data_structures_free

net/datastructures/Map.java

@@ -0,0 +1,36 @@
+package net.datastructures;
+/**
+ * An interface for a map which binds a key uniquely to a value.
+ * @author Michael Goodrich
+ */
+//begin#fragment Map
+// A simple Map interface
+public interface Map<K,V> {
+  /** Returns the number of items in the map. */ 
+  public int size();
+  /** Returns whether the map is empty. */
+  public boolean isEmpty();
+  /** 
+    * If there is an entry with the specified key, replaces the value of
+    * this entry with the specified value and returns the old value. Else,
+    * adds a new entry with the specified key and value and returns null.
+    */
+  public V put(K key, V value) throws InvalidKeyException;
+  /** 
+   * Returns the value of the entry containing the given key.  Returns
+   * null if no such entry exists.
+   */
+  public V get(K key) throws InvalidKeyException;
+  /** 
+   * If there is an entry with the specified key, removes this entry and
+   * returns its value. Else, returns null.
+   */
+  public V remove(K key) throws InvalidKeyException;
+  /** Returns an iterable object containing all the keys in the map. */
+  public Iterable<K> keySet();
+  /** Returns an iterable object containing all the values in the map. */
+  public Iterable<V> values();
+  /** Returns an iterable object containing all the entries in the map. */
+  public Iterable<Entry<K,V>> entrySet();  
+}
+//end#fragment Map