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Resolves checkstyle errors for naked-objects null-object object-mother object-pool observer queue-load-leveling (#1082)

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* Reduces checkstyle errors in naked-objects

* Reduces checkstyle errors in null-object

* Reduces checkstyle errors in object-mother

* Reduces checkstyle errors in object-pool

* Reduces checkstyle errors in observer

* Reduces checkstyle errors in queue-load-leveling
This commit is contained in:
Anurag Agarwal 2019-11-13 00:56:15 +05:30 committed by Ilkka Seppälä
parent 1e76d91929
commit 6ef840f3cf
41 changed files with 242 additions and 288 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
naked-objects/dom/src/main/java/domainapp/dom/app/homepage/HomePageService.java
View File

@ -31,7 +31,8 @@ import org.apache.isis.applib.annotation.NatureOfService;
import org.apache.isis.applib.annotation.SemanticsOf;
/**
* HomePage Domain Service
* HomePage Domain Service.
*
* @see HomePageViewModel linked view to HomePage
*/
@DomainService(nature = NatureOfService.VIEW_CONTRIBUTIONS_ONLY)

10
naked-objects/dom/src/main/java/domainapp/dom/app/homepage/HomePageViewModel.java
View File

@ -23,16 +23,14 @@
package domainapp.dom.app.homepage;
import java.util.List;
import org.apache.isis.applib.annotation.ViewModel;
import domainapp.dom.modules.simple.SimpleObject;
import domainapp.dom.modules.simple.SimpleObjects;
import java.util.List;
import org.apache.isis.applib.annotation.ViewModel;
/**
* Model linked to the HomePage
* The underlying layout is specified by json
* Model linked to the HomePage The underlying layout is specified by json.
*
* @see HomePageService - Service Linked to the HomePage
*/
@ViewModel

48
naked-objects/dom/src/main/java/domainapp/dom/app/homepage/HomePageViewModel.layout.json
View File

@ -15,29 +15,29 @@
* limitations under the License.
*/
{
"columns": [
{
"span": 0,
"memberGroups": {}
},
{
"span": 0,
"memberGroups": {}
},
{
"span": 0,
"memberGroups": {}
},
{
"span": 12,
"collections": {
"objects": {
"collectionLayout": {
"render": "EAGERLY"
}
}
}
"columns": [
{
"span": 0,
"memberGroups": {}
},
{
"span": 0,
"memberGroups": {}
},
{
"span": 0,
"memberGroups": {}
},
{
"span": 12,
"collections": {
"objects": {
"collectionLayout": {
"render": "EAGERLY"
}
}
],
"actions": {}
}
}
],
"actions": {}
}

7
naked-objects/dom/src/main/java/domainapp/dom/modules/simple/SimpleObject.java
View File

@ -26,7 +26,6 @@ package domainapp.dom.modules.simple;
import javax.jdo.JDOHelper;
import javax.jdo.annotations.IdentityType;
import javax.jdo.annotations.VersionStrategy;
import org.apache.isis.applib.DomainObjectContainer;
import org.apache.isis.applib.Identifier;
import org.apache.isis.applib.annotation.Action;
@ -43,7 +42,7 @@ import org.apache.isis.applib.services.i18n.TranslatableString;
import org.apache.isis.applib.util.ObjectContracts;
/**
* Definition of a Simple Object
* Definition of a Simple Object.
*/
@javax.jdo.annotations.PersistenceCapable(identityType = IdentityType.DATASTORE, schema = "simple",
table = "SimpleObject")
@ -87,11 +86,11 @@ public class SimpleObject implements Comparable<SimpleObject> {
// region > updateName (action)
/**
* Event used to update the Name in the Domain
* Event used to update the Name in the Domain.
*/
public static class UpdateNameDomainEvent extends ActionDomainEvent<SimpleObject> {
public UpdateNameDomainEvent(final SimpleObject source, final Identifier identifier,
final Object... arguments) {
final Object... arguments) {
super(source, identifier, arguments);
}
}

70
naked-objects/dom/src/main/java/domainapp/dom/modules/simple/SimpleObject.layout.json
View File

