From 9836790893e614f4bdcba5d83217331f06722858 Mon Sep 17 00:00:00 2001
From: Giovanni Di Grezia <xgiovio@gmail.com>
Date: Tue, 1 Apr 2014 18:10:49 +0200
Subject: [PATCH] Implementazione parziale Priority Queue

---
 exceptions/EmptyPriorityQueueException.java | 18 ++++++++++++++++++
 priorityqueue/Entry.java                    | 12 ++++++++++++
 priorityqueue/PriorityQueue.java            | 18 ++++++++++++++++++
 3 files changed, 48 insertions(+)
 create mode 100644 exceptions/EmptyPriorityQueueException.java
 create mode 100644 priorityqueue/Entry.java
 create mode 100644 priorityqueue/PriorityQueue.java

diff --git a/exceptions/EmptyPriorityQueueException.java b/exceptions/EmptyPriorityQueueException.java
new file mode 100644
index 0000000..754ef0b
--- /dev/null
+++ b/exceptions/EmptyPriorityQueueException.java
@@ -0,0 +1,18 @@
+package exceptions;
+
+/**
+ * Signals that the boundaries of a data structure have been illegally
+ * traversed (e.g. past the end of a list).
+ * @author Roberto Tamassia
+ */
+//Copyright (c) 2003 Brown University, Providence, RI
+//Additional modifications and methods by xgiovio
+
+public class EmptyPriorityQueueException extends RuntimeException {
+  public EmptyPriorityQueueException(String message) {
+    super (message);
+  }
+    public EmptyPriorityQueueException() {
+        super ("EmptyPriorityQueueException");
+    }
+}
diff --git a/priorityqueue/Entry.java b/priorityqueue/Entry.java
new file mode 100644
index 0000000..94d2703
--- /dev/null
+++ b/priorityqueue/Entry.java
@@ -0,0 +1,12 @@
+package priorityqueue;
+
+/**
+ * Created with xgiovio.macbookair.
+ * User: xgiovio
+ * Date: 01/04/14
+ * Time: 16:27
+ */
+public interface Entry<K,V> {
+    public K getKey();
+    public V getValue();
+}
diff --git a/priorityqueue/PriorityQueue.java b/priorityqueue/PriorityQueue.java
new file mode 100644
index 0000000..361fec4
--- /dev/null
+++ b/priorityqueue/PriorityQueue.java
@@ -0,0 +1,18 @@
+package priorityqueue;
+
+import exceptions.EmptyPriorityQueueException;
+import java.security.InvalidKeyException;
+
+/**
+ * Created with xgiovio.macbookair.
+ * User: xgiovio
+ * Date: 01/04/14
+ * Time: 16:29
+ */
+public interface PriorityQueue<K,V> {
+    public int size();
+    public boolean isEmpty();
+    public Entry<K,V> min() throws EmptyPriorityQueueException;
+    public Entry<K,V> insert(K key, V value) throws InvalidKeyException;
+    public Entry<K,V> removeMin() throws EmptyPriorityQueueException;
+}