org.drools.examples.twittercbr.TwitterCBR.java Source code

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Here is the source code for org.drools.examples.twittercbr.TwitterCBR.java

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/*
 * Copyright 2011 JBoss 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 org.drools.examples.twittercbr;

import java.io.IOException;

import org.drools.ClockType;
import org.drools.KnowledgeBase;
import org.drools.KnowledgeBaseConfiguration;
import org.drools.KnowledgeBaseFactory;
import org.drools.builder.KnowledgeBuilder;
import org.drools.builder.KnowledgeBuilderFactory;
import org.drools.builder.ResourceType;
import org.drools.conf.EventProcessingOption;
import org.drools.io.ResourceFactory;
import org.drools.runtime.KnowledgeSessionConfiguration;
import org.drools.runtime.StatefulKnowledgeSession;
import org.drools.runtime.conf.ClockTypeOption;
import org.drools.runtime.rule.WorkingMemoryEntryPoint;

import twitter4j.StatusListener;
import twitter4j.TwitterException;
import twitter4j.TwitterStream;
import twitter4j.TwitterStreamFactory;

/**
 * TwitterCBR
 */
public class TwitterCBR {
    public static final boolean disableLog = true;

    /**
     * Main method
     */
    public static void main(String[] args) throws TwitterException, IOException {
        if (args.length == 0) {
            System.out.println("Please provide the rules file name to load.");
            System.exit(0);
        }

        // Creates a knowledge base
        final KnowledgeBase kbase = createKnowledgeBase(args[0]);

        // Creates a knowledge session
        final StatefulKnowledgeSession ksession = createKnowledgeSession(kbase);

        // Gets the stream entry point 
        final WorkingMemoryEntryPoint ep = ksession.getWorkingMemoryEntryPoint("twitter");

        // Connects to the twitter stream and register the listener 
        new Thread(new Runnable() {
            @Override
            public void run() {
                StatusListener listener = new TwitterStatusListener(ep);
                TwitterStream twitterStream = new TwitterStreamFactory().getInstance();
                twitterStream.addListener(listener);
                twitterStream.sample();
            }
        }).start();

        // Starts to fire rules in Drools Fusion
        ksession.fireUntilHalt();
    }

    /**
     * Creates a Drools KnowledgeBase and adds the given rules file into it
     */
    private static KnowledgeBase createKnowledgeBase(final String rulesFile) {
        // Parses and compiles the rules file
        KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
        kbuilder.add(ResourceFactory.newClassPathResource(rulesFile), ResourceType.DRL);

        // Configures the Stream mode
        KnowledgeBaseConfiguration conf = KnowledgeBaseFactory.newKnowledgeBaseConfiguration();
        conf.setOption(EventProcessingOption.STREAM);

        // Creates the knowledge base and adds the rules
        KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase(conf);
        kbase.addKnowledgePackages(kbuilder.getKnowledgePackages());
        return kbase;
    }

    /**
     * Creates a Drools Stateful Knowledge Session
     */
    private static StatefulKnowledgeSession createKnowledgeSession(final KnowledgeBase kbase) {
        final KnowledgeSessionConfiguration ksconf = KnowledgeBaseFactory.newKnowledgeSessionConfiguration();
        ksconf.setOption(ClockTypeOption.get(ClockType.REALTIME_CLOCK.getId()));
        final StatefulKnowledgeSession ksession = kbase.newStatefulKnowledgeSession(ksconf, null);
        return ksession;
    }

    static {
        // disable twitter4j log
        System.setProperty("twitter4j.loggerFactory", "twitter4j.internal.logging.NullLoggerFactory");
    }

}