@ -15,42 +15,42 @@
* limitations under the License.
*/
{
"columns": [
{
"span": 6,
"memberGroups": {
"General": {
"members": {
"name": {
"actions": {
"updateName": {
"actionLayout": {
"position": "BOTTOM"
}
}
}
},
"versionSequence": {
"propertyLayout": {
"name": "version"
}
}
}
"columns": [
{
"span": 6,
"memberGroups": {
"General": {
"members": {
"name": {
"actions": {
"updateName": {
"actionLayout": {
"position": "BOTTOM"
}
}
}
},
"versionSequence": {
"propertyLayout": {
"name": "version"
}
}
},
{
"span": 0,
"memberGroups": {}
},
{
"span": 0,
"memberGroups": {}
},
{
"span": 6,
"collections": {}
}
}
],
"actions": {}
}
},
{
"span": 0,
"memberGroups": {}
},
{
"span": 0,
"memberGroups": {}
},
{
"span": 6,
"collections": {}
}
],
"actions": {}
}

9
naked-objects/dom/src/main/java/domainapp/dom/modules/simple/SimpleObjects.java
View File

@ -24,7 +24,6 @@
package domainapp.dom.modules.simple;
import java.util.List;
import org.apache.isis.applib.DomainObjectContainer;
import org.apache.isis.applib.Identifier;
import org.apache.isis.applib.annotation.Action;
@ -40,7 +39,7 @@ import org.apache.isis.applib.services.eventbus.ActionDomainEvent;
import org.apache.isis.applib.services.i18n.TranslatableString;
/**
* Domain Service for Simple Objects
* Domain Service for Simple Objects.
*/
@DomainService(repositoryFor = SimpleObject.class)
@DomainServiceLayout(menuOrder = "10")
@ -82,18 +81,18 @@ public class SimpleObjects {
// endregion
/**
* Create Domain Event on SimpleObjects
* Create Domain Event on SimpleObjects.
*/
// region > create (action)
public static class CreateDomainEvent extends ActionDomainEvent<SimpleObjects> {
public CreateDomainEvent(final SimpleObjects source, final Identifier identifier,
final Object... arguments) {
final Object... arguments) {
super(source, identifier, arguments);
}
}
/**
* Create simple object
* Create simple object.
*/
@Action(domainEvent = CreateDomainEvent.class)
@MemberOrder(sequence = "3")

3
naked-objects/fixture/src/main/java/domainapp/fixture/DomainAppFixturesProvider.java
View File

@ -23,14 +23,13 @@
package domainapp.fixture;
import domainapp.fixture.scenarios.RecreateSimpleObjects;
import org.apache.isis.applib.annotation.DomainService;
import org.apache.isis.applib.annotation.NatureOfService;
import org.apache.isis.applib.fixturescripts.FixtureScripts;
import org.apache.isis.applib.services.fixturespec.FixtureScriptsSpecification;
import org.apache.isis.applib.services.fixturespec.FixtureScriptsSpecificationProvider;
import domainapp.fixture.scenarios.RecreateSimpleObjects;
/**
* Specifies where to find fixtures, and other settings.
*/

7
naked-objects/fixture/src/main/java/domainapp/fixture/modules/simple/SimpleObjectCreate.java
View File

@ -23,13 +23,12 @@
package domainapp.fixture.modules.simple;
import org.apache.isis.applib.fixturescripts.FixtureScript;
import domainapp.dom.modules.simple.SimpleObject;
import domainapp.dom.modules.simple.SimpleObjects;
import org.apache.isis.applib.fixturescripts.FixtureScript;
/**
* Fixture to create a simple object
* Fixture to create a simple object.
*/
public class SimpleObjectCreate extends FixtureScript {
@ -46,7 +45,7 @@ public class SimpleObjectCreate extends FixtureScript {
private String name;
/**
* Name of the object (required)
* Name of the object (required).
*/
public String getName() {
return name;

2
naked-objects/fixture/src/main/java/domainapp/fixture/modules/simple/SimpleObjectsTearDown.java
View File

@ -27,7 +27,7 @@ import org.apache.isis.applib.fixturescripts.FixtureScript;
import org.apache.isis.applib.services.jdosupport.IsisJdoSupport;
/**
* TearDown/Cleanup for SimpleObjects
* TearDown/Cleanup for SimpleObjects.
*/
public class SimpleObjectsTearDown extends FixtureScript {

