Resolves checkstyle errors for event-* (#1070)
* Reduces checkstyle errors in event-aggregator * Reduces checkstyle errors in event-asynchronous * Reduces checkstyle errors in event-driven-architecture * Reduces checkstyle errors in event-queue * Reduces checkstyle errors in event-sourcing
This commit is contained in:
Anurag Agarwal
Ilkka Seppälä
parent
7c888e8886
commit
5ae2ce6e2e
@ -27,23 +27,21 @@ import java.util.ArrayList;
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import java.util.List;
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/**
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*
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* A system with lots of objects can lead to complexities when a client wants to subscribe to
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* events. The client has to find and register for each object individually, if each object has
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* multiple events then each event requires a separate subscription.
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* <p>
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* An Event Aggregator acts as a single source of events for many objects. It registers for all the
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* events of the many objects allowing clients to register with just the aggregator.
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* <p>
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* In the example {@link LordBaelish}, {@link LordVarys} and {@link Scout} deliver events to
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* {@link KingsHand}. {@link KingsHand}, the event aggregator, then delivers the events to
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* {@link KingJoffrey}.
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*
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* <p>An Event Aggregator acts as a single source of events for many objects. It registers for all
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* the events of the many objects allowing clients to register with just the aggregator.
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*
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* <p>In the example {@link LordBaelish}, {@link LordVarys} and {@link Scout} deliver events to
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* {@link KingsHand}. {@link KingsHand}, the event aggregator, then delivers the events to {@link
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* KingJoffrey}.
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*/
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public class App {
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/**
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* Program entry point
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* Program entry point.
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*
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* @param args command line args
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*/
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@ -24,9 +24,7 @@
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package com.iluwatar.event.aggregator;
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/**
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*
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* Event enumeration.
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*
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*/
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public enum Event {
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@ -27,9 +27,7 @@ import java.util.LinkedList;
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import java.util.List;
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/**
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*
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* EventEmitter is the base class for event producers that can be observed.
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*
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*/
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public abstract class EventEmitter {
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@ -24,9 +24,7 @@
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package com.iluwatar.event.aggregator;
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/**
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*
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* Observers of events implement this interface.
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*
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*/
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public interface EventObserver {
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@ -27,9 +27,7 @@ import org.slf4j.Logger;
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import org.slf4j.LoggerFactory;
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/**
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*
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* KingJoffrey observes events from {@link KingsHand}.
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*
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*/
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public class KingJoffrey implements EventObserver {
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@ -24,9 +24,7 @@
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package com.iluwatar.event.aggregator;
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/**
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*
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* KingsHand observes events from multiple sources and delivers them to listeners.
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*
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*/
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public class KingsHand extends EventEmitter implements EventObserver {
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@ -24,9 +24,7 @@
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package com.iluwatar.event.aggregator;
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/**
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*
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* LordBaelish produces events.
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*
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*/
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public class LordBaelish extends EventEmitter {
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@ -24,9 +24,7 @@
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package com.iluwatar.event.aggregator;
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/**
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*
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* LordVarys produces events.
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*
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*/
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public class LordVarys extends EventEmitter {
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@ -24,9 +24,7 @@
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package com.iluwatar.event.aggregator;
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/**
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*
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* Scout produces events.
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*
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*/
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public class Scout extends EventEmitter {
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@ -24,9 +24,7 @@
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package com.iluwatar.event.aggregator;
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/**
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*
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* Weekday enumeration
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*
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* Weekday enumeration.
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*/
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public enum Weekday {
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@ -23,38 +23,38 @@
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package com.iluwatar.event.asynchronous;
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import org.slf4j.Logger;
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import org.slf4j.LoggerFactory;
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import java.io.IOException;
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import java.io.InputStream;
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import java.util.Properties;
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import java.util.Scanner;
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import org.slf4j.Logger;
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import org.slf4j.LoggerFactory;
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/**
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* This application demonstrates the <b>Event-based Asynchronous</b> pattern. Essentially, users (of
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* the pattern) may choose to run events in an Asynchronous or Synchronous mode. There can be
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* multiple Asynchronous events running at once but only one Synchronous event can run at a time.
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* Asynchronous events are synonymous to multi-threads. The key point here is that the threads run
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* in the background and the user is free to carry on with other processes. Once an event is
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* complete, the appropriate listener/callback method will be called. The listener then proceeds to
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* carry out further processing depending on the needs of the user.
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*
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* This application demonstrates the <b>Event-based Asynchronous</b> pattern. Essentially, users (of the pattern) may
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* choose to run events in an Asynchronous or Synchronous mode. There can be multiple Asynchronous events running at
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* once but only one Synchronous event can run at a time. Asynchronous events are synonymous to multi-threads. The key
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* point here is that the threads run in the background and the user is free to carry on with other processes. Once an
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* event is complete, the appropriate listener/callback method will be called. The listener then proceeds to carry out
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* further processing depending on the needs of the user.
