Adding javadocs

Author: tandonks

server/src/main/java/org/opensearch/search/aggregations/metrics/ScriptedAvg.java

@@ -6,6 +6,30 @@
  * compatible open source license.
  */
 
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you 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 at
+ *
+ *    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.
+ */
+
+/*
+ * Modifications Copyright OpenSearch Contributors. See
+ * GitHub history for details.
+ */
+
 package org.opensearch.search.aggregations.metrics;
 
 import org.opensearch.core.common.io.stream.StreamInput;
@@ -14,15 +38,29 @@
 
 import java.io.IOException;
 
+/**
+ * Represents a scripted average calculation containing a sum and count.
+ *
+ * @opensearch.internal
+ */
 public class ScriptedAvg implements Writeable {
     private double sum;
     private long count;
 
+    /**
+     * Constructor for ScriptedAvg
+     *
+     * @param sum   The sum of values
+     * @param count The count of values
+     */
     public ScriptedAvg(double sum, long count) {
         this.sum = sum;
         this.count = count;
     }
 
+    /**
+     * Read from a stream.
+     */
     public ScriptedAvg(StreamInput in) throws IOException {
         this.sum = in.readDouble();
         this.count = in.readLong();