7
naked-objects/fixture/src/main/java/domainapp/fixture/scenarios/RecreateSimpleObjects.java
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@ -27,19 +27,18 @@ import com.google.common.collect.Lists;
import domainapp.dom.modules.simple.SimpleObject;
import domainapp.fixture.modules.simple.SimpleObjectCreate;
import domainapp.fixture.modules.simple.SimpleObjectsTearDown;
import org.apache.isis.applib.fixturescripts.FixtureScript;
import java.util.Collections;
import java.util.List;
import org.apache.isis.applib.fixturescripts.FixtureScript;
/**
* Create a bunch of simple Objects
* Create a bunch of simple Objects.
*/
public class RecreateSimpleObjects extends FixtureScript {
public final List<String> names = Collections.unmodifiableList(List.of("Foo", "Bar", "Baz",
"Frodo", "Froyo", "Fizz", "Bip", "Bop", "Bang", "Boo"));
"Frodo", "Froyo", "Fizz", "Bip", "Bop", "Bang", "Boo"));
// region > number (optional input)
private Integer number;

42
naked-objects/webapp/src/main/java/domainapp/webapp/SimpleApplication.java
View File

@ -23,13 +23,6 @@
package domainapp.webapp;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import com.google.common.base.Joiner;
import com.google.common.io.Resources;
import com.google.inject.AbstractModule;
@ -37,30 +30,31 @@ import com.google.inject.Module;
import com.google.inject.name.Names;
import com.google.inject.util.Modules;
import com.google.inject.util.Providers;
import de.agilecoders.wicket.core.Bootstrap;
import de.agilecoders.wicket.core.settings.IBootstrapSettings;
import de.agilecoders.wicket.themes.markup.html.bootswatch.BootswatchTheme;
import de.agilecoders.wicket.themes.markup.html.bootswatch.BootswatchThemeProvider;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import org.apache.isis.viewer.wicket.viewer.IsisWicketApplication;
import org.apache.isis.viewer.wicket.viewer.integration.wicket.AuthenticatedWebSessionForIsis;
import org.apache.wicket.Session;
import org.apache.wicket.request.IRequestParameters;
import org.apache.wicket.request.Request;
import org.apache.wicket.request.Response;
import org.apache.wicket.request.http.WebRequest;
import org.apache.isis.viewer.wicket.viewer.IsisWicketApplication;
import org.apache.isis.viewer.wicket.viewer.integration.wicket.AuthenticatedWebSessionForIsis;
import de.agilecoders.wicket.core.Bootstrap;
import de.agilecoders.wicket.core.settings.IBootstrapSettings;
import de.agilecoders.wicket.themes.markup.html.bootswatch.BootswatchTheme;
import de.agilecoders.wicket.themes.markup.html.bootswatch.BootswatchThemeProvider;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* As specified in <tt>web.xml</tt>.
*
* <p>
* See:
*
*
* <p>See:
*
* <pre>
* &lt;filter&gt;
* &lt;filter-name&gt;wicket&lt;/filter-name&gt;
@ -71,7 +65,6 @@ import org.slf4j.LoggerFactory;
* &lt;/init-param&gt;
* &lt;/filter&gt;
* </pre>
*
*/
public class SimpleApplication extends IsisWicketApplication {
@ -80,11 +73,10 @@ public class SimpleApplication extends IsisWicketApplication {
/**
* uncomment for a (slightly hacky) way of allowing logins using query args, eg:
*
*
* <tt>{@code ?user=sven&pass=pass}</tt>
*
* <p>
* for demos only, obvious.
*
* <p>for demos only, obvious.
*/
private static final boolean DEMO_MODE_USING_CREDENTIALS_AS_QUERYARGS = false;

12
null-object/src/main/java/com/iluwatar/nullobject/App.java
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@ -24,18 +24,16 @@
package com.iluwatar.nullobject;
/**
*
* Null Object pattern replaces null values with neutral objects. Many times this simplifies
* algorithms since no extra null checks are needed.
* <p>
* In this example we build a binary tree where the nodes are either normal or Null Objects. No null
* values are used in the tree making the traversal easy.
*
* <p>In this example we build a binary tree where the nodes are either normal or Null Objects. No
* null values are used in the tree making the traversal easy.
*/
public class App {
/**
* Program entry point
*
* Program entry point.
*
* @param args command line args
*/
public static void main(String[] args) {
@ -44,7 +42,7 @@ public class App {
new NodeImpl("1", new NodeImpl("11", new NodeImpl("111", NullNode.getInstance(),
NullNode.getInstance()), NullNode.getInstance()), new NodeImpl("12",
NullNode.getInstance(), new NodeImpl("122", NullNode.getInstance(),
NullNode.getInstance())));
NullNode.getInstance())));
root.walk();
}

2
null-object/src/main/java/com/iluwatar/nullobject/Node.java
View File

@ -24,9 +24,7 @@
package com.iluwatar.nullobject;
/**
*
* Interface for binary tree node.
*
*/
public interface Node {

