SAME_THREAD_EXECUTOR);
    }
}