/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF 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.
 */

package org.apache.spark.sql.sources.v2.reader.streaming;

import org.apache.spark.sql.sources.v2.reader.ReadSupport;

/**
 * A base interface for streaming read support. This is package private and is invisible to data
 * sources. Data sources should implement concrete streaming read support interfaces:
 * {@link MicroBatchReadSupport} or {@link ContinuousReadSupport}.
 */
interface StreamingReadSupport extends ReadSupport {

  /**
   * Returns the initial offset for a streaming query to start reading from. Note that the
   * streaming data source should not assume that it will start reading from its initial offset:
   * if Spark is restarting an existing query, it will restart from the check-pointed offset rather
   * than the initial one.
   */
  Offset initialOffset();

  /**
   * Deserialize a JSON string into an Offset of the implementation-defined offset type.
   *
   * @throws IllegalArgumentException if the JSON does not encode a valid offset for this reader
   */
  Offset deserializeOffset(String json);

  /**
   * Informs the source that Spark has completed processing all data for offsets less than or
   * equal to `end` and will only request offsets greater than `end` in the future.
   */
  void commit(Offset end);
}

@@ -854,16 +854,73 @@
 aming;%0A%0A
+import com.google.common.annotations.VisibleForTesting;%0A%0A
 import o
@@ -1026,69 +1026,8 @@
 ort.
- This is package private and is invisible to data%0A * sources.
  Dat
@@ -1063,32 +1063,35 @@
 ncrete streaming
+%0A *
  read support in
@@ -1099,19 +1099,16 @@
 erfaces:
-%0A *
  %7B@link 
@@ -1166,18 +1166,86 @@
 ort%7D.%0A *
-/%0A
+ This is exposed for a testing purpose.%0A */%0A@VisibleForTesting%0Apublic 
 interfac

Make StreamingReadSupport public for maven testing