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* <p>The {@link EventManager} manages the events/threads that the user creates. Currently, the
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* supported event operations are: <code>start</code>, <code>stop</code>, <code>getStatus</code>.
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* For Synchronous events, the user is unable to start another (Synchronous) event if one is already
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* running at the time. The running event would have to either be stopped or completed before a new
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* event can be started.
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*
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* The {@link EventManager} manages the events/threads that the user creates. Currently, the supported event operations
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* are: <code>start</code>, <code>stop</code>, <code>getStatus</code>. For Synchronous events, the user is unable to
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* start another (Synchronous) event if one is already running at the time. The running event would have to either be
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* stopped or completed before a new event can be started.
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*
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* The Event-based Asynchronous Pattern makes available the advantages of multithreaded applications while hiding many
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* of the complex issues inherent in multithreaded design. Using a class that supports this pattern can allow you to:-
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* (1) Perform time-consuming tasks, such as downloads and database operations, "in the background," without
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* interrupting your application. (2) Execute multiple operations simultaneously, receiving notifications when each
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* completes. (3) Wait for resources to become available without stopping ("hanging") your application. (4) Communicate
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* with pending asynchronous operations using the familiar events-and-delegates model.
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* <p>The Event-based Asynchronous Pattern makes available the advantages of multithreaded
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* applications while hiding many of the complex issues inherent in multithreaded design. Using a
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* class that supports this pattern can allow you to:- (1) Perform time-consuming tasks, such as
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* downloads and database operations, "in the background," without interrupting your application.
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* (2) Execute multiple operations simultaneously, receiving notifications when each completes. (3)
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* Wait for resources to become available without stopping ("hanging") your application. (4)
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* Communicate with pending asynchronous operations using the familiar events-and-delegates model.
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*
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* @see EventManager
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* @see Event
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*
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*/
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public class App {
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@ -67,8 +67,7 @@ public class App {
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/**
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* Program entry point.
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*
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* @param args
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* command line args
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* @param args command line args
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*/
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public static void main(String[] args) {
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App app = new App();
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@ -78,8 +77,9 @@ public class App {
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}
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/**
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* App can run in interactive mode or not. Interactive mode == Allow user interaction with command line.
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* Non-interactive is a quick sequential run through the available {@link EventManager} operations.
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* App can run in interactive mode or not. Interactive mode == Allow user interaction with command
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* line. Non-interactive is a quick sequential run through the available {@link EventManager}
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* operations.
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*/
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public void setUp() {
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Properties prop = new Properties();
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@ -118,24 +118,24 @@ public class App {
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try {
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// Create an Asynchronous event.
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int aEventId = eventManager.createAsync(60);
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LOGGER.info("Async Event [{}] has been created.", aEventId);
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eventManager.start(aEventId);
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LOGGER.info("Async Event [{}] has been started.", aEventId);
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int asyncEventId = eventManager.createAsync(60);
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LOGGER.info("Async Event [{}] has been created.", asyncEventId);
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eventManager.start(asyncEventId);
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LOGGER.info("Async Event [{}] has been started.", asyncEventId);
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// Create a Synchronous event.
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int sEventId = eventManager.create(60);
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LOGGER.info("Sync Event [{}] has been created.", sEventId);
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eventManager.start(sEventId);
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LOGGER.info("Sync Event [{}] has been started.", sEventId);
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int syncEventId = eventManager.create(60);
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LOGGER.info("Sync Event [{}] has been created.", syncEventId);
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eventManager.start(syncEventId);
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LOGGER.info("Sync Event [{}] has been started.", syncEventId);
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eventManager.status(aEventId);
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eventManager.status(sEventId);
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eventManager.status(asyncEventId);
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eventManager.status(syncEventId);
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eventManager.cancel(aEventId);
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LOGGER.info("Async Event [{}] has been stopped.", aEventId);
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eventManager.cancel(sEventId);
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LOGGER.info("Sync Event [{}] has been stopped.", sEventId);
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eventManager.cancel(asyncEventId);
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LOGGER.info("Async Event [{}] has been stopped.", asyncEventId);
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eventManager.cancel(syncEventId);
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LOGGER.info("Sync Event [{}] has been stopped.", syncEventId);
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} catch (MaxNumOfEventsAllowedException | LongRunningEventException | EventDoesNotExistException
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| InvalidOperationException e) {
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@ -211,7 +211,8 @@ public class App {
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int eventId = eventManager.createAsync(eventTime);
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eventManager.start(eventId);
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LOGGER.info("Egg [{}] is being boiled.", eventId);
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} catch (MaxNumOfEventsAllowedException | LongRunningEventException | EventDoesNotExistException e) {
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} catch (MaxNumOfEventsAllowedException | LongRunningEventException
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| EventDoesNotExistException e) {
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LOGGER.error(e.getMessage());
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}
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} else if (eventType.equalsIgnoreCase("S")) {
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@ -219,8 +220,8 @@ public class App {
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int eventId = eventManager.create(eventTime);
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eventManager.start(eventId);
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LOGGER.info("Egg [{}] is being boiled.", eventId);
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} catch (MaxNumOfEventsAllowedException | InvalidOperationException | LongRunningEventException
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| EventDoesNotExistException e) {
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} catch (MaxNumOfEventsAllowedException | InvalidOperationException
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| LongRunningEventException | EventDoesNotExistException e) {
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LOGGER.error(e.getMessage());
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}
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} else {
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@ -27,9 +27,7 @@ import org.slf4j.Logger;
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import org.slf4j.LoggerFactory;
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/**
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*
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* Each Event runs as a separate/individual thread.
