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Merge pull request #280 from ankurkaushal/master

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Reformat Code According to Google Style Guide #224
This commit is contained in:
Ilkka Seppälä 2015-11-01 17:57:14 +02:00
commit 7d3483daad
12 changed files with 165 additions and 169 deletions
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63
observer/src/main/java/com/iluwatar/observer/App.java
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@ -6,45 +6,44 @@ import com.iluwatar.observer.generic.GWeather;
/** /**
* *
* The Observer pattern is a software design pattern in which an object, called * The Observer pattern is a software design pattern in which an object, called the subject,
* the subject, maintains a list of its dependents, called observers, and notifies * maintains a list of its dependents, called observers, and notifies them automatically of any
* them automatically of any state changes, usually by calling one of their methods. * state changes, usually by calling one of their methods. It is mainly used to implement
* It is mainly used to implement distributed event handling systems. The Observer * distributed event handling systems. The Observer pattern is also a key part in the familiar
* pattern is also a key part in the familiar model–view–controller (MVC) architectural * model–view–controller (MVC) architectural pattern. The Observer pattern is implemented in
* pattern. The Observer pattern is implemented in numerous programming libraries and * numerous programming libraries and systems, including almost all GUI toolkits.
* systems, including almost all GUI toolkits.
* <p> * <p>
* In this example {@link Weather} has a state that can be observed. The {@link Orcs} * In this example {@link Weather} has a state that can be observed. The {@link Orcs} and
* and {@link Hobbits} register as observers and receive notifications when the * {@link Hobbits} register as observers and receive notifications when the {@link Weather} changes.
* {@link Weather} changes.
* *
*/ */
public class App { public class App {
/** /**
* Program entry point * Program entry point
* @param args command line args *
*/ * @param args command line args
public static void main(String[] args) { */
public static void main(String[] args) {
Weather weather = new Weather(); Weather weather = new Weather();
weather.addObserver(new Orcs()); weather.addObserver(new Orcs());
weather.addObserver(new Hobbits()); weather.addObserver(new Hobbits());
weather.timePasses(); weather.timePasses();
weather.timePasses(); weather.timePasses();
weather.timePasses(); weather.timePasses();
weather.timePasses(); weather.timePasses();
// Generic observer inspired by Java Generics and Collection by Naftalin & Wadler // Generic observer inspired by Java Generics and Collection by Naftalin & Wadler
System.out.println("\n--Running generic version--"); System.out.println("\n--Running generic version--");
GWeather gWeather = new GWeather(); GWeather gWeather = new GWeather();
gWeather.addObserver(new GOrcs()); gWeather.addObserver(new GOrcs());
gWeather.addObserver(new GHobbits()); gWeather.addObserver(new GHobbits());
gWeather.timePasses(); gWeather.timePasses();
gWeather.timePasses(); gWeather.timePasses();
gWeather.timePasses(); gWeather.timePasses();
gWeather.timePasses(); gWeather.timePasses();
} }
} }

39
observer/src/main/java/com/iluwatar/observer/Hobbits.java
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@ -7,24 +7,23 @@ package com.iluwatar.observer;
*/ */
public class Hobbits implements WeatherObserver { public class Hobbits implements WeatherObserver {
@Override @Override
public void update(WeatherType currentWeather) { public void update(WeatherType currentWeather) {
switch (currentWeather) { switch (currentWeather) {
case COLD: case COLD:
System.out.println("The hobbits are shivering in the cold weather."); System.out.println("The hobbits are shivering in the cold weather.");
break; break;
case RAINY: case RAINY:
System.out.println("The hobbits look for cover from the rain."); System.out.println("The hobbits look for cover from the rain.");
break; break;
case SUNNY: case SUNNY:
System.out.println("The happy hobbits bade in the warm sun."); System.out.println("The happy hobbits bade in the warm sun.");
break; break;
case WINDY: case WINDY:
System.out.println("The hobbits hold their hats tightly in the windy weather."); System.out.println("The hobbits hold their hats tightly in the windy weather.");
break; break;
default: default:
break; break;
} }
} }
} }

