com.jgoetsch.eventtrader.EventTraderSpringLauncher.java Source code

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Here is the source code for com.jgoetsch.eventtrader.EventTraderSpringLauncher.java

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/*
 * Copyright (c) 2012 Jeremy Goetsch
 *
 * 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 com.jgoetsch.eventtrader;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.BeanFactoryUtils;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
 * A simple launcher class with a main method to launch EventTrader apps defined in
 * Spring bean xml files.
 * 
 * @author jgoetsch
 *
 */
public class EventTraderSpringLauncher {
    private static Logger log = LoggerFactory.getLogger(EventTraderSpringLauncher.class);

    public static void main(String[] args) {
        if (args.length < 1) {
            System.out.println("Usage: " + EventTraderSpringLauncher.class.getSimpleName() + " <files>...");
            System.out.println("       files - List of paths to spring bean definition xml files.");
            System.out.println("               Each object defined that implements Runnable will be executed");
            System.out.println("               in its own thread.");
        } else {
            AbstractApplicationContext context = new ClassPathXmlApplicationContext(args);

            // auto register growl notifications after all GrowlNotification objects have been instantiated
            // if it is found on the classpath
            try {
                Class.forName("com.jgoetsch.eventtrader.processor.GrowlNotification").getMethod("autoRegister")
                        .invoke(null);
            } catch (Exception e) {
                log.warn("Growl not found, cannot autoRegister notifications: {}", e.getMessage());
            }

            Map<String, Runnable> runnables = BeanFactoryUtils.beansOfTypeIncludingAncestors(context,
                    Runnable.class);
            List<Thread> threads = new ArrayList<Thread>(runnables.size());
            for (final Map.Entry<String, Runnable> runner : runnables.entrySet()) {
                final Thread th = new Thread(runner.getValue(), runner.getKey());
                threads.add(th);
                th.start();
            }

            // close spring context on JVM shutdown
            // this causes all @PreDestroy methods in the runnables to be called to allow for
            // them to shutdown gracefully
            context.registerShutdownHook();

            // wait for launched threads to finish before cleaning up beans
            for (Thread th : threads) {
                try {
                    th.join();
                } catch (InterruptedException e) {
                }
            }
        }
    }

}