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*
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*/
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public class Event implements IEvent, Runnable {
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@ -43,6 +41,7 @@ public class Event implements IEvent, Runnable {
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private ThreadCompleteListener eventListener;
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/**
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* Constructor.
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*
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* @param eventId event ID
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* @param eventTime event time
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@ -24,7 +24,7 @@
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package com.iluwatar.event.asynchronous;
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/**
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* Custom Exception Class for Non Existent Event
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* Custom Exception Class for Non Existent Event.
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*/
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public class EventDoesNotExistException extends Exception {
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@ -29,17 +29,17 @@ import java.util.Random;
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import java.util.concurrent.ConcurrentHashMap;
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/**
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*
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* EventManager handles and maintains a pool of event threads. {@link Event} threads are created upon user request. Thre
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* are two types of events; Asynchronous and Synchronous. There can be multiple Asynchronous events running at once but
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* only one Synchronous event running at a time. Currently supported event operations are: start, stop, and getStatus.
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* Once an event is complete, it then notifies EventManager through a listener. The EventManager then takes the event
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* out of the pool.
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*
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* EventManager handles and maintains a pool of event threads. {@link Event} threads are created
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* upon user request. Thre are two types of events; Asynchronous and Synchronous. There can be
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* multiple Asynchronous events running at once but only one Synchronous event running at a time.
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* Currently supported event operations are: start, stop, and getStatus. Once an event is complete,
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* it then notifies EventManager through a listener. The EventManager then takes the event out of
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* the pool.
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*/
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public class EventManager implements ThreadCompleteListener {
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public static final int MAX_RUNNING_EVENTS = 1000; // Just don't wanna have too many running events. :)
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public static final int MAX_RUNNING_EVENTS = 1000;
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// Just don't wanna have too many running events. :)
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public static final int MIN_ID = 1;
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public static final int MAX_ID = MAX_RUNNING_EVENTS;
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public static final int MAX_EVENT_TIME = 1800; // in seconds / 30 minutes.
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@ -51,7 +51,6 @@ public class EventManager implements ThreadCompleteListener {
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/**
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* EventManager constructor.
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*
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*/
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public EventManager() {
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rand = new Random(1);
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@ -65,14 +64,15 @@ public class EventManager implements ThreadCompleteListener {
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* @param eventTime Time an event should run for.
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* @return eventId
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* @throws MaxNumOfEventsAllowedException When too many events are running at a time.
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* @throws InvalidOperationException No new synchronous events can be created when one is already running.
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* @throws InvalidOperationException No new synchronous events can be created when one is
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* already running.
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* @throws LongRunningEventException Long running events are not allowed in the app.
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*/
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public int create(int eventTime)
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throws MaxNumOfEventsAllowedException, InvalidOperationException, LongRunningEventException {
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if (currentlyRunningSyncEvent != -1) {
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throw new InvalidOperationException(
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"Event [" + currentlyRunningSyncEvent + "] is still running. Please wait until it finishes and try again.");
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throw new InvalidOperationException("Event [" + currentlyRunningSyncEvent + "] is still"
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+ " running. Please wait until it finishes and try again.");
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}
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int eventId = createEvent(eventTime, true);
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@ -89,14 +89,16 @@ public class EventManager implements ThreadCompleteListener {
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* @throws MaxNumOfEventsAllowedException When too many events are running at a time.
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* @throws LongRunningEventException Long running events are not allowed in the app.
