diff --git a/.travis.yml b/.travis.yml index 613f737d7..ba226ff5c 100644 --- a/.travis.yml +++ b/.travis.yml @@ -6,6 +6,7 @@ env: global: - GH_REF: github.com/iluwatar/java-design-patterns.git - secure: LxTDuNS/rBWIvKkaEqr79ImZAe48mCdoYCF41coxNXgNoippo4GIBArknqtv+XvdkiuRZ1yGyj6pn8GU33c/yn+krddTUkVCwTbVatbalW5jhQjDbHYym/JcxaK9ZS/3JTeGcWrBgiPqHEEDhCf26vPZsXoMSeVCEORVKTp1BSg= + - secure: "eoWlW9GyTJY04P8K3pxayXwU9/hmptQg/LfirispQkV9YvmziCfSzXnatnBhNfud98sCzY8BScXnb+OWLTnjLKpId4rtEqb0aJ40Jc32cUKzgzFAUn7cNcDAbUIfyPAGVqyQqfj/11wYSADwWMMOPlW97ExUtoyiH2WenXuRHso=" before_install: - export DISPLAY=:99.0 @@ -17,6 +18,7 @@ install: after_success: - mvn clean test jacoco:report coveralls:report +- mvn clean org.jacoco:jacoco-maven-plugin:prepare-agent package sonar:sonar -Dsonar.host.url=https://sonarqube.com -Dsonar.login=$SONAR_TOKEN - bash update-ghpages.sh # use latest java version available instead of travis default diff --git a/caching/README.md b/caching/README.md index 6432ffcea..b48d060f0 100644 --- a/caching/README.md +++ b/caching/README.md @@ -27,3 +27,4 @@ Use the Caching pattern(s) when * [Write-through, write-around, write-back: Cache explained](http://www.computerweekly.com/feature/Write-through-write-around-write-back-Cache-explained) * [Read-Through, Write-Through, Write-Behind, and Refresh-Ahead Caching](https://docs.oracle.com/cd/E15357_01/coh.360/e15723/cache_rtwtwbra.htm#COHDG5177) +* [Cache-Aside](https://msdn.microsoft.com/en-us/library/dn589799.aspx) diff --git a/caching/etc/caching.png b/caching/etc/caching.png index 6b3b2d055..b6ed703ab 100644 Binary files a/caching/etc/caching.png and b/caching/etc/caching.png differ diff --git a/caching/etc/caching.ucls b/caching/etc/caching.ucls index 815a62ec9..a058277ea 100644 --- a/caching/etc/caching.ucls +++ b/caching/etc/caching.ucls @@ -1,106 +1,90 @@ - - - - - - - + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + + + + + + + + + + + + + + + + + + + - \ No newline at end of file + diff --git a/caching/src/main/java/com/iluwatar/caching/App.java b/caching/src/main/java/com/iluwatar/caching/App.java index 8e5a84085..1b1b5e1ca 100644 --- a/caching/src/main/java/com/iluwatar/caching/App.java +++ b/caching/src/main/java/com/iluwatar/caching/App.java @@ -26,22 +26,23 @@ package com.iluwatar.caching; * * The Caching pattern describes how to avoid expensive re-acquisition of resources by not releasing * the resources immediately after their use. The resources retain their identity, are kept in some - * fast-access storage, and are re-used to avoid having to acquire them again. There are three main - * caching strategies/techniques in this pattern; each with their own pros and cons. They are: + * fast-access storage, and are re-used to avoid having to acquire them again. There are four main + * caching strategies/techniques in this pattern; each with their own pros and cons. They are; * write-through which writes data to the cache and DB in a single transaction, - * write-around which writes data immediately into the DB instead of the cache, and + * write-around which writes data immediately into the DB instead of the cache, * write-behind which writes data into the cache initially whilst the data is only - * written into the DB when the cache is full. The read-through strategy is also - * included in the mentioned three strategies -- returns data from the cache to the caller if - * it exists else queries from DB and stores it into the cache for future use. These - * strategies determine when the data in the cache should be written back to the backing store (i.e. - * Database) and help keep both data sources synchronized/up-to-date. This pattern can improve - * performance and also helps to maintain consistency between data held in the cache and the data in - * the underlying data store. + * written into the DB when the cache is full, and cache-aside which pushes the + * responsibility of keeping the data synchronized in both data sources to the application itself. + * The read-through strategy is also included in the mentioned four strategies -- + * returns data from the cache to the caller if it exists else queries from DB and + * stores it into the cache for future use. These strategies determine when the data in the cache + * should be written back to the backing store (i.e. Database) and help keep both data sources + * synchronized/up-to-date. This pattern can improve performance and also helps to maintain + * consistency between data held in the cache and the data in the underlying data store. *

* In this example, the user account ({@link UserAccount}) entity is used as the underlying * application data. The cache itself is implemented as an internal (Java) data structure. It adopts - * a Least-Recently-Used (LRU) strategy for evicting data from itself when its full. The three + * a Least-Recently-Used (LRU) strategy for evicting data from itself when its full. The four * strategies are individually tested. The testing of the cache is restricted towards saving and * querying of user accounts from the underlying data store ( {@link DbManager}). The main class ( * {@link App} is not aware of the underlying mechanics of the application (i.e. save and query) and @@ -74,6 +75,7 @@ public class App { app.useReadAndWriteThroughStrategy(); app.useReadThroughAndWriteAroundStrategy(); app.useReadThroughAndWriteBehindStrategy(); + app.useCacheAsideStategy(); } /** @@ -136,4 +138,26 @@ public class App { AppManager.find("004"); System.out.println(AppManager.printCacheContent()); } + + /** + * Cache-Aside + */ + public void useCacheAsideStategy() { + System.out.println("# CachingPolicy.ASIDE"); + AppManager.initCachingPolicy(CachingPolicy.ASIDE); + System.out.println(AppManager.printCacheContent()); + + UserAccount userAccount3 = new UserAccount("003", "Adam", "He likes food."); + UserAccount userAccount4 = new UserAccount("004", "Rita", "She hates cats."); + UserAccount userAccount5 = new UserAccount("005", "Isaac", "He is allergic to mustard."); + AppManager.save(userAccount3); + AppManager.save(userAccount4); + AppManager.save(userAccount5); + + System.out.println(AppManager.printCacheContent()); + AppManager.find("003"); + System.out.println(AppManager.printCacheContent()); + AppManager.find("004"); + System.out.println(AppManager.printCacheContent()); + } } diff --git a/caching/src/main/java/com/iluwatar/caching/AppManager.java b/caching/src/main/java/com/iluwatar/caching/AppManager.java index 2967c759f..2d6a424a3 100644 --- a/caching/src/main/java/com/iluwatar/caching/AppManager.java +++ b/caching/src/main/java/com/iluwatar/caching/AppManager.java @@ -64,12 +64,7 @@ public final class AppManager { public static void initCachingPolicy(CachingPolicy policy) { cachingPolicy = policy; if (cachingPolicy == CachingPolicy.BEHIND) { - Runtime.getRuntime().addShutdownHook(new Thread(new Runnable() { - @Override - public void run() { - CacheStore.flushCache(); - } - })); + Runtime.getRuntime().addShutdownHook(new Thread(CacheStore::flushCache)); } CacheStore.clearCache(); } @@ -86,6 +81,8 @@ public final class AppManager { return CacheStore.readThrough(userId); } else if (cachingPolicy == CachingPolicy.BEHIND) { return CacheStore.readThroughWithWriteBackPolicy(userId); + } else if (cachingPolicy == CachingPolicy.ASIDE) { + return findAside(userId); } return null; } @@ -100,10 +97,37 @@ public final class AppManager { CacheStore.writeAround(userAccount); } else if (cachingPolicy == CachingPolicy.BEHIND) { CacheStore.writeBehind(userAccount); + } else if (cachingPolicy == CachingPolicy.ASIDE) { + saveAside(userAccount); } } public static String printCacheContent() { return CacheStore.print(); } + + /** + * Cache-Aside save user account helper + */ + private static void saveAside(UserAccount userAccount) { + DbManager.updateDb(userAccount); + CacheStore.invalidate(userAccount.getUserId()); + } + + /** + * Cache-Aside find user account helper + */ + private static UserAccount findAside(String userId) { + UserAccount userAccount = CacheStore.get(userId); + if (userAccount != null) { + return userAccount; + } + + userAccount = DbManager.readFromDb(userId); + if (userAccount != null) { + CacheStore.set(userId, userAccount); + } + + return userAccount; + } } diff --git a/caching/src/main/java/com/iluwatar/caching/CacheStore.java b/caching/src/main/java/com/iluwatar/caching/CacheStore.java index 5903f8219..c2b95a1bd 100644 --- a/caching/src/main/java/com/iluwatar/caching/CacheStore.java +++ b/caching/src/main/java/com/iluwatar/caching/CacheStore.java @@ -40,7 +40,7 @@ public class CacheStore { * Init cache capacity */ public static void initCapacity(int capacity) { - if (null == cache) { + if (cache == null) { cache = new LruCache(capacity); } else { cache.setCapacity(capacity); @@ -121,7 +121,7 @@ public class CacheStore { * Clears cache */ public static void clearCache() { - if (null != cache) { + if (cache != null) { cache.clear(); } } @@ -153,4 +153,25 @@ public class CacheStore { sb.append("----\n"); return sb.toString(); } + + /** + * Delegate to backing cache store + */ + public static UserAccount get(String userId) { + return cache.get(userId); + } + + /** + * Delegate to backing cache store + */ + public static void set(String userId, UserAccount userAccount) { + cache.set(userId, userAccount); + } + + /** + * Delegate to backing cache store + */ + public static void invalidate(String userId) { + cache.invalidate(userId); + } } diff --git a/caching/src/main/java/com/iluwatar/caching/CachingPolicy.java b/caching/src/main/java/com/iluwatar/caching/CachingPolicy.java index 490113baa..5ad32f699 100644 --- a/caching/src/main/java/com/iluwatar/caching/CachingPolicy.java +++ b/caching/src/main/java/com/iluwatar/caching/CachingPolicy.java @@ -24,11 +24,11 @@ package com.iluwatar.caching; /** * - * Enum class containing the three caching strategies implemented in the pattern. + * Enum class containing the four caching strategies implemented in the pattern. * */ public enum CachingPolicy { - THROUGH("through"), AROUND("around"), BEHIND("behind"); + THROUGH("through"), AROUND("around"), BEHIND("behind"), ASIDE("aside"); private String policy; diff --git a/caching/src/main/java/com/iluwatar/caching/DbManager.java b/caching/src/main/java/com/iluwatar/caching/DbManager.java index c12461d0c..455302106 100644 --- a/caching/src/main/java/com/iluwatar/caching/DbManager.java +++ b/caching/src/main/java/com/iluwatar/caching/DbManager.java @@ -82,7 +82,7 @@ public final class DbManager { } return null; } - if (null == db) { + if (db == null) { try { connect(); } catch (ParseException e) { @@ -106,7 +106,7 @@ public final class DbManager { virtualDB.put(userAccount.getUserId(), userAccount); return; } - if (null == db) { + if (db == null) { try { connect(); } catch (ParseException e) { @@ -126,7 +126,7 @@ public final class DbManager { virtualDB.put(userAccount.getUserId(), userAccount); return; } - if (null == db) { + if (db == null) { try { connect(); } catch (ParseException e) { @@ -148,7 +148,7 @@ public final class DbManager { virtualDB.put(userAccount.getUserId(), userAccount); return; } - if (null == db) { + if (db == null) { try { connect(); } catch (ParseException e) { diff --git a/caching/src/main/java/com/iluwatar/caching/LruCache.java b/caching/src/main/java/com/iluwatar/caching/LruCache.java index 5c5549afd..00e27ccf1 100644 --- a/caching/src/main/java/com/iluwatar/caching/LruCache.java +++ b/caching/src/main/java/com/iluwatar/caching/LruCache.java @@ -73,7 +73,6 @@ public class LruCache { } /** - * * Remove node from linked list. */ public void remove(Node node) { @@ -90,7 +89,6 @@ public class LruCache { } /** - * * Move node to the front of the list. */ public void setHead(Node node) { @@ -136,10 +134,11 @@ public class LruCache { * Invalidate cache for user */ public void invalidate(String userId) { - System.out.println("# " + userId + " has been updated! Removing older version from cache..."); - Node toBeRemoved = cache.get(userId); - remove(toBeRemoved); - cache.remove(userId); + Node toBeRemoved = cache.remove(userId); + if (toBeRemoved != null) { + System.out.println("# " + userId + " has been updated! Removing older version from cache..."); + remove(toBeRemoved); + } } public boolean isFull() { @@ -160,7 +159,6 @@ public class LruCache { } /** - * * Returns cache data in list form. */ public List getCacheDataInListForm() { diff --git a/caching/src/main/java/com/iluwatar/caching/UserAccount.java b/caching/src/main/java/com/iluwatar/caching/UserAccount.java index e2444ad72..657f12fa3 100644 --- a/caching/src/main/java/com/iluwatar/caching/UserAccount.java +++ b/caching/src/main/java/com/iluwatar/caching/UserAccount.java @@ -23,9 +23,7 @@ package com.iluwatar.caching; /** - * * Entity class (stored in cache and DB) used in the application. - * */ public class UserAccount { private String userId; diff --git a/caching/src/test/java/com/iluwatar/caching/CachingTest.java b/caching/src/test/java/com/iluwatar/caching/CachingTest.java index 19262a3b6..9d2299902 100644 --- a/caching/src/test/java/com/iluwatar/caching/CachingTest.java +++ b/caching/src/test/java/com/iluwatar/caching/CachingTest.java @@ -60,4 +60,9 @@ public class CachingTest { public void testReadThroughAndWriteBehindStrategy() { app.useReadThroughAndWriteBehindStrategy(); } + + @Test + public void testCacheAsideStrategy() { + app.useCacheAsideStategy(); + } } diff --git a/event-asynchronous/README.md b/event-asynchronous/README.md new file mode 100644 index 000000000..ef35d0b38 --- /dev/null +++ b/event-asynchronous/README.md @@ -0,0 +1,30 @@ +--- +layout: pattern +title: Event-based Asynchronous +folder: event-asynchronous +permalink: /patterns/event-asynchronous/ +categories: Concurrency +tags: + - difficulty-intermediate + - performance + - Java +--- + +## Intent +The Event-based Asynchronous Pattern makes available the advantages of multithreaded applications while hiding many +of the complex issues inherent in multithreaded design. Using a class that supports this pattern can allow you to:- +(1) Perform time-consuming tasks, such as downloads and database operations, "in the background," without interrupting your application. +(2) Execute multiple operations simultaneously, receiving notifications when each completes. +(3) Wait for resources to become available without stopping ("hanging") your application. +(4) Communicate with pending asynchronous operations using the familiar events-and-delegates model. + +![alt text](./etc/event-asynchronous.png "Event-based Asynchronous") + +## Applicability +Use the Event-based Asynchronous pattern(s) when + +* Time-consuming tasks are needed to run in the background without disrupting the current application. + +## Credits + +* [Event-based Asynchronous Pattern Overview](https://msdn.microsoft.com/en-us/library/wewwczdw%28v=vs.110%29.aspx?f=255&MSPPError=-2147217396) diff --git a/event-asynchronous/etc/event-asynchronous.png b/event-asynchronous/etc/event-asynchronous.png new file mode 100644 index 000000000..a46ffe1c5 Binary files /dev/null and b/event-asynchronous/etc/event-asynchronous.png differ diff --git a/event-asynchronous/etc/event-asynchronous.ucls b/event-asynchronous/etc/event-asynchronous.ucls new file mode 100644 index 000000000..df09fc28d --- /dev/null +++ b/event-asynchronous/etc/event-asynchronous.ucls @@ -0,0 +1,118 @@ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + \ No newline at end of file diff --git a/event-asynchronous/etc/event-asynchronous.urm.puml b/event-asynchronous/etc/event-asynchronous.urm.puml new file mode 100644 index 000000000..c5b183187 --- /dev/null +++ b/event-asynchronous/etc/event-asynchronous.urm.puml @@ -0,0 +1,65 @@ +@startuml +package com.iluwatar.event.asynchronous { + class Event { + - eventId : int + - eventListener : ThreadCompleteListener + - eventTime : int + - isComplete : boolean + - isSynchronous : boolean + - thread : Thread + + Event(eventId : int, eventTime : int, isSynchronous : boolean) + + addListener(listener : ThreadCompleteListener) + - completed() + + isSynchronous() : boolean + + removeListener(listener : ThreadCompleteListener) + + run() + + start() + + status() + + stop() + } + interface ThreadCompleteListener { + + completedEventHandler(int) {abstract} + } + class EventManager { + + MAX_EVENT_TIME : int {static} + + MAX_ID : int {static} + + MAX_RUNNING_EVENTS : int {static} + + MIN_ID : int {static} + - currentlyRunningSyncEvent : int + - eventPool : Map + - rand : Random + + EventManager() + + cancel(eventId : int) + + completedEventHandler(eventId : int) + + create(eventTime : int) : int + + createAsync(eventTime : int) : int + - createEvent(eventTime : int, isSynchronous : boolean) : int + - generateId() : int + + getEventPool() : Map + + numOfCurrentlyRunningSyncEvent() : int + + shutdown() + + start(eventId : int) + + status(eventId : int) + + statusOfAllEvents() + } + class App { + + PROP_FILE_NAME : String {static} + ~ interactiveMode : boolean + + App() + + main(args : String[]) {static} + + quickRun() + + run() + + runInteractiveMode() + + setUp() + } + interface IEvent { + + start() {abstract} + + status() {abstract} + + stop() {abstract} + } +} +Event --> "-eventListener" ThreadCompleteListener +EventManager --+ Map +Event ..|> IEvent +EventManager ..|> ThreadCompleteListener +@enduml \ No newline at end of file diff --git a/event-asynchronous/pom.xml b/event-asynchronous/pom.xml new file mode 100644 index 000000000..1bc4549d4 --- /dev/null +++ b/event-asynchronous/pom.xml @@ -0,0 +1,42 @@ + + + + 4.0.0 + + com.iluwatar + java-design-patterns + 1.14.0-SNAPSHOT + + event-asynchronous + + + junit + junit + test + + + diff --git a/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/App.java b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/App.java new file mode 100644 index 000000000..5a2565940 --- /dev/null +++ b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/App.java @@ -0,0 +1,206 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +import java.io.IOException; +import java.io.InputStream; +import java.util.Properties; +import java.util.Scanner; + +/** + * + * This application demonstrates the Event-based Asynchronous pattern. Essentially, users (of the pattern) may + * choose to run events in an Asynchronous or Synchronous mode. There can be multiple Asynchronous events running at + * once but only one Synchronous event can run at a time. Asynchronous events are synonymous to multi-threads. The key + * point here is that the threads run in the background and the user is free to carry on with other processes. Once an + * event is complete, the appropriate listener/callback method will be called. The listener then proceeds to carry out + * further processing depending on the needs of the user. + * + * The {@link EventManager} manages the events/threads that the user creates. Currently, the supported event operations + * are: start, stop, getStatus. For Synchronous events, the user is unable to + * start another (Synchronous) event if one is already running at the time. The running event would have to either be + * stopped or completed before a new event can be started. + * + * The Event-based Asynchronous Pattern makes available the advantages of multithreaded applications while hiding many + * of the complex issues inherent in multithreaded design. Using a class that supports this pattern can allow you to:- + * (1) Perform time-consuming tasks, such as downloads and database operations, "in the background," without + * interrupting your application. (2) Execute multiple operations simultaneously, receiving notifications when each + * completes. (3) Wait for resources to become available without stopping ("hanging") your application. (4) Communicate + * with pending asynchronous operations using the familiar events-and-delegates model. + * + * @see EventManager + * @see Event + * + */ +public class App { + + public static final String PROP_FILE_NAME = "config.properties"; + + boolean interactiveMode = false; + + /** + * Program entry point. + * + * @param args command line args + */ + public static void main(String[] args) { + App app = new App(); + + app.setUp(); + app.run(); + } + + /** + * App can run in interactive mode or not. Interactive mode == Allow user interaction with command line. + * Non-interactive is a quick sequential run through the available {@link EventManager} operations. + */ + public void setUp() { + Properties prop = new Properties(); + + InputStream inputStream = App.class.getClassLoader().getResourceAsStream(PROP_FILE_NAME); + + if (inputStream != null) { + try { + prop.load(inputStream); + } catch (IOException e) { + System.out.println(PROP_FILE_NAME + " was not found. Defaulting to non-interactive mode."); + } + String property = prop.getProperty("INTERACTIVE_MODE"); + if (property.equalsIgnoreCase("YES")) { + interactiveMode = true; + } + } + } + + /** + * Run program in either interactive mode or not. + */ + public void run() { + if (interactiveMode) { + runInteractiveMode(); + } else { + quickRun(); + } + } + + /** + * Run program in non-interactive mode. + */ + public void quickRun() { + EventManager eventManager = new EventManager(); + + try { + // Create an Asynchronous event. + int aEventId = eventManager.createAsync(60); + System.out.println("Async Event [" + aEventId + "] has been created."); + eventManager.start(aEventId); + System.out.println("Async Event [" + aEventId + "] has been started."); + + // Create a Synchronous event. + int sEventId = eventManager.create(60); + System.out.println("Sync Event [" + sEventId + "] has been created."); + eventManager.start(sEventId); + System.out.println("Sync Event [" + sEventId + "] has been started."); + + eventManager.status(aEventId); + eventManager.status(sEventId); + + eventManager.cancel(aEventId); + System.out.println("Async