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#107 Improve JavaDoc for Observer example

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This commit is contained in:
Ilkka Seppala
2015-08-21 22:28:51 +03:00
parent 86c68f96e3
commit 520f81d62e
11 changed files with 208 additions and 156 deletions
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79
observer/src/main/java/com/iluwatar/observer/App.java
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@@ -1,38 +1,41 @@
package com.iluwatar.observer;
import com.iluwatar.observer.generic.GHobbits;
import com.iluwatar.observer.generic.GOrcs;
import com.iluwatar.observer.generic.GWeather;
/**
*
* Observer pattern defines one-to-many relationship between objects. The target
* object sends change notifications to its registered observers.
*
*/
public class App {
public static void main(String[] args) {
Weather weather = new Weather();
weather.addObserver(new Orcs());
weather.addObserver(new Hobbits());
weather.timePasses();
weather.timePasses();
weather.timePasses();
weather.timePasses();
// Generic observer inspired by Java Generics and Collection by Naftalin & Wadler
System.out.println("\n--Running generic version--");
GWeather gWeather = new GWeather();
gWeather.addObserver(new GOrcs());
gWeather.addObserver(new GHobbits());
gWeather.timePasses();
gWeather.timePasses();
gWeather.timePasses();
gWeather.timePasses();
}
}
package com.iluwatar.observer;
import com.iluwatar.observer.generic.GHobbits;
import com.iluwatar.observer.generic.GOrcs;
import com.iluwatar.observer.generic.GWeather;
/**
*
* Observer pattern defines one-to-many relationship between objects. The target
* object sends change notifications to its registered observers.
*
*/
public class App {
/**
* Program entry point
* @param args command line args
*/
public static void main(String[] args) {
Weather weather = new Weather();
weather.addObserver(new Orcs());
weather.addObserver(new Hobbits());
weather.timePasses();
weather.timePasses();
weather.timePasses();
weather.timePasses();
// Generic observer inspired by Java Generics and Collection by Naftalin & Wadler
System.out.println("\n--Running generic version--");
GWeather gWeather = new GWeather();
gWeather.addObserver(new GOrcs());
gWeather.addObserver(new GHobbits());
gWeather.timePasses();
gWeather.timePasses();
gWeather.timePasses();
gWeather.timePasses();
}
}

55
observer/src/main/java/com/iluwatar/observer/Hobbits.java
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@@ -1,25 +1,30 @@
package com.iluwatar.observer;
public class Hobbits implements WeatherObserver {
@Override
public void update(WeatherType currentWeather) {
switch (currentWeather) {
case COLD:
System.out.println("The hobbits are shivering in the cold weather.");
break;
case RAINY:
System.out.println("The hobbits look for cover from the rain.");
break;
case SUNNY:
System.out.println("The happy hobbits bade in the warm sun.");
break;
case WINDY:
System.out.println("The hobbits hold their hats tightly in the windy weather.");
break;
default:
break;
}
}
}
package com.iluwatar.observer;
/**
*
* Hobbits
*
*/
public class Hobbits implements WeatherObserver {
@Override
public void update(WeatherType currentWeather) {
switch (currentWeather) {
case COLD:
System.out.println("The hobbits are shivering in the cold weather.");
break;
case RAINY:
System.out.println("The hobbits look for cover from the rain.");
break;
case SUNNY:
System.out.println("The happy hobbits bade in the warm sun.");
break;
case WINDY:
System.out.println("The hobbits hold their hats tightly in the windy weather.");
break;
default:
break;
}
}
}

55
observer/src/main/java/com/iluwatar/observer/Orcs.java
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@@ -1,25 +1,30 @@
package com.iluwatar.observer;
public class Orcs implements WeatherObserver {
@Override
public void update(WeatherType currentWeather) {
switch (currentWeather) {
case COLD:
System.out.println("The orcs are freezing cold.");
break;
case RAINY:
System.out.println("The orcs are dripping wet.");
break;
case SUNNY:
System.out.println("The sun hurts the orcs' eyes.");
break;
case WINDY:
System.out.println("The orc smell almost vanishes in the wind.");
break;
default:
break;
}
}
}
package com.iluwatar.observer;
/**
*
* Orcs
*
*/
public class Orcs implements WeatherObserver {
@Override
public void update(WeatherType currentWeather) {
switch (currentWeather) {
case COLD:
System.out.println("The orcs are freezing cold.");
break;
case RAINY:
System.out.println("The orcs are dripping wet.");
break;
case SUNNY:
System.out.println("The sun hurts the orcs' eyes.");
break;
case WINDY:
System.out.println("The orc smell almost vanishes in the wind.");
break;
default:
break;
}
}
}