39
observer/src/main/java/com/iluwatar/observer/Orcs.java
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@ -7,24 +7,23 @@ package com.iluwatar.observer;
*/ */
public class Orcs implements WeatherObserver { public class Orcs implements WeatherObserver {
@Override @Override
public void update(WeatherType currentWeather) { public void update(WeatherType currentWeather) {
switch (currentWeather) { switch (currentWeather) {
case COLD: case COLD:
System.out.println("The orcs are freezing cold."); System.out.println("The orcs are freezing cold.");
break; break;
case RAINY: case RAINY:
System.out.println("The orcs are dripping wet."); System.out.println("The orcs are dripping wet.");
break; break;
case SUNNY: case SUNNY:
System.out.println("The sun hurts the orcs' eyes."); System.out.println("The sun hurts the orcs' eyes.");
break; break;
case WINDY: case WINDY:
System.out.println("The orc smell almost vanishes in the wind."); System.out.println("The orc smell almost vanishes in the wind.");
break; break;
default: default:
break; break;
} }
} }
} }

50
observer/src/main/java/com/iluwatar/observer/Weather.java
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@ -5,38 +5,38 @@ import java.util.List;
/** /**
* *
* Weather can be observed by implementing {@link WeatherObserver} interface and * Weather can be observed by implementing {@link WeatherObserver} interface and registering as
* registering as listener. * listener.
* *
*/ */
public class Weather { public class Weather {
private WeatherType currentWeather; private WeatherType currentWeather;
private List<WeatherObserver> observers; private List<WeatherObserver> observers;
public Weather() { public Weather() {
observers = new ArrayList<>(); observers = new ArrayList<>();
currentWeather = WeatherType.SUNNY; currentWeather = WeatherType.SUNNY;
} }
public void addObserver(WeatherObserver obs) { public void addObserver(WeatherObserver obs) {
observers.add(obs); observers.add(obs);
} }
public void removeObserver(WeatherObserver obs) { public void removeObserver(WeatherObserver obs) {
observers.remove(obs); observers.remove(obs);
} }
public void timePasses() { public void timePasses() {
WeatherType[] enumValues = WeatherType.values(); WeatherType[] enumValues = WeatherType.values();
currentWeather = enumValues[(currentWeather.ordinal() + 1) % enumValues.length]; currentWeather = enumValues[(currentWeather.ordinal() + 1) % enumValues.length];
System.out.println("The weather changed to " + currentWeather + "."); System.out.println("The weather changed to " + currentWeather + ".");
notifyObservers(); notifyObservers();
} }
private void notifyObservers() { private void notifyObservers() {
for (WeatherObserver obs : observers) { for (WeatherObserver obs : observers) {
obs.update(currentWeather); obs.update(currentWeather);
} }
} }
} }

2
observer/src/main/java/com/iluwatar/observer/WeatherObserver.java
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@ -7,6 +7,6 @@ package com.iluwatar.observer;
*/ */
public interface WeatherObserver { public interface WeatherObserver {
void update(WeatherType currentWeather); void update(WeatherType currentWeather);
} }

11
observer/src/main/java/com/iluwatar/observer/WeatherType.java
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@ -7,11 +7,10 @@ package com.iluwatar.observer;
*/ */
public enum WeatherType { public enum WeatherType {
SUNNY, RAINY, WINDY, COLD; SUNNY, RAINY, WINDY, COLD;
@Override
public String toString() {
return this.name().toLowerCase();
}
@Override
public String toString() {
return this.name().toLowerCase();
}
} }

36
observer/src/main/java/com/iluwatar/observer/generic/GHobbits.java
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@ -8,23 +8,23 @@ import com.iluwatar.observer.WeatherType;
* *
*/ */
public class GHobbits implements Race { public class GHobbits implements Race {
@Override @Override
public void update(GWeather weather, WeatherType weatherType) { public void update(GWeather weather, WeatherType weatherType) {
switch (weatherType) { switch (weatherType) {
case COLD: case COLD:
System.out.println("The hobbits are shivering in the cold weather."); System.out.println("The hobbits are shivering in the cold weather.");
break; break;
case RAINY: case RAINY:
System.out.println("The hobbits look for cover from the rain."); System.out.println("The hobbits look for cover from the rain.");
break; break;
case SUNNY: case SUNNY:
System.out.println("The happy hobbits bade in the warm sun."); System.out.println("The happy hobbits bade in the warm sun.");
break; break;
case WINDY: case WINDY:
System.out.println("The hobbits hold their hats tightly in the windy weather."); System.out.println("The hobbits hold their hats tightly in the windy weather.");
break; break;
default: default:
break; break;
}
} }
}
} }