Event [" + aEventId + "] has been stopped."); + eventManager.cancel(sEventId); + System.out.println("Sync Event [" + sEventId + "] has been stopped."); + + } catch (MaxNumOfEventsAllowedException | LongRunningEventException | EventDoesNotExistException + | InvalidOperationException e) { + System.out.println(e.getMessage()); + } + } + + /** + * Run program in interactive mode. + */ + public void runInteractiveMode() { + EventManager eventManager = new EventManager(); + + Scanner s = new Scanner(System.in); + int option = -1; + while (option != 4) { + System.out.println("Hello. Would you like to boil some eggs?"); + System.out.println("(1) BOIL AN EGG \n(2) STOP BOILING THIS EGG \n(3) HOW ARE MY EGGS? \n(4) EXIT"); + System.out.print("Choose [1,2,3,4]: "); + option = s.nextInt(); + + if (option == 1) { + s.nextLine(); + System.out.print("Boil multiple eggs at once (A) or boil them one-by-one (S)?: "); + String eventType = s.nextLine(); + System.out.print("How long should this egg be boiled for (in seconds)?: "); + int eventTime = s.nextInt(); + if (eventType.equalsIgnoreCase("A")) { + try { + int eventId = eventManager.createAsync(eventTime); + eventManager.start(eventId); + System.out.println("Egg [" + eventId + "] is being boiled."); + } catch (MaxNumOfEventsAllowedException | LongRunningEventException | EventDoesNotExistException e) { + System.out.println(e.getMessage()); + } + } else if (eventType.equalsIgnoreCase("S")) { + try { + int eventId = eventManager.create(eventTime); + eventManager.start(eventId); + System.out.println("Egg [" + eventId + "] is being boiled."); + } catch (MaxNumOfEventsAllowedException | InvalidOperationException | LongRunningEventException + | EventDoesNotExistException e) { + System.out.println(e.getMessage()); + } + } else { + System.out.println("Unknown event type."); + } + } else if (option == 2) { + System.out.print("Which egg?: "); + int eventId = s.nextInt(); + try { + eventManager.cancel(eventId); + System.out.println("Egg [" + eventId + "] is removed from boiler."); + } catch (EventDoesNotExistException e) { + System.out.println(e.getMessage()); + } + } else if (option == 3) { + s.nextLine(); + System.out.print("Just one egg (O) OR all of them (A) ?: "); + String eggChoice = s.nextLine(); + + if (eggChoice.equalsIgnoreCase("O")) { + System.out.print("Which egg?: "); + int eventId = s.nextInt(); + try { + eventManager.status(eventId); + } catch (EventDoesNotExistException e) { + System.out.println(e.getMessage()); + } + } else if (eggChoice.equalsIgnoreCase("A")) { + eventManager.statusOfAllEvents(); + } + } else if (option == 4) { + eventManager.shutdown(); + } + } + + s.close(); + } + +} diff --git a/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/Event.java b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/Event.java new file mode 100644 index 000000000..5e557fff2 --- /dev/null +++ b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/Event.java @@ -0,0 +1,101 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +/** + * + * Each Event runs as a separate/individual thread. + * + */ +public class Event implements IEvent, Runnable { + + private int eventId; + private int eventTime; + private boolean isSynchronous; + private Thread thread; + private boolean isComplete = false; + private ThreadCompleteListener eventListener; + + /** + * + * @param eventId event ID + * @param eventTime event time + * @param isSynchronous is of synchronous type + */ + public Event(final int eventId, final int eventTime, final boolean isSynchronous) { + this.eventId = eventId; + this.eventTime = eventTime; + this.isSynchronous = isSynchronous; + } + + public boolean isSynchronous() { + return isSynchronous; + } + + @Override + public void start() { + thread = new Thread(this); + thread.start(); + } + + @Override + public void stop() { + if (null == thread) { + return; + } + thread.interrupt(); + } + + @Override + public void status() { + if (!isComplete) { + System.out.println("[" + eventId + "] is not done."); + } else { + System.out.println("[" + eventId + "] is done."); + } + } + + @Override + public void run() { + long currentTime = System.currentTimeMillis(); + long endTime = currentTime + (eventTime * 1000); + while (System.currentTimeMillis() < endTime) { + try { + Thread.sleep(1000); // Sleep for 1 second. + } catch (InterruptedException e) { + return; + } + } + isComplete = true; + completed(); + } + + public final void addListener(final ThreadCompleteListener listener) { + this.eventListener = listener; + } + + public final void removeListener(final ThreadCompleteListener listener) { + this.eventListener = null; + } + + private final void completed() { + if (eventListener != null) { + eventListener.completedEventHandler(eventId); + } + } + +} diff --git a/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/EventDoesNotExistException.java b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/EventDoesNotExistException.java new file mode 100644 index 000000000..77c1d479b --- /dev/null +++ b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/EventDoesNotExistException.java @@ -0,0 +1,26 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +public class EventDoesNotExistException extends Exception { + + private static final long serialVersionUID = -3398463738273811509L; + + public EventDoesNotExistException(String message) { + super(message); + } +} diff --git a/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/EventManager.java