4
null-object/src/main/java/com/iluwatar/nullobject/NodeImpl.java
View File

@ -27,9 +27,7 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* Implementation for binary tree's normal nodes.
*
*/
public class NodeImpl implements Node {
@ -40,7 +38,7 @@ public class NodeImpl implements Node {
private final Node right;
/**
* Constructor
* Constructor.
*/
public NodeImpl(String name, Node left, Node right) {
this.name = name;

7
null-object/src/main/java/com/iluwatar/nullobject/NullNode.java
View File

@ -24,17 +24,16 @@
package com.iluwatar.nullobject;
/**
*
* Null Object implementation for binary tree node.
* <p>
* Implemented as Singleton, since all the NullNodes are the same.
*
* <p>Implemented as Singleton, since all the NullNodes are the same.
*/
public final class NullNode implements Node {
private static NullNode instance = new NullNode();
private NullNode() {}
private NullNode() {
}
public static NullNode getInstance() {
return instance;

3
object-mother/src/main/java/com/iluwatar/objectmother/King.java
View File

@ -24,7 +24,7 @@
package com.iluwatar.objectmother;
/**
* Defines all attributes and behaviour related to the King
* Defines all attributes and behaviour related to the King.
*/
public class King implements Royalty {
boolean isDrunk = false;
@ -56,6 +56,7 @@ public class King implements Royalty {
/**
* Method to flirt to a queen.
*
* @param queen Queen which should be flirted.
*/
public void flirt(Queen queen) {

3
object-mother/src/main/java/com/iluwatar/objectmother/Queen.java
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@ -24,7 +24,7 @@
package com.iluwatar.objectmother;
/**
* Defines all attributes and behaviour related to the Queen
* Defines all attributes and behaviour related to the Queen.
*/
public class Queen implements Royalty {
private boolean isDrunk = false;
@ -61,6 +61,7 @@ public class Queen implements Royalty {
/**
* Method which is called when the king is flirting to a queen.
*
* @param king King who initialized the flirt.
* @return A value which describes if the flirt was successful or not.
*/

2
object-mother/src/main/java/com/iluwatar/objectmother/Royalty.java
View File

@ -24,7 +24,7 @@
package com.iluwatar.objectmother;
/**
* Interface contracting Royalty Behaviour
* Interface contracting Royalty Behaviour.
*/
public interface Royalty {
void makeDrunk();

8
object-mother/src/main/java/com/iluwatar/objectmother/RoyaltyObjectMother.java
View File

@ -24,12 +24,13 @@
package com.iluwatar.objectmother;
/**
* Object Mother Pattern generating Royalty Types
* Object Mother Pattern generating Royalty Types.
*/
public final class RoyaltyObjectMother {
/**
* Method to create a sober and unhappy king. The standard parameters are set.
*
* @return An instance of {@link com.iluwatar.objectmother.King} with the standard properties.
*/
public static King createSoberUnhappyKing() {
@ -38,6 +39,7 @@ public final class RoyaltyObjectMother {
/**
* Method of the object mother to create a drunk king.
*
* @return A drunk {@link com.iluwatar.objectmother.King}.
*/
public static King createDrunkKing() {
@ -48,6 +50,7 @@ public final class RoyaltyObjectMother {
/**
* Method to create a happy king.
*
* @return A happy {@link com.iluwatar.objectmother.King}.
*/
public static King createHappyKing() {
@ -58,6 +61,7 @@ public final class RoyaltyObjectMother {
/**
* Method to create a happy and drunk king.
*
* @return A drunk and happy {@link com.iluwatar.objectmother.King}.
*/
public static King createHappyDrunkKing() {
@ -69,6 +73,7 @@ public final class RoyaltyObjectMother {
/**
* Method to create a flirty queen.
*
* @return A flirty {@link com.iluwatar.objectmother.Queen}.
*/
public static Queen createFlirtyQueen() {
@ -79,6 +84,7 @@ public final class RoyaltyObjectMother {
/**
* Method to create a not flirty queen.
*
* @return A not flirty {@link com.iluwatar.objectmother.Queen}.
*/
public static Queen createNotFlirtyQueen() {

