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diff --git a/src/binary_parse/cached_paged_byte_array.h b/src/binary_parse/cached_paged_byte_array.h
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+// Copyright 2015 Google Inc.
+//
+// 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.
+//
+////////////////////////////////////////////////////////////////////////////////
+//
+// LRU cache decorator for binary_parse::PagedByteArray subclasses.
+
+#ifndef PIEX_BINARY_PARSE_CACHED_PAGED_BYTE_ARRAY_H_
+#define PIEX_BINARY_PARSE_CACHED_PAGED_BYTE_ARRAY_H_
+
+#include <mutex>
+#include <vector>
+
+#if !defined(WIN32_LEAN_AND_MEAN)
+#define WIN32_LEAN_AND_MEAN
+#endif
+#include "src/binary_parse/range_checked_byte_ptr.h"
+
+namespace piex {
+namespace binary_parse {
+
+class CachedPagedByteArray : public PagedByteArray {
+ public:
+  // Decorates 'paged_byte_array' with a LRU cache layer of the size
+  // 'cache_size'.
+  explicit CachedPagedByteArray(const PagedByteArray* paged_byte_array,
+                                size_t cache_size);
+
+  virtual size_t length() const { return paged_byte_array_->length(); }
+
+  virtual size_t pageSize() const { return paged_byte_array_->pageSize(); }
+
+  virtual void getPage(size_t page_index, const unsigned char** begin,
+                       const unsigned char** end,
+                       PagedByteArray::PagePtr* page) const;
+
+ private:
+  struct CachedPage {
+    size_t index;
+    PagedByteArray::PagePtr page;
+    const unsigned char* begin;
+    const unsigned char* end;
+  };
+
+  // Disallow copy construction and assignment.
+  CachedPagedByteArray(const CachedPagedByteArray&);
+  void operator=(const CachedPagedByteArray&);
+
+  // Gets the index of the page if it is in the cache and returns true, else
+  // returns false.
+  bool getFromCache(size_t page_index, size_t* cache_index) const;
+
+  mutable std::mutex mutex_;
+  const PagedByteArray* paged_byte_array_;
+  const size_t cache_size_;
+  mutable std::vector<CachedPage> cached_pages_;
+};
+
+}  // namespace binary_parse
+}  // namespace piex
+
+#endif  // PIEX_BINARY_PARSE_CACHED_PAGED_BYTE_ARRAY_H_