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*/
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public int createAsync(int eventTime) throws MaxNumOfEventsAllowedException, LongRunningEventException {
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public int createAsync(int eventTime) throws MaxNumOfEventsAllowedException,
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LongRunningEventException {
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return createEvent(eventTime, false);
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}
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private int createEvent(int eventTime, boolean isSynchronous)
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throws MaxNumOfEventsAllowedException, LongRunningEventException {
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if (eventPool.size() == MAX_RUNNING_EVENTS) {
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throw new MaxNumOfEventsAllowedException("Too many events are running at the moment. Please try again later.");
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throw new MaxNumOfEventsAllowedException("Too many events are running at the moment."
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+ " Please try again later.");
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}
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if (eventTime >= MAX_EVENT_TIME) {
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@ -185,7 +187,8 @@ public class EventManager implements ThreadCompleteListener {
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}
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/**
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* Returns a pseudo-random number between min and max, inclusive. The difference between min and max can be at most
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* Returns a pseudo-random number between min and max, inclusive. The difference between min and
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* max can be at most
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* <code>Integer.MAX_VALUE - 1</code>.
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*/
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private int generateId() {
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@ -24,8 +24,7 @@
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package com.iluwatar.event.asynchronous;
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/**
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* Events that fulfill the start stop and list out current status behaviour
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* follow this interface
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* Events that fulfill the start stop and list out current status behaviour follow this interface.
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*/
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public interface IEvent {
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@ -24,7 +24,7 @@
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package com.iluwatar.event.asynchronous;
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/**
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* Type of Exception raised when the Operation being invoked is Invalid
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* Type of Exception raised when the Operation being invoked is Invalid.
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*/
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public class InvalidOperationException extends Exception {
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@ -24,7 +24,7 @@
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package com.iluwatar.event.asynchronous;
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/**
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* Type of Exception raised when the Operation being invoked is Long Running
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* Type of Exception raised when the Operation being invoked is Long Running.
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*/
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public class LongRunningEventException extends Exception {
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@ -24,7 +24,7 @@
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package com.iluwatar.event.asynchronous;
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/**
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* Type of Exception raised when the max number of allowed events is exceeded
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* Type of Exception raised when the max number of allowed events is exceeded.
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*/
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public class MaxNumOfEventsAllowedException extends Exception {
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@ -34,11 +34,11 @@ import com.iluwatar.eda.model.User;
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/**
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* An event-driven architecture (EDA) is a framework that orchestrates behavior around the
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* production, detection and consumption of events as well as the responses they evoke. An event is
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* any identifiable occurrence that has significance for system hardware or software. <p> The
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* example below uses an {@link EventDispatcher} to link/register {@link Event} objects to their
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* respective handlers once an {@link Event} is dispatched, it's respective handler is invoked and
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* the {@link Event} is handled accordingly.
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* any identifiable occurrence that has significance for system hardware or software.
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*
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* <p>The example below uses an {@link EventDispatcher} to link/register {@link Event} objects to
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* their respective handlers once an {@link Event} is dispatched, it's respective handler is invoked
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* and the {@link Event} is handled accordingly.
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*/
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public class App {
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@ -47,9 +47,8 @@ public class App {
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* made known to the dispatcher by registering them. In this case the {@link UserCreatedEvent} is
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* bound to the UserCreatedEventHandler, whilst the {@link UserUpdatedEvent} is bound to the
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* {@link UserUpdatedEventHandler}. The dispatcher can now be called to dispatch specific events.
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* When a user is saved, the {@link UserCreatedEvent} can be dispatched.
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* On the other hand, when a user is updated, {@link UserUpdatedEvent} can be dispatched.
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*
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* When a user is saved, the {@link UserCreatedEvent} can be dispatched. On the other hand, when a
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* user is updated, {@link UserUpdatedEvent} can be dispatched.
|
||||
*/
|
||||
public static void main(String[] args) {
|
||||
|
||||
|
||||
@ -23,12 +23,12 @@
|
||||
|
||||
package com.iluwatar.eda.event;
|
||||
|
||||
import com.iluwatar.eda.framework.EventDispatcher;
|
||||
import com.iluwatar.eda.framework.Event;
|
||||
import com.iluwatar.eda.framework.EventDispatcher;
|
||||
|
||||
/**
|
||||
* The {@link AbstractEvent} class serves as a base class for defining custom events happening with your
|
||||
* system. In this example we have two types of events defined.
|
||||
* The {@link AbstractEvent} class serves as a base class for defining custom events happening with
|
||||
* your system. In this example we have two types of events defined.
|
||||
* <ul>
|
||||
* <li>{@link UserCreatedEvent} - used when a user is created</li>
|
||||
* <li>{@link UserUpdatedEvent} - used when a user is updated</li>
|
||||
@ -38,9 +38,8 @@ import com.iluwatar.eda.framework.Event;
|
||||
public abstract class AbstractEvent implements Event {
|
||||
|
||||
/**
|
||||
* Returns the event type as a {@link Class} object
|
||||
* In this example, this method is used by the {@link EventDispatcher} to
|
||||
* dispatch events depending on their type.