18
object-pool/src/main/java/com/iluwatar/object/pool/App.java
View File

@ -27,32 +27,30 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* When it is necessary to work with a large number of objects that are particularly expensive to
* instantiate and each object is only needed for a short period of time, the performance of an
* entire application may be adversely affected. An object pool design pattern may be deemed
* desirable in cases such as these.
* <p>
* The object pool design pattern creates a set of objects that may be reused. When a new object is
* needed, it is requested from the pool. If a previously prepared object is available it is
*
* <p>The object pool design pattern creates a set of objects that may be reused. When a new object
* is needed, it is requested from the pool. If a previously prepared object is available it is
* returned immediately, avoiding the instantiation cost. If no objects are present in the pool, a
* new item is created and returned. When the object has been used and is no longer needed, it is
* returned to the pool, allowing it to be used again in the future without repeating the
* computationally expensive instantiation process. It is important to note that once an object has
* been used and returned, existing references will become invalid.
* <p>
* In this example we have created {@link OliphauntPool} inheriting from generic {@link ObjectPool}.
* {@link Oliphaunt}s can be checked out from the pool and later returned to it. The pool tracks
* created instances and their status (available, inUse).
*
* <p>In this example we have created {@link OliphauntPool} inheriting from generic {@link
* ObjectPool}. {@link Oliphaunt}s can be checked out from the pool and later returned to it. The
* pool tracks created instances and their status (available, inUse).
*/
public class App {
private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
/**
* Program entry point
*
* Program entry point.
*
* @param args command line args
*/
public static void main(String[] args) {

5
object-pool/src/main/java/com/iluwatar/object/pool/ObjectPool.java
View File

@ -27,7 +27,8 @@ import java.util.HashSet;
import java.util.Set;
/**
* Generic object pool
* Generic object pool.
*
* @param <T> Type T of Object in the Pool
*/
public abstract class ObjectPool<T> {
@ -38,7 +39,7 @@ public abstract class ObjectPool<T> {
protected abstract T create();
/**
* Checkout object from pool
* Checkout object from pool.
*/
public synchronized T checkOut() {
if (available.isEmpty()) {

6
object-pool/src/main/java/com/iluwatar/object/pool/Oliphaunt.java
View File

@ -26,9 +26,7 @@ package com.iluwatar.object.pool;
import java.util.concurrent.atomic.AtomicInteger;
/**
*
* Oliphaunts are expensive to create
*
* Oliphaunts are expensive to create.
*/
public class Oliphaunt {
@ -37,7 +35,7 @@ public class Oliphaunt {
private final int id;
/**
* Constructor
* Constructor.
*/
public Oliphaunt() {
id = counter.incrementAndGet();

4
object-pool/src/main/java/com/iluwatar/object/pool/OliphauntPool.java
View File

@ -24,9 +24,7 @@
package com.iluwatar.object.pool;
/**
*
* Oliphaunt object pool
*
* Oliphaunt object pool.
*/
public class OliphauntPool extends ObjectPool<Oliphaunt> {

26
observer/src/main/java/com/iluwatar/observer/App.java
View File

@ -30,25 +30,23 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* The Observer pattern is a software design pattern in which an object, called the subject,
* maintains a list of its dependents, called observers, and notifies them automatically of any
* state changes, usually by calling one of their methods. It is mainly used to implement
* distributed event handling systems. The Observer pattern is also a key part in the familiar
* model–view–controller (MVC) architectural pattern. The Observer pattern is implemented in
* numerous programming libraries and systems, including almost all GUI toolkits.
* <p>
* In this example {@link Weather} has a state that can be observed. The {@link Orcs} and
* {@link Hobbits} register as observers and receive notifications when the {@link Weather} changes.
*
*
* <p>In this example {@link Weather} has a state that can be observed. The {@link Orcs} and {@link
* Hobbits} register as observers and receive notifications when the {@link Weather} changes.
*/
public class App {
private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
/**
* Program entry point
*
* Program entry point.
*
* @param args command line args
*/
public static void main(String[] args) {
@ -64,13 +62,13 @@ public class App {
// Generic observer inspired by Java Generics and Collection by Naftalin & Wadler
LOGGER.info("--Running generic version--");
GWeather gWeather = new GWeather();
gWeather.addObserver(new GOrcs());
gWeather.addObserver(new GHobbits());
GWeather genericWeather = new GWeather();
genericWeather.addObserver(new GOrcs());
genericWeather.addObserver(new GHobbits());
gWeather.timePasses();
gWeather.timePasses();
gWeather.timePasses();
gWeather.timePasses();
genericWeather.timePasses();
genericWeather.timePasses();
genericWeather.timePasses();
genericWeather.timePasses();
}
}