b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/EventManager.java new file mode 100644 index 000000000..dae995e38 --- /dev/null +++ b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/EventManager.java @@ -0,0 +1,218 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +import java.util.Iterator; +import java.util.Map; +import java.util.Random; +import java.util.concurrent.ConcurrentHashMap; + +/** + * + * EventManager handles and maintains a pool of event threads. {@link Event} threads are created upon user request. Thre + * are two types of events; Asynchronous and Synchronous. There can be multiple Asynchronous events running at once but + * only one Synchronous event running at a time. Currently supported event operations are: start, stop, and getStatus. + * Once an event is complete, it then notifies EventManager through a listener. The EventManager then takes the event + * out of the pool. + * + */ +public class EventManager implements ThreadCompleteListener { + + public static final int MAX_RUNNING_EVENTS = 1000; // Just don't wanna have too many running events. :) + public static final int MIN_ID = 1; + public static final int MAX_ID = MAX_RUNNING_EVENTS; + public static final int MAX_EVENT_TIME = 1800; // in seconds / 30 minutes. + private int currentlyRunningSyncEvent = -1; + private Random rand; + private Map eventPool; + + /** + * EventManager constructor. + * + */ + public EventManager() { + rand = new Random(1); + eventPool = new ConcurrentHashMap(MAX_RUNNING_EVENTS); + + } + + /** + * Create a Synchronous event. + * + * @param eventTime Time an event should run for. + * @return eventId + * @throws MaxNumOfEventsAllowedException When too many events are running at a time. + * @throws InvalidOperationException No new synchronous events can be created when one is already running. + * @throws LongRunningEventException Long running events are not allowed in the app. + */ + public int create(int eventTime) + throws MaxNumOfEventsAllowedException, InvalidOperationException, LongRunningEventException { + if (currentlyRunningSyncEvent != -1) { + throw new InvalidOperationException( + "Event [" + currentlyRunningSyncEvent + "] is still running. Please wait until it finishes and try again."); + } + + int eventId = createEvent(eventTime, true); + currentlyRunningSyncEvent = eventId; + + return eventId; + } + + /** + * Create an Asynchronous event. + * + * @param eventTime Time an event should run for. + * @return eventId + * @throws MaxNumOfEventsAllowedException When too many events are running at a time. + * @throws LongRunningEventException Long running events are not allowed in the app. + */ + public int createAsync(int eventTime) throws MaxNumOfEventsAllowedException, LongRunningEventException { + return createEvent(eventTime, false); + } + + private int createEvent(int eventTime, boolean isSynchronous) + throws MaxNumOfEventsAllowedException, LongRunningEventException { + if (eventPool.size() == MAX_RUNNING_EVENTS) { + throw new MaxNumOfEventsAllowedException("Too many events are running at the moment. Please try again later."); + } + + if (eventTime >= MAX_EVENT_TIME) { + throw new LongRunningEventException( + "Maximum event time allowed is " + MAX_EVENT_TIME + " seconds. Please try again."); + } + + int newEventId = generateId(); + + Event newEvent = new Event(newEventId, eventTime, isSynchronous); + newEvent.addListener(this); + eventPool.put(newEventId, newEvent); + + return newEventId; + } + + /** + * Starts event. + * + * @param eventId The event that needs to be started. + * @throws EventDoesNotExistException If event does not exist in our eventPool. + */ + public void start(int eventId) throws EventDoesNotExistException { + if (!eventPool.containsKey(eventId)) { + throw new EventDoesNotExistException(eventId + " does not exist."); + } + + eventPool.get(eventId).start(); + } + + /** + * Stops event. + * + * @param eventId The event that needs to be stopped. + * @throws EventDoesNotExistException If event does not exist in our eventPool. + */ + public void cancel(int eventId) throws EventDoesNotExistException { + if (!eventPool.containsKey(eventId)) { + throw new EventDoesNotExistException(eventId + " does not exist."); + } + + if (eventId == currentlyRunningSyncEvent) { + currentlyRunningSyncEvent = -1; + } + + eventPool.get(eventId).stop(); + eventPool.remove(eventId); + } + + /** + * Get status of a running event. + * + * @param eventId The event to inquire status of. + * @throws EventDoesNotExistException If event does not exist in our eventPool. + */ + public void status(int eventId) throws EventDoesNotExistException { + if (!eventPool.containsKey(eventId)) { + throw new EventDoesNotExistException(eventId + " does not exist."); + } + + eventPool.get(eventId).status(); + } + + /** + * Gets status of all running events. + */ + @SuppressWarnings("rawtypes") + public void statusOfAllEvents() { + Iterator it = eventPool.entrySet().iterator(); + while (it.hasNext()) { + Map.Entry pair = (Map.Entry) it.next(); + ((Event) pair.getValue()).status(); + } + } + + /** + * Stop all running events. + */ + @SuppressWarnings("rawtypes") + public void shutdown() { + Iterator it = eventPool.entrySet().iterator(); + while (it.hasNext()) { + Map.Entry pair = (Map.Entry) it.next(); + ((Event) pair.getValue()).stop(); + } + } + + /** + * Returns a pseudo-random number between min and max, inclusive. The difference between min and max can be at most + * Integer.MAX_VALUE - 1. + */ + private int generateId() { + // nextInt is normally exclusive of the top value, + // so add 1 to make it inclusive + int randomNum = rand.nextInt((MAX_ID - MIN_ID) + 1) + MIN_ID; + while (eventPool.containsKey(randomNum)) { + randomNum = rand.nextInt((MAX_ID - MIN_ID) + 1) + MIN_ID; + } + + return randomNum; + } + + /** + * Callback from an {@link Event} (once it is complete). The Event is then removed from the pool. + */ + @Override + public void completedEventHandler(int eventId) { + eventPool.get(eventId).status(); + if (eventPool.get(eventId).isSynchronous()) { + currentlyRunningSyncEvent = -1; + } + eventPool.remove(eventId); + } + + /** + * Getter method for event pool. + */ + public Map getEventPool() { + return eventPool; + } + + /** + * Get number of currently running Synchronous events. + */ + public int numOfCurrentlyRunningSyncEvent() { + return currentlyRunningSyncEvent; + } +} diff --git a/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/IEvent.java b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/IEvent.java new file mode 100644 index 000000000..bcd78b6c0 --- /dev/null +++ b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/IEvent.java @@ -0,0 +1,27 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +public interface IEvent { + + void start(); + + void stop(); + + void status(); + +} diff --git a/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/InvalidOperationException.java b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/InvalidOperationException.java new file mode 100644 index 000000000..4fd5b0eed --- /dev/null +++ b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/InvalidOperationException.java @@ -0,0 +1,27 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +public class InvalidOperationException extends Exception { + + private static final long serialVersionUID = -6191545255213410803L; + + public InvalidOperationException(String message) { + super(message); + } + +} diff --git a/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/LongRunningEventException.java b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/LongRunningEventException.java new file mode 100644 index 000000000..6817b1dd8 --- /dev/null +++ b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/LongRunningEventException.java @@ -0,0 +1,26 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +public class LongRunningEventException extends Exception { + + private static final long serialVersionUID = -483423544320148809L; + + public LongRunningEventException(String message) { + super(message); + } +} diff --git a/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/MaxNumOfEventsAllowedException.java b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/MaxNumOfEventsAllowedException.java new file mode 100644 index 000000000..9f8f2891c --- /dev/null +++ b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/MaxNumOfEventsAllowedException.java @@ -0,0 +1,26 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +public class MaxNumOfEventsAllowedException extends Exception { + + private static final long serialVersionUID = -8430876973516292695L; + + public MaxNumOfEventsAllowedException(String message) { + super(message); + } +} diff --git a/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/ThreadCompleteListener.java b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/ThreadCompleteListener.java new file mode 100644 index 000000000..fd62a3e80 --- /dev/null +++ b/event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/ThreadCompleteListener.java @@ -0,0 +1,21 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +public interface ThreadCompleteListener { + void completedEventHandler(final int eventId); +} diff --git a/event-asynchronous/src/main/resources/config.properties b/event-asynchronous/src/main/resources/config.properties new file mode 100644 index 000000000..d8bfa1f7e --- /dev/null +++ b/event-asynchronous/src/main/resources/config.properties @@ -0,0 +1,24 @@ +# +# The MIT License +# Copyright (c) 2014 Ilkka Seppälä +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in +# all copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +# THE SOFTWARE. +# + +INTERACTIVE_MODE=NO \ No newline at end of file diff --git a/event-asynchronous/src/test/java/com/iluwatar/event/asynchronous/AppTest.java b/event-asynchronous/src/test/java/com/iluwatar/event/asynchronous/AppTest.java new file mode 100644 index 000000000..8736fcf77 --- /dev/null +++ b/event-asynchronous/src/test/java/com/iluwatar/event/asynchronous/AppTest.java @@ -0,0 +1,32 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +import java.io.IOException; + +import org.junit.Test; + +/** + * Tests that EventAsynchronous example runs without errors. + */ +public class AppTest { + @Test + public void test() throws IOException { + String[] args = {}; + App.main(args); + } +} diff --git a/event-asynchronous/src/test/java/com/iluwatar/event/asynchronous/EventAsynchronousTest.java b/event-asynchronous/src/test/java/com/iluwatar/event/asynchronous/EventAsynchronousTest.java new file mode 100644 index 000000000..213439203 --- /dev/null +++ b/event-asynchronous/src/test/java/com/iluwatar/event/asynchronous/EventAsynchronousTest.java @@ -0,0 +1,135 @@ +/** + * The MIT License Copyright (c) 2014 Ilkka Seppälä + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated + * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +package com.iluwatar.event.asynchronous; + +import