|
||||
* Returns the event type as a {@link Class} object In this example, this method is used by the
|
||||
* {@link EventDispatcher} to dispatch events depending on their type.
|
||||
*
|
||||
* @return the AbstractEvent type as a {@link Class}.
|
||||
*/
|
||||
|
||||
@ -26,9 +26,9 @@ package com.iluwatar.eda.event;
|
||||
import com.iluwatar.eda.model.User;
|
||||
|
||||
/**
|
||||
* The {@link UserCreatedEvent} should should be dispatched whenever a user has been created.
|
||||
* This class can be extended to contain details about the user has been created. In this example,
|
||||
* the entire {@link User} object is passed on as data with the event.
|
||||
* The {@link UserCreatedEvent} should should be dispatched whenever a user has been created. This
|
||||
* class can be extended to contain details about the user has been created. In this example, the
|
||||
* entire {@link User} object is passed on as data with the event.
|
||||
*/
|
||||
public class UserCreatedEvent extends AbstractEvent {
|
||||
|
||||
|
||||
@ -26,9 +26,9 @@ package com.iluwatar.eda.event;
|
||||
import com.iluwatar.eda.model.User;
|
||||
|
||||
/**
|
||||
* The {@link UserUpdatedEvent} should should be dispatched whenever a user has been updated.
|
||||
* This class can be extended to contain details about the user has been updated. In this example,
|
||||
* the entire {@link User} object is passed on as data with the event.
|
||||
* The {@link UserUpdatedEvent} should should be dispatched whenever a user has been updated. This
|
||||
* class can be extended to contain details about the user has been updated. In this example, the
|
||||
* entire {@link User} object is passed on as data with the event.
|
||||
*/
|
||||
public class UserUpdatedEvent extends AbstractEvent {
|
||||
|
||||
|
||||
@ -24,14 +24,15 @@
|
||||
package com.iluwatar.eda.framework;
|
||||
|
||||
/**
|
||||
* A {@link Event} is an object with a specific type that is associated
|
||||
* to a specific {@link Handler}.
|
||||
* A {@link Event} is an object with a specific type that is associated to a specific {@link
|
||||
* Handler}.
|
||||
*/
|
||||
public interface Event {
|
||||
|
||||
/**
|
||||
* Returns the message type as a {@link Class} object. In this example the message type is
|
||||
* used to handle events by their type.
|
||||
* Returns the message type as a {@link Class} object. In this example the message type is used to
|
||||
* handle events by their type.
|
||||
*
|
||||
* @return the message type as a {@link Class}.
|
||||
*/
|
||||
Class<? extends Event> getType();
|
||||
|
||||
@ -27,8 +27,8 @@ import java.util.HashMap;
|
||||
import java.util.Map;
|
||||
|
||||
/**
|
||||
* Handles the routing of {@link Event} messages to associated handlers.
|
||||
* A {@link HashMap} is used to store the association between events and their respective handlers.
|
||||
* Handles the routing of {@link Event} messages to associated handlers. A {@link HashMap} is used
|
||||
* to store the association between events and their respective handlers.
|
||||
*/
|
||||
public class EventDispatcher {
|
||||
|
||||
|
||||
@ -24,16 +24,18 @@
|
||||
package com.iluwatar.eda.framework;
|
||||
|
||||
/**
|
||||
* This interface can be implemented to handle different types of messages.
|
||||
* Every handler is responsible for a single of type message
|
||||
* This interface can be implemented to handle different types of messages. Every handler is
|
||||
* responsible for a single of type message
|
||||
*
|
||||
* @param <E> Handler can handle events of type E
|
||||
*/
|
||||
public interface Handler<E extends Event> {
|
||||
|
||||
/**
|
||||
* The onEvent method should implement and handle behavior related to the event.
|
||||
* This can be as simple as calling another service to handle the event on publishing the event on
|
||||
* a queue to be consumed by other sub systems.
|
||||
* The onEvent method should implement and handle behavior related to the event. This can be as
|
||||
* simple as calling another service to handle the event on publishing the event on a queue to be
|
||||
* consumed by other sub systems.
|
||||
*
|
||||
* @param event the {@link Event} object to be handled.
|
||||
*/
|
||||
void onEvent(E event);
|
||||
|
||||
@ -27,8 +27,8 @@ import com.iluwatar.eda.event.UserCreatedEvent;
|
||||
import com.iluwatar.eda.event.UserUpdatedEvent;
|
||||
|
||||
/**
|
||||
* This {@link User} class is a basic pojo used to demonstrate user data sent along with
|
||||
* the {@link UserCreatedEvent} and {@link UserUpdatedEvent} events.
