【Esper技术专题】一个简单的事件响应功能的案例（2）复杂事件处理引擎

public class PersonEvent extends Event {
    private String name;
    private int age;
    public PersonEvent(String name, int age) {
        this.name = name;
        this.age = age;
    }
    public String getName() {
        return name;
    }
    public int getAge() {
        return age;
    }    
}
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import com.espertech.esper.client.EPServiceProvider;
import com.espertech.esper.client.EPServiceProviderManager;
import com.espertech.esper.client.EPStatement;
import com.events.Event;
import com.events.OrderEvent;
import com.events.PersonEvent;
import com.listener.OrderEventListener;
import com.listener.PersonEventListener;
public class EsperClient {
    private EPServiceProvider engine;
    public EsperClient() {
        //obtain an engine instance
        this.engine = EPServiceProviderManager.getDefaultProvider();
        //System.out.println(engine.getURI());
    }
    public void personEventProcess() {
        //tell the engine about the event type
        engine.getEPAdministrator().getConfiguration().addEventType(PersonEvent.class);
        //create an epl statement
        String epl = "select name, age from PersonEvent";
        EPStatement statement = engine.getEPAdministrator().createEPL(epl);
    }
    public void send(Event event) {
        engine.getEPRuntime().sendEvent(event);
    }
}
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import com.espertech.esper.client.EventBean;
import com.espertech.esper.client.UpdateListener;
public class PersonEventListener implements UpdateListener {
    @Override
    public void update(EventBean[] newEvents, EventBean[] oldEvents) {
        // TODO Auto-generated method stub
        EventBean event = newEvents[0];
        System.out.println(String.format("Name: %s, Age: %d", event.get("name"), event.get("age")));
    }
}
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public void personEventProcess() {
        //tell the engine about the event type
        engine.getEPAdministrator().getConfiguration().
        addEventType(PersonEvent.class);
        //create an epl statement
        String epl = "select avg(age) from PersonEvent";
        EPStatement statement = engine.getEPAdministrator().createEPL(epl);
        //attach a callback to receive the results
        statement.addListener(new PersonEventListener());
    }
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import com.esper.client.EsperClient;
import com.events.PersonEvent;
public class Test {
    @SuppressWarnings("static-access")
    public static void main(String[] args) throws InterruptedException {
        // TODO Auto-generated method stub
        EsperClient ec = new EsperClient();
        ec.personEventProcess();
        ec.send(new PersonEvent("name", 10));    
        ec.send(new PersonEvent("name", 20));    
   }
}
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