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diff --git a/runtime/base/stringpiece.h b/runtime/base/stringpiece.h
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--- /dev/null
+++ b/runtime/base/stringpiece.h
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+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * 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.
+ */
+
+// A string-like object that points to a sized piece of memory.
+//
+// Functions or methods may use const StringPiece& parameters to accept either
+// a "const char*" or a "string" value that will be implicitly converted to
+// a StringPiece.  The implicit conversion means that it is often appropriate
+// to include this .h file in other files rather than forward-declaring
+// StringPiece as would be appropriate for most other Google classes.
+//
+// Systematic usage of StringPiece is encouraged as it will reduce unnecessary
+// conversions from "const char*" to "string" and back again.
+
+#ifndef ART_SRC_BASE_STRINGPIECE_H_
+#define ART_SRC_BASE_STRINGPIECE_H_
+
+#include <string.h>
+#include <algorithm>
+#include <cstddef>
+#include <iosfwd>
+#include <string>
+
+namespace art {
+
+class StringPiece {
+ private:
+  const char*   ptr_;
+  int           length_;
+
+ public:
+  // We provide non-explicit singleton constructors so users can pass
+  // in a "const char*" or a "string" wherever a "StringPiece" is
+  // expected.
+  StringPiece() : ptr_(NULL), length_(0) { }
+  StringPiece(const char* str)  // NOLINT
+    : ptr_(str), length_((str == NULL) ? 0 : static_cast<int>(strlen(str))) { }
+  StringPiece(const std::string& str)  // NOLINT
+    : ptr_(str.data()), length_(static_cast<int>(str.size())) { }
+  StringPiece(const char* offset, int len) : ptr_(offset), length_(len) { }
+
+  // data() may return a pointer to a buffer with embedded NULs, and the
+  // returned buffer may or may not be null terminated.  Therefore it is
+  // typically a mistake to pass data() to a routine that expects a NUL
+  // terminated string.
+  const char* data() const { return ptr_; }
+  int size() const { return length_; }
+  int length() const { return length_; }
+  bool empty() const { return length_ == 0; }
+
+  void clear() {
+    ptr_ = NULL;
+    length_ = 0;
+  }
+  void set(const char* data, int len) {
+    ptr_ = data;
+    length_ = len;
+  }
+  void set(const char* str) {
+    ptr_ = str;
+    if (str != NULL)
+      length_ = static_cast<int>(strlen(str));
+    else
+      length_ = 0;
+  }
+  void set(const void* data, int len) {
+    ptr_ = reinterpret_cast<const char*>(data);
+    length_ = len;
+  }
+
+  char operator[](int i) const { return ptr_[i]; }
+
+  void remove_prefix(int n) {
+    ptr_ += n;
+    length_ -= n;
+  }
+
+  void remove_suffix(int n) {
+    length_ -= n;
+  }
+
+  int compare(const StringPiece& x) const;
+
+  std::string as_string() const {
+    return std::string(data(), size());
+  }
+  // We also define ToString() here, since many other string-like
+  // interfaces name the routine that converts to a C++ string
+  // "ToString", and it's confusing to have the method that does that
+  // for a StringPiece be called "as_string()".  We also leave the
+  // "as_string()" method defined here for existing code.
+  std::string ToString() const {
+    return std::string(data(), size());
+  }
+
+  void CopyToString(std::string* target) const;
+  void AppendToString(std::string* target) const;
+
+  // Does "this" start with "x"
+  bool starts_with(const StringPiece& x) const {
+    return ((length_ >= x.length_) &&
+            (memcmp(ptr_, x.ptr_, x.length_) == 0));
+  }
+
+  // Does "this" end with "x"
+  bool ends_with(const StringPiece& x) const {
+    return ((length_ >= x.length_) &&
+            (memcmp(ptr_ + (length_-x.length_), x.ptr_, x.length_) == 0));
+  }
+
+  // standard STL container boilerplate
+  typedef char value_type;
+  typedef const char* pointer;
+  typedef const char& reference;
+  typedef const char& const_reference;
+  typedef size_t size_type;
+  typedef ptrdiff_t difference_type;
+  static const size_type npos;
+  typedef const char* const_iterator;
+  typedef const char* iterator;
+  typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+  typedef std::reverse_iterator<iterator> reverse_iterator;
+  iterator begin() const { return ptr_; }
+  iterator end() const { return ptr_ + length_; }
+  const_reverse_iterator rbegin() const {
+    return const_reverse_iterator(ptr_ + length_);
+  }
+  const_reverse_iterator rend() const {
+    return const_reverse_iterator(ptr_);
+  }
+  // STLS says return size_type, but Google says return int
+  int max_size() const { return length_; }
+  int capacity() const { return length_; }
+
+  int copy(char* buf, size_type n, size_type pos = 0) const;
+
+  size_type find(const StringPiece& s, size_type pos = 0) const;
+  size_type find(char c, size_type pos = 0) const;
+  size_type rfind(const StringPiece& s, size_type pos = npos) const;
+  size_type rfind(char c, size_type pos = npos) const;
+
+  StringPiece substr(size_type pos, size_type n = npos) const;
+};
+
+// This large function is defined inline so that in a fairly common case where
+// one of the arguments is a literal, the compiler can elide a lot of the
+// following comparisons.
+inline bool operator==(const StringPiece& x, const StringPiece& y) {
+  int len = x.size();
+  if (len != y.size()) {
+    return false;
+  }
+
+  const char* p1 = x.data();
+  const char* p2 = y.data();
+  if (p1 == p2) {
+    return true;
+  }
+  if (len <= 0) {
+    return true;
+  }
+
+  // Test last byte in case strings share large common prefix
+  if (p1[len-1] != p2[len-1]) return false;
+  if (len == 1) return true;
+
+  // At this point we can, but don't have to, ignore the last byte.  We use
+  // this observation to fold the odd-length case into the even-length case.
+  len &= ~1;
+
+  return memcmp(p1, p2, len) == 0;
+}
+
+inline bool operator!=(const StringPiece& x, const StringPiece& y) {
+  return !(x == y);
+}
+
+inline bool operator<(const StringPiece& x, const StringPiece& y) {
+  const int r = memcmp(x.data(), y.data(),
+                       std::min(x.size(), y.size()));
+  return ((r < 0) || ((r == 0) && (x.size() < y.size())));
+}
+
+inline bool operator>(const StringPiece& x, const StringPiece& y) {
+  return y < x;
+}
+
+inline bool operator<=(const StringPiece& x, const StringPiece& y) {
+  return !(x > y);
+}
+
+inline bool operator>=(const StringPiece& x, const StringPiece& y) {
+  return !(x < y);
+}
+
+extern std::ostream& operator<<(std::ostream& o, const StringPiece& piece);
+
+struct StringPieceHash {
+  size_t operator()(const StringPiece& string_piece) const {
+    size_t string_size = string_piece.size();
+    const char* string_data = string_piece.data();
+    // This is the java.lang.String hashcode for convenience, not interoperability.
+    size_t hash = 0;
+    while (string_size--) {
+      hash = hash * 31 + *string_data++;
+    }
+    return hash;
+  }
+};
+
+}  // namespace art
+
+#endif  // ART_SRC_BASE_STRINGPIECE_H_