|
||||
* This {@link User} class is a basic pojo used to demonstrate user data sent along with the {@link
|
||||
* UserCreatedEvent} and {@link UserUpdatedEvent} events.
|
||||
*/
|
||||
public class User {
|
||||
|
||||
|
||||
@ -23,28 +23,27 @@
|
||||
|
||||
package com.iluwatar.event.queue;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.io.BufferedReader;
|
||||
import java.io.IOException;
|
||||
import java.io.InputStreamReader;
|
||||
|
||||
import javax.sound.sampled.UnsupportedAudioFileException;
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
/**
|
||||
* Event or message queues provide an asynchronous communications protocol, meaning that the sender
|
||||
* and receiver of the message do not need to interact with the message queue at the same time.
|
||||
* Events or messages placed onto the queue are stored until the recipient retrieves them. Event
|
||||
* or message queues have implicit or explicit limits on the size of data that may be transmitted
|
||||
* in a single message and the number of messages that may remain outstanding on the queue.
|
||||
* A queue stores a series of notifications or requests in first-in, first-out order.
|
||||
* Sending a notification enqueues the request and returns. The request processor then processes
|
||||
* items from the queue at a later time.
|
||||
* Events or messages placed onto the queue are stored until the recipient retrieves them. Event or
|
||||
* message queues have implicit or explicit limits on the size of data that may be transmitted in a
|
||||
* single message and the number of messages that may remain outstanding on the queue. A queue
|
||||
* stores a series of notifications or requests in first-in, first-out order. Sending a notification
|
||||
* enqueues the request and returns. The request processor then processes items from the queue at a
|
||||
* later time.
|
||||
*/
|
||||
public class App {
|
||||
|
||||
private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
|
||||
|
||||
/**
|
||||
* Program entry point.
|
||||
*
|
||||
@ -52,7 +51,8 @@ public class App {
|
||||
* @throws IOException when there is a problem with the audio file loading
|
||||
* @throws UnsupportedAudioFileException when the loaded audio file is unsupported
|
||||
*/
|
||||
public static void main(String[] args) throws UnsupportedAudioFileException, IOException, InterruptedException {
|
||||
public static void main(String[] args) throws UnsupportedAudioFileException, IOException,
|
||||
InterruptedException {
|
||||
Audio audio = Audio.getInstance();
|
||||
audio.playSound(audio.getAudioStream("./etc/Bass-Drum-1.wav"), -10.0f);
|
||||
audio.playSound(audio.getAudioStream("./etc/Closed-Hi-Hat-1.wav"), -8.0f);
|
||||
|
||||
@ -23,22 +23,20 @@
|
||||
|
||||
package com.iluwatar.event.queue;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.io.File;
|
||||
import java.io.IOException;
|
||||
|
||||
import javax.sound.sampled.AudioInputStream;
|
||||
import javax.sound.sampled.AudioSystem;
|
||||
import javax.sound.sampled.Clip;
|
||||
import javax.sound.sampled.LineUnavailableException;
|
||||
import javax.sound.sampled.UnsupportedAudioFileException;
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
/**
|
||||
* This class implements the Event Queue pattern.
|
||||
* @author mkuprivecz
|
||||
*
|
||||
* @author mkuprivecz
|
||||
*/
|
||||
public class Audio {
|
||||
private static final Logger LOGGER = LoggerFactory.getLogger(Audio.class);
|
||||
@ -76,6 +74,7 @@ public class Audio {
|
||||
|
||||
/**
|
||||
* This method check the Update Method's thread is started.
|
||||
*
|
||||
* @return boolean
|
||||
*/
|
||||
public synchronized boolean isServiceRunning() {
|
||||
@ -83,8 +82,8 @@ public class Audio {
|
||||
}
|
||||
|
||||
/**
|
||||
* Starts the thread for the Update Method pattern if it was not started previously.
|
||||
* Also when the thread is is ready initializes the indexes of the queue
|
||||
* Starts the thread for the Update Method pattern if it was not started previously. Also when the
|
||||
* thread is is ready initializes the indexes of the queue
|
||||
*/
|
||||
public void init() {
|
||||
if (updateThread == null) {
|
||||
@ -98,7 +97,7 @@ public class Audio {
|
||||
}
|
||||
|
||||
/**
|
||||
* This is a synchronized thread starter
|
||||
* This is a synchronized thread starter.
|
||||
*/
|
||||
private synchronized void startThread() {
|
||||
if (!updateThread.isAlive()) {
|
||||
@ -110,6 +109,7 @@ public class Audio {
|
||||
|
||||
/**
|
||||
* This method adds a new audio into the queue.