4
observer/src/main/java/com/iluwatar/observer/Hobbits.java
View File

@ -27,9 +27,7 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* Hobbits
*
* Hobbits.
*/
public class Hobbits implements WeatherObserver {

4
observer/src/main/java/com/iluwatar/observer/Orcs.java
View File

@ -27,9 +27,7 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* Orcs
*
* Orcs.
*/
public class Orcs implements WeatherObserver {

9
observer/src/main/java/com/iluwatar/observer/Weather.java
View File

@ -23,17 +23,14 @@
package com.iluwatar.observer;
import java.util.ArrayList;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.ArrayList;
import java.util.List;
/**
*
* Weather can be observed by implementing {@link WeatherObserver} interface and registering as
* listener.
*
*/
public class Weather {
@ -56,7 +53,7 @@ public class Weather {
}
/**
* Makes time pass for weather
* Makes time pass for weather.
*/
public void timePasses() {
WeatherType[] enumValues = WeatherType.values();

2
observer/src/main/java/com/iluwatar/observer/WeatherObserver.java
View File

@ -24,9 +24,7 @@
package com.iluwatar.observer;
/**
*
* Observer interface.
*
*/
public interface WeatherObserver {

4
observer/src/main/java/com/iluwatar/observer/WeatherType.java
View File

@ -24,9 +24,7 @@
package com.iluwatar.observer;
/**
*
* WeatherType enumeration
*
* WeatherType enumeration.
*/
public enum WeatherType {

4
observer/src/main/java/com/iluwatar/observer/generic/GHobbits.java
View File

@ -28,9 +28,7 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* GHobbits
*
* GHobbits.
*/
public class GHobbits implements Race {

4
observer/src/main/java/com/iluwatar/observer/generic/GOrcs.java
View File

@ -28,9 +28,7 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* GOrcs
*
* GOrcs.
*/
public class GOrcs implements Race {

6
observer/src/main/java/com/iluwatar/observer/generic/GWeather.java
View File

@ -28,9 +28,7 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* GWeather
*
* GWeather.
*/
public class GWeather extends Observable<GWeather, Race, WeatherType> {
@ -43,7 +41,7 @@ public class GWeather extends Observable<GWeather, Race, WeatherType> {
}
/**
* Makes time pass for weather
* Makes time pass for weather.
*/
public void timePasses() {
WeatherType[] enumValues = WeatherType.values();

4
observer/src/main/java/com/iluwatar/observer/generic/Observable.java
View File

@ -27,7 +27,7 @@ import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
/**
* Generic observer inspired by Java Generics and Collection by {@literal Naftalin & Wadler}
* Generic observer inspired by Java Generics and Collection by {@literal Naftalin & Wadler}.
*
* @param <S> Subject
* @param <O> Observer
@ -50,7 +50,7 @@ public abstract class Observable<S extends Observable<S, O, A>, O extends Observ
}
/**
* Notify observers
* Notify observers.
*/
@SuppressWarnings("unchecked")
public void notifyObservers(A argument) {

3
observer/src/main/java/com/iluwatar/observer/generic/Observer.java
View File

@ -24,7 +24,8 @@
package com.iluwatar.observer.generic;
/**
* Observer
* Observer.
*
* @param <S> Observable
* @param <O> Observer
* @param <A> Action

4
observer/src/main/java/com/iluwatar/observer/generic/Race.java
View File

@ -26,9 +26,7 @@ package com.iluwatar.observer.generic;
import com.iluwatar.observer.WeatherType;
/**
*
* Race
*
* Race.
*/
public interface Race extends Observer<GWeather, Race, WeatherType> {
}

93
queue-load-leveling/src/main/java/com/iluwatar/queue/load/leveling/App.java
View File

