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diff --git a/icing/index/property-existence-indexing-handler.h b/icing/index/property-existence-indexing-handler.h
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+// Copyright (C) 2023 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_PROPERTY_EXISTENCE_INDEXING_HANDLER_H_
+#define ICING_INDEX_PROPERTY_EXISTENCE_INDEXING_HANDLER_H_
+
+#include <memory>
+#include <string_view>
+
+#include "icing/text_classifier/lib3/utils/base/status.h"
+#include "icing/text_classifier/lib3/utils/base/statusor.h"
+#include "icing/index/index.h"
+#include "icing/proto/logging.pb.h"
+#include "icing/store/document-id.h"
+#include "icing/util/clock.h"
+#include "icing/util/tokenized-document.h"
+
+namespace icing {
+namespace lib {
+
+inline constexpr std::string_view kPropertyExistenceTokenPrefix =
+    "\xFF_HAS_\xFF";
+
+// This class is meant to be owned by TermIndexingHandler. Instead of using this
+// handler directly, callers should use TermIndexingHandler to index documents.
+//
+// This handler will not check or set last_added_document_id of the index, and
+// it will not merge or sort the lite index either.
+class PropertyExistenceIndexingHandler {
+ public:
+  // Creates a PropertyExistenceIndexingHandler instance which does not take
+  // ownership of any input components. All pointers must refer to valid objects
+  // that outlive the created PropertyExistenceIndexingHandler instance.
+  //
+  // Returns:
+  //   - A PropertyExistenceIndexingHandler instance on success
+  //   - FAILED_PRECONDITION_ERROR if any of the input pointer is null
+  static libtextclassifier3::StatusOr<
+      std::unique_ptr<PropertyExistenceIndexingHandler>>
+  Create(const Clock* clock, Index* index);
+
+  ~PropertyExistenceIndexingHandler() = default;
+
+  // Handles the property existence indexing process: add hits for metadata
+  // tokens used to index property existence.
+  //
+  // For example, if the passed in document has string properties "propA",
+  // "propB" and "propC.propD", and document property "propC", this handler will
+  // add the following metadata token to the index.
+  // - kPropertyExistenceTokenPrefix + "propA"
+  // - kPropertyExistenceTokenPrefix + "propB"
+  // - kPropertyExistenceTokenPrefix + "propC"
+  // - kPropertyExistenceTokenPrefix + "propC.propD"
+  //
+  /// Returns:
+  //   - OK on success
+  //   - RESOURCE_EXHAUSTED_ERROR if the index is full and can't add anymore
+  //     content.
+  //   - INTERNAL_ERROR if any other errors occur.
+  libtextclassifier3::Status Handle(const TokenizedDocument& tokenized_document,
+                                    DocumentId document_id,
+                                    PutDocumentStatsProto* put_document_stats);
+
+ private:
+  explicit PropertyExistenceIndexingHandler(const Clock& clock, Index* index)
+      : clock_(clock), index_(*index) {}
+
+  const Clock& clock_;  // Does not own.
+  Index& index_;        // Does not own.
+};
+
+}  // namespace lib
+}  // namespace icing
+
+#endif  // ICING_INDEX_PROPERTY_EXISTENCE_INDEXING_HANDLER_H_