static org.junit.Assert.assertTrue; + +import org.junit.Before; +import org.junit.Test; + +/** + * + * Application test + * + */ +public class EventAsynchronousTest { + App app; + + @Before + public void setUp() { + app = new App(); + } + + @Test + public void testAsynchronousEvent() { + EventManager eventManager = new EventManager(); + try { + int aEventId = eventManager.createAsync(60); + eventManager.start(aEventId); + assertTrue(eventManager.getEventPool().size() == 1); + assertTrue(eventManager.getEventPool().size() < EventManager.MAX_RUNNING_EVENTS); + assertTrue(eventManager.numOfCurrentlyRunningSyncEvent() == -1); + eventManager.cancel(aEventId); + assertTrue(eventManager.getEventPool().size() == 0); + } catch (MaxNumOfEventsAllowedException | LongRunningEventException | EventDoesNotExistException e) { + System.out.println(e.getMessage()); + } + } + + @Test + public void testSynchronousEvent() { + EventManager eventManager = new EventManager(); + try { + int sEventId = eventManager.create(60); + eventManager.start(sEventId); + assertTrue(eventManager.getEventPool().size() == 1); + assertTrue(eventManager.getEventPool().size() < EventManager.MAX_RUNNING_EVENTS); + assertTrue(eventManager.numOfCurrentlyRunningSyncEvent() != -1); + eventManager.cancel(sEventId); + assertTrue(eventManager.getEventPool().size() == 0); + } catch (MaxNumOfEventsAllowedException | LongRunningEventException | EventDoesNotExistException + | InvalidOperationException e) { + System.out.println(e.getMessage()); + } + } + + @Test(expected = InvalidOperationException.class) + public void testUnsuccessfulSynchronousEvent() throws InvalidOperationException { + EventManager eventManager = new EventManager(); + try { + int sEventId = eventManager.create(60); + eventManager.start(sEventId); + sEventId = eventManager.create(60); + eventManager.start(sEventId); + } catch (MaxNumOfEventsAllowedException | LongRunningEventException | EventDoesNotExistException e) { + System.out.println(e.getMessage()); + } + } + + @Test + public void testFullSynchronousEvent() { + EventManager eventManager = new EventManager(); + try { + int eventTime = 1; + + int sEventId = eventManager.create(eventTime); + assertTrue(eventManager.getEventPool().size() == 1); + eventManager.start(sEventId); + + long currentTime = System.currentTimeMillis(); + long endTime = currentTime + (eventTime + 2 * 1000); // +2 to give a bit of buffer time for event to + // complete + // properly. + while (System.currentTimeMillis() < endTime) { + } + + assertTrue(eventManager.getEventPool().size() == 0); + + } catch (MaxNumOfEventsAllowedException | LongRunningEventException | EventDoesNotExistException + | InvalidOperationException e) { + System.out.println(e.getMessage()); + } + } + + @Test + public void testFullAsynchronousEvent() { + EventManager eventManager = new EventManager(); + try { + int eventTime = 1; + + int aEventId1 = eventManager.createAsync(eventTime); + int aEventId2 = eventManager.createAsync(eventTime); + int aEventId3 = eventManager.createAsync(eventTime); + assertTrue(eventManager.getEventPool().size() == 3); + + eventManager.start(aEventId1); + eventManager.start(aEventId2); + eventManager.start(aEventId3); + + long currentTime = System.currentTimeMillis(); + long endTime = currentTime + (eventTime + 2 * 1000); // +2 to give a bit of buffer time for event to complete + // properly. + while (System.currentTimeMillis() < endTime) { + } + + assertTrue(eventManager.getEventPool().size() == 0); + + } catch (MaxNumOfEventsAllowedException | LongRunningEventException | EventDoesNotExistException e) { + System.out.println(e.getMessage()); + } + } +} diff --git a/pom.xml b/pom.xml index 7aec509d4..598386753 100644 --- a/pom.xml +++ b/pom.xml @@ -132,8 +132,13 @@ aggregator-microservices promise page-object +<<<<<<< HEAD object-mother +======= + event-asynchronous + +>>>>>>> refs/remotes/iluwatar/master diff --git a/service-locator/README.md b/service-locator/README.md index 31d82b13f..479c9ed0f 100644 --- a/service-locator/README.md +++ b/service-locator/README.md @@ -33,6 +33,12 @@ improves the performance of application to great extent. * lookups of services are done quite frequently * large number of services are being used +## Consequences + +* Violates Interface Segregation Principle (ISP) by providing pattern consumers with an access +to a number of services that they don't potentially need. +* Creates hidden dependencies that can break the clients at runtime. + ## Credits * [J2EE Design Patterns](http://www.amazon.com/J2EE-Design-Patterns-William-Crawford/dp/0596004273/ref=sr_1_2) diff --git a/singleton/README.md b/singleton/README.md index e1bb42a45..4032ffaed 100644 --- a/singleton/README.md +++ b/singleton/README.md @@ -36,6 +36,13 @@ Use the Singleton pattern when * [java.lang.System#getSecurityManager()](http://docs.oracle.com/javase/8/docs/api/java/lang/System.html#getSecurityManager--) +## Consequences + +* Violates Single Responsibility Principle (SRP) by controlling their own creation and lifecycle. +* Encourages using a global shared instance which prevents an object and resources used by this object from being deallocated. +* Creates tightly coupled code that is difficult to test. +* Makes it almost impossible to subclass a Singleton. + ## Credits * [Design Patterns: Elements of Reusable Object-Oriented Software](http://www.amazon.com/Design-Patterns-Elements-Reusable-Object-Oriented/dp/0201633612)