@ -26,69 +26,69 @@ package com.iluwatar.queue.load.leveling;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* Many solutions in the cloud involve running tasks that invoke services. In this environment,
* if a service is subjected to intermittent heavy loads, it can cause performance or reliability issues.
* <p>
* A service could be a component that is part of the same solution as the tasks that utilize it, or it
* could be a third-party service providing access to frequently used resources such as a cache or a storage service.
* If the same service is utilized by a number of tasks running concurrently, it can be difficult to predict the
* volume of requests to which the service might be subjected at any given point in time.
* <p>
* We will build a queue-based-load-leveling to solve above problem.
* Refactor the solution and introduce a queue between the task and the service.
* The task and the service run asynchronously. The task posts a message containing the data required
* by the service to a queue. The queue acts as a buffer, storing the message until it is retrieved
* by the service. The service retrieves the messages from the queue and processes them.
* Requests from a number of tasks, which can be generated at a highly variable rate, can be passed
* to the service through the same message queue.
* <p>
* The queue effectively decouples the tasks from the service, and the service can handle the messages
* at its own pace irrespective of the volume of requests from concurrent tasks. Additionally,
* there is no delay to a task if the service is not available at the time it posts a message to the queue.
* <p>
* In this example we have a class {@link MessageQueue} to hold the message {@link Message} objects.
* All the worker threads {@link TaskGenerator} will submit the messages to the MessageQueue.
* The service executor class {@link ServiceExecutor} will pick up one task at a time from the Queue and
* execute them.
*
* Many solutions in the cloud involve running tasks that invoke services. In this environment, if a
* service is subjected to intermittent heavy loads, it can cause performance or reliability
* issues.
*
* <p>A service could be a component that is part of the same solution as the tasks that utilize
* it, or it could be a third-party service providing access to frequently used resources such as a
* cache or a storage service. If the same service is utilized by a number of tasks running
* concurrently, it can be difficult to predict the volume of requests to which the service might be
* subjected at any given point in time.
*
* <p>We will build a queue-based-load-leveling to solve above problem. Refactor the solution and
* introduce a queue between the task and the service. The task and the service run asynchronously.
* The task posts a message containing the data required by the service to a queue. The queue acts
* as a buffer, storing the message until it is retrieved by the service. The service retrieves the
* messages from the queue and processes them. Requests from a number of tasks, which can be
* generated at a highly variable rate, can be passed to the service through the same message
* queue.
*
* <p>The queue effectively decouples the tasks from the service, and the service can handle the
* messages at its own pace irrespective of the volume of requests from concurrent tasks.
* Additionally, there is no delay to a task if the service is not available at the time it posts a
* message to the queue.
*
* <p>In this example we have a class {@link MessageQueue} to hold the message {@link Message}
* objects. All the worker threads {@link TaskGenerator} will submit the messages to the
* MessageQueue. The service executor class {@link ServiceExecutor} will pick up one task at a time
* from the Queue and execute them.
*/
public class App {
private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
//Executor shut down time limit.
private static final int SHUTDOWN_TIME = 15;
/**
* Program entry point
*
* Program entry point.
*
* @param args command line args
*/
public static void main(String[] args) {
// An Executor that provides methods to manage termination and methods that can
// produce a Future for tracking progress of one or more asynchronous tasks.
ExecutorService executor = null;
try {
// Create a MessageQueue object.
MessageQueue msgQueue = new MessageQueue();
LOGGER.info("Submitting TaskGenerators and ServiceExecutor threads.");
// Create three TaskGenerator threads. Each of them will submit different number of jobs.
Runnable taskRunnable1 = new TaskGenerator(msgQueue, 5);
Runnable taskRunnable2 = new TaskGenerator(msgQueue, 1);
Runnable taskRunnable3 = new TaskGenerator(msgQueue, 2);
final Runnable taskRunnable1 = new TaskGenerator(msgQueue, 5);
final Runnable taskRunnable2 = new TaskGenerator(msgQueue, 1);
final Runnable taskRunnable3 = new TaskGenerator(msgQueue, 2);
// Create e service which should process the submitted jobs.
Runnable srvRunnable = new ServiceExecutor(msgQueue);
final Runnable srvRunnable = new ServiceExecutor(msgQueue);
// Create a ThreadPool of 2 threads and
// submit all Runnable task for execution to executor..
@ -96,17 +96,18 @@ public class App {
executor.submit(taskRunnable1);
executor.submit(taskRunnable2);
executor.submit(taskRunnable3);
// submitting serviceExecutor thread to the Executor service.
executor.submit(srvRunnable);
// Initiates an orderly shutdown.
LOGGER.info("Intiating shutdown. Executor will shutdown only after all the Threads are completed.");
LOGGER.info("Initiating shutdown."
+ " Executor will shutdown only after all the Threads are completed.");
executor.shutdown();
// Wait for SHUTDOWN_TIME seconds for all the threads to complete
// their tasks and then shut down the executor and then exit.
if ( !executor.awaitTermination(SHUTDOWN_TIME, TimeUnit.SECONDS) ) {
if (!executor.awaitTermination(SHUTDOWN_TIME, TimeUnit.SECONDS)) {
LOGGER.info("Executor was shut down and Exiting.");
executor.shutdownNow();
}

