Iterator Pattern

Java

by techbard 2016. 7. 18. 16:57

# Item.java

import java.util.Iterator;

public class Item implements Iterable<String> {
private String[] items;
private int index;

public Item() {
this.items = new String[10];
this.index = 0;
}

public void add(String item) {
if (index == items.length) {
String[] largerItems = new String[items.length + 5];
System.arraycopy(items, 0, largerItems, 0, items.length);
items = largerItems;
largerItems = null;
}

items[this.index] = item;
this.index++;
}

@Override
public Iterator<String> iterator() {
Iterator<String> itr = new Iterator<String>() {
private int currentIndex = 0;

@Override
public boolean hasNext() {
return currentIndex < items.length && items[currentIndex] != null;
}

@Override
public String next() {
return items[currentIndex++];
}
};

return itr;
}
}

# Main.java

import java.util.Iterator;

public class Main {
public static void main(String[] args) {
Item item = new Item();

item.add("a");
item.add("b");
item.add("c");

Iterator<String> itemIterator = item.iterator();

while (itemIterator.hasNext()) {
System.out.println(itemIterator.next());
}
}
}