base/json/json_string_value_serializer.h

   1 // Copyright (c) 2012 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 #ifndef BASE_JSON_JSON_STRING_VALUE_SERIALIZER_H_
   6 #define BASE_JSON_JSON_STRING_VALUE_SERIALIZER_H_
   7
   8 #include <string>
   9
  10 #include "base/base_export.h"
  11 #include "base/basictypes.h"
  12 #include "base/files/file_path.h"
  13 #include "base/values.h"
  14
  15 class BASE_EXPORT JSONStringValueSerializer : public base::ValueSerializer {
  16  public:
  17   // json_string is the string that will be source of the deserialization
  18   // or the destination of the serialization.  The caller of the constructor
  19   // retains ownership of the string.
  20   explicit JSONStringValueSerializer(std::string* json_string)
  21       : json_string_(json_string),
  22         initialized_with_const_string_(false),
  23         pretty_print_(false),
  24         allow_trailing_comma_(false) {
  25   }
  26
  27   // This version allows initialization with a const string reference for
  28   // deserialization only.
  29   explicit JSONStringValueSerializer(const std::string& json_string)
  30       : json_string_(&const_cast<std::string&>(json_string)),
  31         initialized_with_const_string_(true),
  32         pretty_print_(false),
  33         allow_trailing_comma_(false) {
  34   }
  35
  36   virtual ~JSONStringValueSerializer();
  37
  38   // Attempt to serialize the data structure represented by Value into
  39   // JSON.  If the return value is true, the result will have been written
  40   // into the string passed into the constructor.
  41   virtual bool Serialize(const base::Value& root) OVERRIDE;
  42
  43   // Equivalent to Serialize(root) except binary values are omitted from the
  44   // output.
  45   bool SerializeAndOmitBinaryValues(const base::Value& root);
  46
  47   // Attempt to deserialize the data structure encoded in the string passed
  48   // in to the constructor into a structure of Value objects.  If the return
  49   // value is NULL, and if |error_code| is non-null, |error_code| will
  50   // contain an integer error code (a JsonParseError in this case).
  51   // If |error_message| is non-null, it will be filled in with a formatted
  52   // error message including the location of the error if appropriate.
  53   // The caller takes ownership of the returned value.
  54   virtual base::Value* Deserialize(int* error_code,
  55                                    std::string* error_message) OVERRIDE;
  56
  57   void set_pretty_print(bool new_value) { pretty_print_ = new_value; }
  58   bool pretty_print() { return pretty_print_; }
  59
  60   void set_allow_trailing_comma(bool new_value) {
  61     allow_trailing_comma_ = new_value;
  62   }
  63
  64  private:
  65   bool SerializeInternal(const base::Value& root, bool omit_binary_values);
  66
  67   std::string* json_string_;
  68   bool initialized_with_const_string_;
  69   bool pretty_print_;  // If true, serialization will span multiple lines.
  70   // If true, deserialization will allow trailing commas.
  71   bool allow_trailing_comma_;
  72
  73   DISALLOW_COPY_AND_ASSIGN(JSONStringValueSerializer);
  74 };
  75
  76 #endif  // BASE_JSON_JSON_STRING_VALUE_SERIALIZER_H_
  77