|
||||
*
|
||||
* @param stream is the AudioInputStream for the method
|
||||
* @param volume is the level of the audio's volume
|
||||
*/
|
||||
@ -130,8 +130,7 @@ public class Audio {
|
||||
}
|
||||
|
||||
/**
|
||||
* This method uses the Update Method pattern.
|
||||
* It takes the audio from the queue and plays it
|
||||
* This method uses the Update Method pattern. It takes the audio from the queue and plays it
|
||||
*/
|
||||
private void update() {
|
||||
// If there are no pending requests, do nothing.
|
||||
@ -155,7 +154,8 @@ public class Audio {
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the AudioInputStream of a file
|
||||
* Returns the AudioInputStream of a file.
|
||||
*
|
||||
* @param filePath is the path of the audio file
|
||||
* @return AudioInputStream
|
||||
* @throws UnsupportedAudioFileException when the audio file is not supported
|
||||
@ -167,7 +167,8 @@ public class Audio {
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns with the message array of the queue
|
||||
* Returns with the message array of the queue.
|
||||
*
|
||||
* @return PlayMessage[]
|
||||
*/
|
||||
public PlayMessage[] getPendingAudio() {
|
||||
|
||||
@ -27,8 +27,8 @@ import javax.sound.sampled.AudioInputStream;
|
||||
|
||||
/**
|
||||
* The Event Queue's queue will store the instances of this class.
|
||||
* @author mkuprivecz
|
||||
*
|
||||
* @author mkuprivecz
|
||||
*/
|
||||
public class PlayMessage {
|
||||
|
||||
|
||||
@ -42,13 +42,13 @@ import org.slf4j.LoggerFactory;
|
||||
* transactional data, and maintain full audit trails and history that can enable compensating
|
||||
* actions.
|
||||
*
|
||||
* This App class is an example usage of Event Sourcing pattern. As an example, two bank account is
|
||||
* created, then some money deposit and transfer actions are taken so a new state of accounts is
|
||||
* <p>This App class is an example usage of Event Sourcing pattern. As an example, two bank account
|
||||
* is created, then some money deposit and transfer actions are taken so a new state of accounts is
|
||||
* created. At that point, state is cleared in order to represent a system shot down. After the shot
|
||||
* down, system state is recovered by re-creating the past events from event journal. Then state is
|
||||
* printed so a user can view the last state is same with the state before system shot down.
|
||||
*
|
||||
* Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
* <p>Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
*/
|
||||
public class App {
|
||||
|
||||
|
||||
@ -32,11 +32,11 @@ import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
/**
|
||||
* This is the Account class that holds the account info, the account number,
|
||||
* account owner name and money of the account. Account class also have the business logic of events
|
||||
* that effects this account.
|
||||
* This is the Account class that holds the account info, the account number, account owner name and
|
||||
* money of the account. Account class also have the business logic of events that effects this
|
||||
* account.
|
||||
*
|
||||
* Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
* <p>Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
*/
|
||||
public class Account {
|
||||
|
||||
@ -46,7 +46,8 @@ public class Account {
|
||||
private final String owner;
|
||||
private BigDecimal money;
|
||||
|
||||
private static final String MSG = "Some external api for only realtime execution could be called here.";
|
||||
private static final String MSG =
|
||||
"Some external api for only realtime execution could be called here.";
|
||||
|
||||
/**
|
||||
* Instantiates a new Account.
|
||||
|
||||
@ -27,12 +27,11 @@ import com.iluwatar.event.sourcing.domain.Account;
|
||||
import com.iluwatar.event.sourcing.state.AccountAggregate;
|
||||
|
||||
/**
|
||||
* This is the class that implements account create event.
|
||||
* Holds the necessary info for an account create event.
|
||||
* Implements the process function that finds the event related
|
||||
* domain objects and calls the related domain object's handle event functions
|
||||
* This is the class that implements account create event. Holds the necessary info for an account
|
||||
* create event. Implements the process function that finds the event related domain objects and
|
||||
* calls the related domain object's handle event functions
|
||||
*
|
||||
* Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
* <p>Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
*/
|
||||
public class AccountCreateEvent extends DomainEvent {
|
||||
|
||||
|
||||
@ -28,7 +28,7 @@ import java.io.Serializable;
|
||||
/**
|
||||
* This is the base class for domain events. All events must extend this class.
|
||||
*
|
||||
* Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
* <p>Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
*/
|
||||
public abstract class DomainEvent implements Serializable {
|
||||
|
||||
|
||||
@ -28,12 +28,11 @@ import com.iluwatar.event.sourcing.state.AccountAggregate;
|
||||
import java.math.BigDecimal;
|
||||
|
||||
/**
|
||||
* This is the class that implements money deposit event.
