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diff --git a/icing/index/numeric/posting-list-integer-index-data-accessor.h b/icing/index/numeric/posting-list-integer-index-data-accessor.h
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+// Copyright (C) 2022 Google LLC
+//
+// 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 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.
+
+#ifndef ICING_INDEX_NUMERIC_POSTING_LIST_INTEGER_INDEX_DATA_ACCESSOR_H_
+#define ICING_INDEX_NUMERIC_POSTING_LIST_INTEGER_INDEX_DATA_ACCESSOR_H_
+
+#include <cstdint>
+#include <memory>
+#include <vector>
+
+#include "icing/text_classifier/lib3/utils/base/status.h"
+#include "icing/text_classifier/lib3/utils/base/statusor.h"
+#include "icing/file/posting_list/flash-index-storage.h"
+#include "icing/file/posting_list/posting-list-accessor.h"
+#include "icing/file/posting_list/posting-list-identifier.h"
+#include "icing/file/posting_list/posting-list-used.h"
+#include "icing/index/numeric/integer-index-data.h"
+#include "icing/index/numeric/posting-list-used-integer-index-data-serializer.h"
+
+namespace icing {
+namespace lib {
+
+// TODO(b/259743562): Refactor PostingListAccessor derived classes
+
+// This class is used to provide a simple abstraction for adding integer index
+// data to posting lists. PostingListIntegerIndexDataAccessor handles:
+// 1) selection of properly-sized posting lists for the accumulated integer
+//    index data during Finalize()
+// 2) chaining of max-sized posting lists.
+class PostingListIntegerIndexDataAccessor : public PostingListAccessor {
+ public:
+  // Creates an empty PostingListIntegerIndexDataAccessor.
+  //
+  // RETURNS:
+  //   - On success, a valid instance of PostingListIntegerIndexDataAccessor
+  //   - INVALID_ARGUMENT error if storage has an invalid block_size.
+  static libtextclassifier3::StatusOr<
+      std::unique_ptr<PostingListIntegerIndexDataAccessor>>
+  Create(FlashIndexStorage* storage,
+         PostingListUsedIntegerIndexDataSerializer* serializer);
+
+  // Create a PostingListIntegerIndexDataAccessor with an existing posting list
+  // identified by existing_posting_list_id.
+  //
+  // RETURNS:
+  //   - On success, a valid instance of PostingListIntegerIndexDataAccessor
+  //   - INVALID_ARGUMENT if storage has an invalid block_size.
+  static libtextclassifier3::StatusOr<
+      std::unique_ptr<PostingListIntegerIndexDataAccessor>>
+  CreateFromExisting(FlashIndexStorage* storage,
+                     PostingListUsedIntegerIndexDataSerializer* serializer,
+                     PostingListIdentifier existing_posting_list_id);
+
+  PostingListUsedSerializer* GetSerializer() override { return serializer_; }
+
+  // Retrieve the next batch of data in the posting list chain
+  //
+  // RETURNS:
+  //   - On success, a vector of integer index data in the posting list chain
+  //   - INTERNAL if called on an instance that was created via Create, if
+  //     unable to read the next posting list in the chain or if the posting
+  //     list has been corrupted somehow.
+  libtextclassifier3::StatusOr<std::vector<IntegerIndexData>>
+  GetNextDataBatch();
+
+  // Prepend one data. This may result in flushing the posting list to disk (if
+  // the PostingListIntegerIndexDataAccessor holds a max-sized posting list that
+  // is full) or freeing a pre-existing posting list if it is too small to fit
+  // all data necessary.
+  //
+  // RETURNS:
+  //   - OK, on success
+  //   - INVALID_ARGUMENT if !data.is_valid() or if data is greater than the
+  //     previously added data.
+  //   - RESOURCE_EXHAUSTED error if unable to grow the index to allocate a new
+  //     posting list.
+  libtextclassifier3::Status PrependData(const IntegerIndexData& data);
+
+  // TODO(b/259743562): [Optimization 1] add GetAndClear, IsFull for split
+
+ private:
+  explicit PostingListIntegerIndexDataAccessor(
+      FlashIndexStorage* storage,
+      std::unique_ptr<uint8_t[]> posting_list_buffer_array,
+      PostingListUsed posting_list_buffer,
+      PostingListUsedIntegerIndexDataSerializer* serializer)
+      : PostingListAccessor(storage, std::move(posting_list_buffer_array),
+                            std::move(posting_list_buffer)),
+        serializer_(serializer) {}
+
+  PostingListUsedIntegerIndexDataSerializer* serializer_;  // Does not own.
+};
+
+}  // namespace lib
+}  // namespace icing
+
+#endif  // ICING_INDEX_NUMERIC_POSTING_LIST_INTEGER_INDEX_DATA_ACCESSOR_H_