Implement ResultSetId class to represent result sets.

git-svn-id: https://hyracks.googlecode.com/svn/branches/fullstack_hyracks_result_distribution@2530 123451ca-8445-de46-9d55-352943316053
diff --git a/hyracks/hyracks-api/src/main/java/edu/uci/ics/hyracks/api/dataset/ResultSetId.java b/hyracks/hyracks-api/src/main/java/edu/uci/ics/hyracks/api/dataset/ResultSetId.java
new file mode 100644
index 0000000..ae38ef3
--- /dev/null
+++ b/hyracks/hyracks-api/src/main/java/edu/uci/ics/hyracks/api/dataset/ResultSetId.java
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.api.dataset;
+
+import java.io.Serializable;
+
+public class ResultSetId implements Serializable {
+    private static final long serialVersionUID = 1L;
+
+    private final long id;
+
+    public ResultSetId(long id) {
+        this.id = id;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    @Override
+    public int hashCode() {
+        return (int) id;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (o == this) {
+            return true;
+        }
+        if (!(o instanceof ResultSetId)) {
+            return false;
+        }
+        return ((ResultSetId) o).id == id;
+    }
+
+    @Override
+    public String toString() {
+        return "RSID:" + id;
+    }
+}