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#107 Iterator example JavaDoc

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This commit is contained in:
Ilkka Seppala
2015-08-18 23:14:04 +03:00
parent 5831d3239d
commit 0d2e033df6
7 changed files with 212 additions and 188 deletions
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86
iterator/src/main/java/com/iluwatar/iterator/App.java
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@@ -1,41 +1,45 @@
package com.iluwatar.iterator;
/**
*
* Iterator (ItemIterator) adds abstraction layer on top of a collection
* (TreasureChest). This way the collection can change its internal
* implementation without affecting its clients.
*
*/
public class App {
public static void main(String[] args) {
TreasureChest chest = new TreasureChest();
ItemIterator ringIterator = chest.Iterator(ItemType.RING);
while (ringIterator.hasNext()) {
System.out.println(ringIterator.next());
}
System.out.println("----------");
ItemIterator potionIterator = chest.Iterator(ItemType.POTION);
while (potionIterator.hasNext()) {
System.out.println(potionIterator.next());
}
System.out.println("----------");
ItemIterator weaponIterator = chest.Iterator(ItemType.WEAPON);
while (weaponIterator.hasNext()) {
System.out.println(weaponIterator.next());
}
System.out.println("----------");
ItemIterator it = chest.Iterator(ItemType.ANY);
while (it.hasNext()) {
System.out.println(it.next());
}
}
}
package com.iluwatar.iterator;
/**
*
* Iterator ({@link ItemIterator}) adds abstraction layer on top of a collection
* ({@link TreasureChest}). This way the collection can change its internal
* implementation without affecting its clients.
*
*/
public class App {
/**
* Program entry point
* @param args command line args
*/
public static void main(String[] args) {
TreasureChest chest = new TreasureChest();
ItemIterator ringIterator = chest.Iterator(ItemType.RING);
while (ringIterator.hasNext()) {
System.out.println(ringIterator.next());
}
System.out.println("----------");
ItemIterator potionIterator = chest.Iterator(ItemType.POTION);
while (potionIterator.hasNext()) {
System.out.println(potionIterator.next());
}
System.out.println("----------");
ItemIterator weaponIterator = chest.Iterator(ItemType.WEAPON);
while (weaponIterator.hasNext()) {
System.out.println(weaponIterator.next());
}
System.out.println("----------");
ItemIterator it = chest.Iterator(ItemType.ANY);
while (it.hasNext()) {
System.out.println(it.next());
}
}
}

55
iterator/src/main/java/com/iluwatar/iterator/Item.java
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@@ -1,25 +1,30 @@
package com.iluwatar.iterator;
public class Item {
private ItemType type;
private String name;
public Item(ItemType type, String name) {
this.setType(type);
this.name = name;
}
@Override
public String toString() {
return name;
}
public ItemType getType() {
return type;
}
public void setType(ItemType type) {
this.type = type;
}
}
package com.iluwatar.iterator;
/**
*
* Item
*
*/
public class Item {
private ItemType type;
private String name;
public Item(ItemType type, String name) {
this.setType(type);
this.name = name;
}
@Override
public String toString() {
return name;
}
public ItemType getType() {
return type;
}
public void setType(ItemType type) {
this.type = type;
}
}

26
iterator/src/main/java/com/iluwatar/iterator/ItemIterator.java
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@@ -1,13 +1,13 @@
package com.iluwatar.iterator;
/**
*
* Iterator interface.
*
*/
public interface ItemIterator {
boolean hasNext();
Item next();
}
package com.iluwatar.iterator;
/**
*
* ItemIterator interface.
*
*/
public interface ItemIterator {
boolean hasNext();
Item next();
}

19
iterator/src/main/java/com/iluwatar/iterator/ItemType.java
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@@ -1,7 +1,12 @@
package com.iluwatar.iterator;
public enum ItemType {
ANY, WEAPON, RING, POTION
}
package com.iluwatar.iterator;
/**
*
* ItemType enumeration
*
*/
public enum ItemType {
ANY, WEAPON, RING, POTION
}

