com.rabbitmq.jms.sample.StockQuoter.java Source code

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Here is the source code for com.rabbitmq.jms.sample.StockQuoter.java

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/*
 * Copyright (C) 2007-2016 Pivotal Software 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 com.rabbitmq.jms.sample;

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

import javax.jms.ConnectionFactory;
import javax.jms.Session;

import org.apache.commons.lang.math.RandomUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.jms.core.JmsTemplate;
import org.springframework.jms.core.MessageCreator;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;

import com.rabbitmq.jms.admin.RMQConnectionFactory;

@SpringBootApplication
@EnableScheduling
public class StockQuoter {

    private static final Log log = LogFactory.getLog(StockQuoter.class);

    private List<String> stocks = new ArrayList<String>();
    private Map<String, Double> lastPrice = new HashMap<String, Double>();

    {
        stocks.add("AAPL");
        stocks.add("GD");
        stocks.add("BRK.B");

        lastPrice.put("AAPL", 494.64);
        lastPrice.put("GD", 86.74);
        lastPrice.put("BRK.B", 113.59);
    }

    @Autowired
    JmsTemplate jmsTemplate;

    @Bean
    ConnectionFactory connectionFactory() {
        return new RMQConnectionFactory();
    }

    @Scheduled(fixedRate = 5000L) // every 5 seconds
    public void publishQuote() {

        // Pick a random stock symbol
        Collections.shuffle(stocks);
        String symbol = stocks.get(0);

        // Toss a coin and decide if the price goes...
        if (RandomUtils.nextBoolean()) {
            // ...up by a random 0-10%
            lastPrice.put(symbol, new Double(
                    Math.round(lastPrice.get(symbol) * (1 + RandomUtils.nextInt(10) / 100.0) * 100) / 100));
        } else {
            // ...or down by a similar random amount
            lastPrice.put(symbol, new Double(
                    Math.round(lastPrice.get(symbol) * (1 - RandomUtils.nextInt(10) / 100.0) * 100) / 100));
        }

        // Log new price locally
        log.info("Quote..." + symbol + " is now " + lastPrice.get(symbol));

        // Coerce a javax.jms.MessageCreator
        MessageCreator messageCreator = (Session session) -> {
            return session.createObjectMessage("Quote..." + symbol + " is now " + lastPrice.get(symbol));
        };

        // And publish to RabbitMQ using Spring's JmsTemplate
        jmsTemplate.send("rabbit-trader-channel", messageCreator);
    }

    public static void main(String[] args) {
        SpringApplication.run(StockQuoter.class, args);
    }

}