third_party/libaddressinput/chromium/string_compare.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "third_party/libaddressinput/src/cpp/src/util/string_compare.h"
   6
   7 #include "base/basictypes.h"
   8 #include "base/lazy_instance.h"
   9 #include "base/logging.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "third_party/icu/source/i18n/unicode/coll.h"
  12
  13 namespace i18n {
  14 namespace addressinput {
  15
  16 namespace {
  17
  18 class IcuStringComparer {
  19  public:
  20   IcuStringComparer() {
  21     UErrorCode error_code = U_ZERO_ERROR;
  22     collator_.reset(
  23         icu::Collator::createInstance(icu::Locale::getRoot(), error_code));
  24     DCHECK(U_SUCCESS(error_code));
  25     collator_->setStrength(icu::Collator::PRIMARY);
  26   }
  27
  28   ~IcuStringComparer() {}
  29
  30   int Compare(const std::string& a, const std::string& b) const {
  31     UErrorCode error_code = U_ZERO_ERROR;
  32     int result = collator_->compareUTF8(a, b, error_code);
  33     DCHECK(U_SUCCESS(error_code));
  34     return result;
  35   }
  36
  37  private:
  38   // ::scoped_ptr is from "base/memory/scoped_ptr.h", which does not interfere
  39   // with ::i18n::addressinput::scoped_ptr from
  40   // <libaddressinput/util/scoped_ptr.h>.
  41   ::scoped_ptr<icu::Collator> collator_;
  42
  43   DISALLOW_COPY_AND_ASSIGN(IcuStringComparer);
  44 };
  45
  46 static base::LazyInstance<IcuStringComparer> g_comparer =
  47     LAZY_INSTANCE_INITIALIZER;
  48
  49 }  // namespace
  50
  51 // Dummy required for scoped_ptr<Impl>.
  52 class StringCompare::Impl {};
  53
  54 StringCompare::StringCompare() {}
  55
  56 StringCompare::~StringCompare() {}
  57
  58 bool StringCompare::NaturalEquals(const std::string& a,
  59                                   const std::string& b) const {
  60   return g_comparer.Get().Compare(a, b) == 0;
  61 }
  62
  63 bool StringCompare::NaturalLess(const std::string& a,
  64                                 const std::string& b) const {
  65   return g_comparer.Get().Compare(a, b) < 0;
  66 }
  67
  68 }  // namespace addressinput
  69 }  // namespace i18n