|
||||
* Holds the necessary info for a money deposit event.
|
||||
* Implements the process function that finds the event related
|
||||
* domain objects and calls the related domain object's handle event functions
|
||||
* This is the class that implements money deposit event. Holds the necessary info for a money
|
||||
* deposit event. Implements the process function that finds the event related domain objects and
|
||||
* calls the related domain object's handle event functions
|
||||
*
|
||||
* Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
* <p>Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
*/
|
||||
public class MoneyDepositEvent extends DomainEvent {
|
||||
|
||||
|
||||
@ -28,12 +28,11 @@ import com.iluwatar.event.sourcing.state.AccountAggregate;
|
||||
import java.math.BigDecimal;
|
||||
|
||||
/**
|
||||
* This is the class that implements money transfer event.
|
||||
* Holds the necessary info for a money transfer event.
|
||||
* Implements the process function that finds the event related
|
||||
* domain objects and calls the related domain object's handle event functions
|
||||
* This is the class that implements money transfer event. Holds the necessary info for a money
|
||||
* transfer event. Implements the process function that finds the event related domain objects and
|
||||
* calls the related domain object's handle event functions
|
||||
*
|
||||
* Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
* <p>Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
*/
|
||||
public class MoneyTransferEvent extends DomainEvent {
|
||||
|
||||
|
||||
@ -26,11 +26,10 @@ package com.iluwatar.event.sourcing.processor;
|
||||
import com.iluwatar.event.sourcing.event.DomainEvent;
|
||||
|
||||
/**
|
||||
* This is the implementation of event processor.
|
||||
* All events are processed by this class.
|
||||
* This processor uses processorJournal to persist and recover events.
|
||||
* This is the implementation of event processor. All events are processed by this class. This
|
||||
* processor uses processorJournal to persist and recover events.
|
||||
*
|
||||
* Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
* <p>Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
*/
|
||||
public class DomainEventProcessor {
|
||||
|
||||
|
||||
@ -43,15 +43,14 @@ import java.util.ArrayList;
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* This is the implementation of event journal.
|
||||
* This implementation serialize/deserialize the events with JSON
|
||||
* and writes/reads them on a Journal.json file at the working directory.
|
||||
* This is the implementation of event journal. This implementation serialize/deserialize the events
|
||||
* with JSON and writes/reads them on a Journal.json file at the working directory.
|
||||
*
|
||||
* Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
* <p>Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
*/
|
||||
public class JsonFileJournal {
|
||||
|
||||
private final File aFile;
|
||||
private final File file;
|
||||
private final List<String> events = new ArrayList<>();
|
||||
private int index = 0;
|
||||
|
||||
@ -59,10 +58,10 @@ public class JsonFileJournal {
|
||||
* Instantiates a new Json file journal.
|
||||
*/
|
||||
public JsonFileJournal() {
|
||||
aFile = new File("Journal.json");
|
||||
if (aFile.exists()) {
|
||||
file = new File("Journal.json");
|
||||
if (file.exists()) {
|
||||
try (BufferedReader input = new BufferedReader(
|
||||
new InputStreamReader(new FileInputStream(aFile), "UTF-8"))) {
|
||||
new InputStreamReader(new FileInputStream(file), "UTF-8"))) {
|
||||
String line;
|
||||
while ((line = input.readLine()) != null) {
|
||||
events.add(line);
|
||||
@ -95,7 +94,7 @@ public class JsonFileJournal {
|
||||
}
|
||||
|
||||
try (Writer output = new BufferedWriter(
|
||||
new OutputStreamWriter(new FileOutputStream(aFile, true), "UTF-8"))) {
|
||||
new OutputStreamWriter(new FileOutputStream(file, true), "UTF-8"))) {
|
||||
String eventString = jsonElement.toString();
|
||||
output.write(eventString + "\r\n");
|
||||
} catch (IOException e) {
|
||||
@ -108,7 +107,7 @@ public class JsonFileJournal {
|
||||
* Reset.
|
||||
*/
|
||||
public void reset() {
|
||||
aFile.delete();
|
||||
file.delete();
|
||||
}
|
||||
|
||||
|
||||
|
||||
@ -28,10 +28,9 @@ import java.util.HashMap;
|
||||
import java.util.Map;
|
||||
|
||||
/**
|
||||
* This is the static accounts map holder class.
|
||||
* This class holds the state of the accounts.
|
||||
* This is the static accounts map holder class. This class holds the state of the accounts.
|
||||
*
|
||||
* Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
* <p>Created by Serdar Hamzaogullari on 06.08.2017.
|
||||
*/
|
||||
public class AccountAggregate {
|
||||
|
||||
|
||||
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Reference in New Issue
Block a user