78
iterator/src/main/java/com/iluwatar/iterator/TreasureChest.java
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@@ -1,39 +1,39 @@
package com.iluwatar.iterator;
import java.util.ArrayList;
import java.util.List;
/**
*
* Collection class.
*
*/
public class TreasureChest {
private List<Item> items;
public TreasureChest() {
items = new ArrayList<>();
items.add(new Item(ItemType.POTION, "Potion of courage"));
items.add(new Item(ItemType.RING, "Ring of shadows"));
items.add(new Item(ItemType.POTION, "Potion of wisdom"));
items.add(new Item(ItemType.POTION, "Potion of blood"));
items.add(new Item(ItemType.WEAPON, "Sword of silver +1"));
items.add(new Item(ItemType.POTION, "Potion of rust"));
items.add(new Item(ItemType.POTION, "Potion of healing"));
items.add(new Item(ItemType.RING, "Ring of armor"));
items.add(new Item(ItemType.WEAPON, "Steel halberd"));
items.add(new Item(ItemType.WEAPON, "Dagger of poison"));
}
ItemIterator Iterator(ItemType type) {
return new TreasureChestItemIterator(this, type);
}
public List<Item> getItems() {
ArrayList<Item> list = new ArrayList<>();
list.addAll(items);
return list;
}
}
package com.iluwatar.iterator;
import java.util.ArrayList;
import java.util.List;
/**
*
* TreasureChest, the collection class.
*
*/
public class TreasureChest {
private List<Item> items;
public TreasureChest() {
items = new ArrayList<>();
items.add(new Item(ItemType.POTION, "Potion of courage"));
items.add(new Item(ItemType.RING, "Ring of shadows"));
items.add(new Item(ItemType.POTION, "Potion of wisdom"));
items.add(new Item(ItemType.POTION, "Potion of blood"));
items.add(new Item(ItemType.WEAPON, "Sword of silver +1"));
items.add(new Item(ItemType.POTION, "Potion of rust"));
items.add(new Item(ItemType.POTION, "Potion of healing"));
items.add(new Item(ItemType.RING, "Ring of armor"));
items.add(new Item(ItemType.WEAPON, "Steel halberd"));
items.add(new Item(ItemType.WEAPON, "Dagger of poison"));
}
ItemIterator Iterator(ItemType type) {
return new TreasureChestItemIterator(this, type);
}
public List<Item> getItems() {
ArrayList<Item> list = new ArrayList<>();
list.addAll(items);
return list;
}
}

103
iterator/src/main/java/com/iluwatar/iterator/TreasureChestItemIterator.java
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@@ -1,49 +1,54 @@
package com.iluwatar.iterator;
import java.util.List;
public class TreasureChestItemIterator implements ItemIterator {
private TreasureChest chest;
private int idx;
private ItemType type;
public TreasureChestItemIterator(TreasureChest chest, ItemType type) {
this.chest = chest;
this.type = type;
this.idx = -1;
}
@Override
public boolean hasNext() {
return findNextIdx() != -1;
}
@Override
public Item next() {
idx = findNextIdx();
if (idx != -1) {
return chest.getItems().get(idx);
}
return null;
}
private int findNextIdx() {
List<Item> items = chest.getItems();
boolean found = false;
int tempIdx = idx;
while (!found) {
tempIdx++;
if (tempIdx >= items.size()) {
tempIdx = -1;
break;
}
if (type.equals(ItemType.ANY)
|| items.get(tempIdx).getType().equals(type)) {
break;
}
}
return tempIdx;
}
}
package com.iluwatar.iterator;
import java.util.List;
/**
*
* TreasureChestItemIterator
*
*/
public class TreasureChestItemIterator implements ItemIterator {
private TreasureChest chest;
private int idx;
private ItemType type;
public TreasureChestItemIterator(TreasureChest chest, ItemType type) {
this.chest = chest;
this.type = type;
this.idx = -1;
}
@Override
public boolean hasNext() {
return findNextIdx() != -1;
}
@Override
public Item next() {
idx = findNextIdx();
if (idx != -1) {
return chest.getItems().get(idx);
}
return null;
}
private int findNextIdx() {
List<Item> items = chest.getItems();
boolean found = false;
int tempIdx = idx;
while (!found) {
tempIdx++;
if (tempIdx >= items.size()) {
tempIdx = -1;
break;
}
if (type.equals(ItemType.ANY)
|| items.get(tempIdx).getType().equals(type)) {
break;
}
}
return tempIdx;
}
}

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