created tuple class

src/Tuple.java

@@ -0,0 +1,34 @@
+public class Tuple2<T1, T2> {
+
+    public final T1 item1;
+    public final T2 item2;
+
+    public Tuple2(T1 x, T2 y) {
+        this.item1 = x;
+        this.item2 = y;
+    }
+
+
+    @Override
+    public boolean equals(final Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (!(obj instanceof Tuple2))
+            return false;
+        final Tuple2<?, ?> other = (Tuple2<?, ?>) obj;
+        if (_1 == null) {
+            if (other._1 != null)
+                return false;
+        } else if (!_1.equals(other._1))
+            return false;
+        if (_2 == null) {
+            if (other._2 != null)
+                return false;
+        } else if (!_2.equals(other._2))
+            return false;
+        return true;
+    }
+
+}