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_WRITER_H_ 6 #define BASE_JSON_JSON_WRITER_H_ 7 8 #include <string> 9 10 #include "base/base_export.h" 11 #include "base/basictypes.h" 12 13 namespace base { 14 15 class Value; 16 17 class BASE_EXPORT JSONWriter { 18 public: 19 enum Options { 20 // This option instructs the writer that if a Binary value is encountered, 21 // the value (and key if within a dictionary) will be omitted from the 22 // output, and success will be returned. Otherwise, if a binary value is 23 // encountered, failure will be returned. 24 OPTIONS_OMIT_BINARY_VALUES = 1 << 0, 25 26 // This option instructs the writer to write doubles that have no fractional 27 // part as a normal integer (i.e., without using exponential notation 28 // or appending a '.0') as long as the value is within the range of a 29 // 64-bit int. 30 OPTIONS_OMIT_DOUBLE_TYPE_PRESERVATION = 1 << 1, 31 32 // Return a slightly nicer formatted json string (pads with whitespace to 33 // help with readability). 34 OPTIONS_PRETTY_PRINT = 1 << 2, 35 }; 36 37 // Given a root node, generates a JSON string and puts it into |json|. 38 // TODO(tc): Should we generate json if it would be invalid json (e.g., 39 // |node| is not a DictionaryValue/ListValue or if there are inf/-inf float 40 // values)? Return true on success and false on failure. 41 static bool Write(const Value* const node, std::string* json); 42 43 // Same as above but with |options| which is a bunch of JSONWriter::Options 44 // bitwise ORed together. Return true on success and false on failure. 45 static bool WriteWithOptions(const Value* const node, int options, 46 std::string* json); 47 48 private: 49 JSONWriter(int options, std::string* json); 50 51 // Called recursively to build the JSON string. When completed, 52 // |json_string_| will contain the JSON. 53 bool BuildJSONString(const Value* const node, size_t depth); 54 55 // Adds space to json_string_ for the indent level. 56 void IndentLine(size_t depth); 57 58 bool omit_binary_values_; 59 bool omit_double_type_preservation_; 60 bool pretty_print_; 61 62 // Where we write JSON data as we generate it. 63 std::string* json_string_; 64 65 DISALLOW_COPY_AND_ASSIGN(JSONWriter); 66 }; 67 68 } // namespace base 69 70 #endif // BASE_JSON_JSON_WRITER_H_ 71