9
queue-load-leveling/src/main/java/com/iluwatar/queue/load/leveling/Message.java
View File

@ -24,12 +24,11 @@
package com.iluwatar.queue.load.leveling;
/**
* Message class with only one parameter.
*
*/
* Message class with only one parameter.
*/
public class Message {
private final String msg;
// Parameter constructor.
public Message(String msg) {
this.msg = msg;
@ -39,7 +38,7 @@ public class Message {
public String getMsg() {
return msg;
}
@Override
public String toString() {
return msg;

28
queue-load-leveling/src/main/java/com/iluwatar/queue/load/leveling/MessageQueue.java
View File

@ -25,30 +25,27 @@ package com.iluwatar.queue.load.leveling;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* MessageQueue class.
* In this class we will create a Blocking Queue and
* submit/retrieve all the messages from it.
* MessageQueue class. In this class we will create a Blocking Queue and submit/retrieve all the
* messages from it.
*/
public class MessageQueue {
private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
private final BlockingQueue<Message> blkQueue;
// Default constructor when called creates Blocking Queue object.
public MessageQueue() {
this.blkQueue = new ArrayBlockingQueue<Message>(1024);
}
/**
* All the TaskGenerator threads will call this method to insert the
* Messages in to the Blocking Queue.
* All the TaskGenerator threads will call this method to insert the Messages in to the Blocking
* Queue.
*/
public void submitMsg(Message msg) {
try {
@ -59,11 +56,10 @@ public class MessageQueue {
LOGGER.error(e.getMessage());
}
}
/**
* All the messages will be retrieved by the ServiceExecutor by
* calling this method and process them.
* Retrieves and removes the head of this queue, or returns null if this queue is empty.
* All the messages will be retrieved by the ServiceExecutor by calling this method and process
* them. Retrieves and removes the head of this queue, or returns null if this queue is empty.
*/
public Message retrieveMsg() {
Message retrievedMsg = null;
@ -72,7 +68,7 @@ public class MessageQueue {
} catch (Exception e) {
LOGGER.error(e.getMessage());
}
return retrievedMsg;
}
}

6
queue-load-leveling/src/main/java/com/iluwatar/queue/load/leveling/ServiceExecutor.java
View File

@ -27,10 +27,8 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* ServiceExecuotr class.
* This class will pick up Messages one by one from
* the Blocking Queue and process them.
* ServiceExecuotr class. This class will pick up Messages one by one from the Blocking Queue and
* process them.
*/
public class ServiceExecutor implements Runnable {

4
queue-load-leveling/src/main/java/com/iluwatar/queue/load/leveling/Task.java
View File

@ -22,10 +22,10 @@
*/
package com.iluwatar.queue.load.leveling;
/**
* Task Interface.
*
*/
*/
public interface Task {
void submit(Message msg);
}

34
queue-load-leveling/src/main/java/com/iluwatar/queue/load/leveling/TaskGenerator.java
View File

@ -27,28 +27,26 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* TaskGenerator class.
* Each TaskGenerator thread will be a Worker which submit's messages to the queue.
* We need to mention the message count for each of the TaskGenerator threads.
*
*/
* TaskGenerator class. Each TaskGenerator thread will be a Worker which submit's messages to the
* queue. We need to mention the message count for each of the TaskGenerator threads.
*/
public class TaskGenerator implements Task, Runnable {
private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
// MessageQueue reference using which we will submit our messages.
private final MessageQueue msgQueue;
// Total message count that a TaskGenerator will submit.
private final int msgCount;
// Parameterized constructor.
public TaskGenerator(MessageQueue msgQueue, int msgCount) {
this.msgQueue = msgQueue;
this.msgCount = msgCount;
}
/**
* Submit messages to the Blocking Queue.
*/
@ -59,25 +57,25 @@ public class TaskGenerator implements Task, Runnable {
LOGGER.error(e.getMessage());
}
}
/**
* Each TaskGenerator thread will submit all the messages to the Queue.
* After every message submission TaskGenerator thread will sleep for 1 second.
* Each TaskGenerator thread will submit all the messages to the Queue. After every message
* submission TaskGenerator thread will sleep for 1 second.
*/
public void run() {
int count = this.msgCount;
try {
while (count > 0) {
String statusMsg = "Message-" + count + " submitted by " + Thread.currentThread().getName();
this.submit(new Message(statusMsg));
LOGGER.info(statusMsg);
// reduce the message count.
count--;
// Make the current thread to sleep after every Message submission.
Thread.sleep(1000);
}