#108 Consistent package naming throughout the examples

double-checked-locking/src/main/java/com/iluwatar/doublechecked/locking/App.java

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+package com.iluwatar.doublechecked.locking;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+/**
+ * 
+ * In Inventory we store the items with a given size. However, we do not store
+ * more items than the inventory size. To address concurrent access problems we
+ * use double checked locking to add item to inventory. In this method, the
+ * thread which gets the lock first adds the item.
+ */
+public class App {
+
+	public static void main(String[] args) {
+		final Inventory inventory = new Inventory(1000);
+		ExecutorService executorService = Executors.newFixedThreadPool(3);
+		for (int i = 0; i < 3; i++) {
+			executorService.execute(new Runnable() {
+				@Override
+				public void run() {
+					while (inventory.addItem(new Item()))
+						;
+				}
+			});
+		}
+	}
+}

double-checked-locking/src/main/java/com/iluwatar/doublechecked/locking/Inventory.java

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+package com.iluwatar.doublechecked.locking;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+public class Inventory {
+
+	private int inventorySize;
+	private List<Item> items;
+	private Lock lock = new ReentrantLock();
+
+	public Inventory(int inventorySize) {
+		this.inventorySize = inventorySize;
+		this.items = new ArrayList<Item>(inventorySize);
+	}
+
+	public boolean addItem(Item item) {
+		if (items.size() < inventorySize) {
+			lock.lock();
+			try {
+				if (items.size() < inventorySize) {
+					items.add(item);
+					System.out.println(Thread.currentThread());
+					return true;
+				}
+			} finally {
+				lock.unlock();
+			}
+		}
+		return false;
+	}
+
+}

double-checked-locking/src/main/java/com/iluwatar/doublechecked/locking/Item.java

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+package com.iluwatar.doublechecked.locking;
+
+public class Item {
+	String name;
+	int level;
+}