84
observer/src/main/java/com/iluwatar/observer/Weather.java
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@@ -1,42 +1,42 @@
package com.iluwatar.observer;
import java.util.ArrayList;
import java.util.List;
/**
*
* Weather can be observed by implementing WeatherObserver interface and
* registering as listener.
*
*/
public class Weather {
private WeatherType currentWeather;
private List<WeatherObserver> observers;
public Weather() {
observers = new ArrayList<>();
currentWeather = WeatherType.SUNNY;
}
public void addObserver(WeatherObserver obs) {
observers.add(obs);
}
public void removeObserver(WeatherObserver obs) {
observers.remove(obs);
}
public void timePasses() {
WeatherType[] enumValues = WeatherType.values();
currentWeather = enumValues[(currentWeather.ordinal() + 1) % enumValues.length];
System.out.println("The weather changed to " + currentWeather + ".");
notifyObservers();
}
private void notifyObservers() {
for (WeatherObserver obs : observers) {
obs.update(currentWeather);
}
}
}
package com.iluwatar.observer;
import java.util.ArrayList;
import java.util.List;
/**
*
* Weather can be observed by implementing {@link WeatherObserver} interface and
* registering as listener.
*
*/
public class Weather {
private WeatherType currentWeather;
private List<WeatherObserver> observers;
public Weather() {
observers = new ArrayList<>();
currentWeather = WeatherType.SUNNY;
}
public void addObserver(WeatherObserver obs) {
observers.add(obs);
}
public void removeObserver(WeatherObserver obs) {
observers.remove(obs);
}
public void timePasses() {
WeatherType[] enumValues = WeatherType.values();
currentWeather = enumValues[(currentWeather.ordinal() + 1) % enumValues.length];
System.out.println("The weather changed to " + currentWeather + ".");
notifyObservers();
}
private void notifyObservers() {
for (WeatherObserver obs : observers) {
obs.update(currentWeather);
}
}
}

29
observer/src/main/java/com/iluwatar/observer/WeatherType.java
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@@ -1,12 +1,17 @@
package com.iluwatar.observer;
public enum WeatherType {
SUNNY, RAINY, WINDY, COLD;
@Override
public String toString() {
return this.name().toLowerCase();
}
}
package com.iluwatar.observer;
/**
*
* WeatherType enumeration
*
*/
public enum WeatherType {
SUNNY, RAINY, WINDY, COLD;
@Override
public String toString() {
return this.name().toLowerCase();
}
}

5
observer/src/main/java/com/iluwatar/observer/generic/GHobbits.java
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@@ -2,6 +2,11 @@ package com.iluwatar.observer.generic;
import com.iluwatar.observer.WeatherType;
/**
*
* GHobbits
*
*/
public class GHobbits implements Race {
@Override
public void update(GWeather weather, WeatherType weatherType) {

6
observer/src/main/java/com/iluwatar/observer/generic/GOrcs.java
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@@ -2,7 +2,13 @@ package com.iluwatar.observer.generic;
import com.iluwatar.observer.WeatherType;
/**
*
* GOrcs
*
*/
public class GOrcs implements Race {
@Override
public void update(GWeather weather, WeatherType weatherType) {
switch (weatherType) {

5
observer/src/main/java/com/iluwatar/observer/generic/GWeather.java
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@@ -2,6 +2,11 @@ package com.iluwatar.observer.generic;
import com.iluwatar.observer.WeatherType;
/**
*
* GWeather
*
*/
public class GWeather extends Observable<GWeather, Race, WeatherType> {
private WeatherType currentWeather;

8
observer/src/main/java/com/iluwatar/observer/generic/Observer.java
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@@ -1,5 +1,13 @@
package com.iluwatar.observer.generic;
/**
*
* Observer
*
* @param <S>
* @param <O>
* @param <A>
*/
public interface Observer<S extends Observable<S, O, A>, O extends Observer<S, O, A>, A> {
void update(S subject, A argument);

5
observer/src/main/java/com/iluwatar/observer/generic/Race.java
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@@ -2,5 +2,10 @@ package com.iluwatar.observer.generic;
import com.iluwatar.observer.WeatherType;
/**
*
* Race
*
*/
public interface Race extends Observer<GWeather, Race, WeatherType> {
}

33
observer/src/test/java/com/iluwatar/observer/AppTest.java
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@@ -1,14 +1,19 @@
package com.iluwatar.observer;
import org.junit.Test;
import com.iluwatar.observer.App;
public class AppTest {
@Test
public void test() {
String[] args = {};
App.main(args);
}
}
package com.iluwatar.observer;
import org.junit.Test;
import com.iluwatar.observer.App;
/**
*
* Application test
*
*/
public class AppTest {
@Test
public void test() {
String[] args = {};
App.main(args);
}
}