38
observer/src/main/java/com/iluwatar/observer/generic/GOrcs.java
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@ -8,24 +8,24 @@ import com.iluwatar.observer.WeatherType;
* *
*/ */
public class GOrcs implements Race { public class GOrcs implements Race {
@Override @Override
public void update(GWeather weather, WeatherType weatherType) { public void update(GWeather weather, WeatherType weatherType) {
switch (weatherType) { switch (weatherType) {
case COLD: case COLD:
System.out.println("The orcs are freezing cold."); System.out.println("The orcs are freezing cold.");
break; break;
case RAINY: case RAINY:
System.out.println("The orcs are dripping wet."); System.out.println("The orcs are dripping wet.");
break; break;
case SUNNY: case SUNNY:
System.out.println("The sun hurts the orcs' eyes."); System.out.println("The sun hurts the orcs' eyes.");
break; break;
case WINDY: case WINDY:
System.out.println("The orc smell almost vanishes in the wind."); System.out.println("The orc smell almost vanishes in the wind.");
break; break;
default: default:
break; break;
}
} }
}
} }

20
observer/src/main/java/com/iluwatar/observer/generic/GWeather.java
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@ -9,16 +9,16 @@ import com.iluwatar.observer.WeatherType;
*/ */
public class GWeather extends Observable<GWeather, Race, WeatherType> { public class GWeather extends Observable<GWeather, Race, WeatherType> {
private WeatherType currentWeather; private WeatherType currentWeather;
public GWeather() { public GWeather() {
currentWeather = WeatherType.SUNNY; currentWeather = WeatherType.SUNNY;
} }
public void timePasses() { public void timePasses() {
WeatherType[] enumValues = WeatherType.values(); WeatherType[] enumValues = WeatherType.values();
currentWeather = enumValues[(currentWeather.ordinal() + 1) % enumValues.length]; currentWeather = enumValues[(currentWeather.ordinal() + 1) % enumValues.length];
System.out.println("The weather changed to " + currentWeather + "."); System.out.println("The weather changed to " + currentWeather + ".");
notifyObservers(currentWeather); notifyObservers(currentWeather);
} }
} }

24
observer/src/main/java/com/iluwatar/observer/generic/Observable.java
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@ -12,20 +12,20 @@ import java.util.concurrent.CopyOnWriteArrayList;
*/ */
public abstract class Observable<S extends Observable<S, O, A>, O extends Observer<S, O, A>, A> { public abstract class Observable<S extends Observable<S, O, A>, O extends Observer<S, O, A>, A> {
protected List<O> observers; protected List<O> observers;
public Observable() { public Observable() {
this.observers = new CopyOnWriteArrayList<>(); this.observers = new CopyOnWriteArrayList<>();
} }
public void addObserver(O observer) { public void addObserver(O observer) {
this.observers.add(observer); this.observers.add(observer);
} }
@SuppressWarnings("unchecked") @SuppressWarnings("unchecked")
public void notifyObservers(A argument) { public void notifyObservers(A argument) {
for (O observer : observers) { for (O observer : observers) {
observer.update((S) this, argument); observer.update((S) this, argument);
}
} }
}
} }

2
observer/src/main/java/com/iluwatar/observer/generic/Observer.java
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@ -10,5 +10,5 @@ package com.iluwatar.observer.generic;
*/ */
public interface Observer<S extends Observable<S, O, A>, O extends Observer<S, O, A>, A> { public interface Observer<S extends Observable<S, O, A>, O extends Observer<S, O, A>, A> {
void update(S subject, A argument); void update(S subject, A argument);
} }

10
observer/src/test/java/com/iluwatar/observer/AppTest.java
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@ -11,9 +11,9 @@ import com.iluwatar.observer.App;
*/ */
public class AppTest { public class AppTest {
@Test @Test
public void test() { public void test() {
String[] args = {}; String[] args = {};
App.main(args); App.main(args);
} }
} }