1 // Protocol Buffers - Google's data interchange format 2 // Copyright 2008 Google Inc. All rights reserved. 3 // https://developers.google.com/protocol-buffers/ 4 // 5 // Redistribution and use in source and binary forms, with or without 6 // modification, are permitted provided that the following conditions are 7 // met: 8 // 9 // * Redistributions of source code must retain the above copyright 10 // notice, this list of conditions and the following disclaimer. 11 // * Redistributions in binary form must reproduce the above 12 // copyright notice, this list of conditions and the following disclaimer 13 // in the documentation and/or other materials provided with the 14 // distribution. 15 // * Neither the name of Google Inc. nor the names of its 16 // contributors may be used to endorse or promote products derived from 17 // this software without specific prior written permission. 18 // 19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 22 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 23 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 24 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 25 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 29 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 31 #ifndef GOOGLE_PROTOBUF_UTIL_CONVERTER_OBJECT_WRITER_H__ 32 #define GOOGLE_PROTOBUF_UTIL_CONVERTER_OBJECT_WRITER_H__ 33 34 #include <google/protobuf/stubs/common.h> 35 #include <google/protobuf/stubs/strutil.h> 36 37 // Must be included last. 38 #include <google/protobuf/port_def.inc> 39 40 namespace google { 41 namespace protobuf { 42 namespace util { 43 namespace converter { 44 45 46 class DataPiece; 47 48 // An ObjectWriter is an interface for writing a stream of events 49 // representing objects and collections. Implementation of this 50 // interface can be used to write an object stream to an in-memory 51 // structure, protobufs, JSON, XML, or any other output format 52 // desired. The ObjectSource interface is typically used as the 53 // source of an object stream. 54 // 55 // See JsonObjectWriter for a sample implementation of ObjectWriter 56 // and its use. 57 // 58 // Derived classes could be thread-unsafe. 59 // 60 // TODO(xinb): seems like a prime candidate to apply the RAII paradigm 61 // and get rid the need to call EndXXX(). 62 class PROTOBUF_EXPORT ObjectWriter { 63 public: ~ObjectWriter()64 virtual ~ObjectWriter() {} 65 66 // Starts an object. If the name is empty, the object will not be named. 67 virtual ObjectWriter* StartObject(StringPiece name) = 0; 68 69 // Ends an object. 70 virtual ObjectWriter* EndObject() = 0; 71 72 // Starts a list. If the name is empty, the list will not be named. 73 virtual ObjectWriter* StartList(StringPiece name) = 0; 74 75 // Ends a list. 76 virtual ObjectWriter* EndList() = 0; 77 78 // Renders a boolean value. 79 virtual ObjectWriter* RenderBool(StringPiece name, bool value) = 0; 80 81 // Renders an 32-bit integer value. 82 virtual ObjectWriter* RenderInt32(StringPiece name, int32 value) = 0; 83 84 // Renders an 32-bit unsigned integer value. 85 virtual ObjectWriter* RenderUint32(StringPiece name, uint32 value) = 0; 86 87 // Renders a 64-bit integer value. 88 virtual ObjectWriter* RenderInt64(StringPiece name, int64 value) = 0; 89 90 // Renders an 64-bit unsigned integer value. 91 virtual ObjectWriter* RenderUint64(StringPiece name, uint64 value) = 0; 92 93 94 // Renders a double value. 95 virtual ObjectWriter* RenderDouble(StringPiece name, double value) = 0; 96 // Renders a float value. 97 virtual ObjectWriter* RenderFloat(StringPiece name, float value) = 0; 98 99 // Renders a StringPiece value. This is for rendering strings. 100 virtual ObjectWriter* RenderString(StringPiece name, 101 StringPiece value) = 0; 102 103 // Renders a bytes value. 104 virtual ObjectWriter* RenderBytes(StringPiece name, StringPiece value) = 0; 105 106 // Renders a Null value. 107 virtual ObjectWriter* RenderNull(StringPiece name) = 0; 108 109 110 // Renders a DataPiece object to a ObjectWriter. 111 static void RenderDataPieceTo(const DataPiece& data, StringPiece name, 112 ObjectWriter* ow); 113 114 115 // Indicates whether this ObjectWriter has completed writing the root message, 116 // usually this means writing of one complete object. Subclasses must override 117 // this behavior appropriately. done()118 virtual bool done() { return false; } 119 set_use_strict_base64_decoding(bool value)120 void set_use_strict_base64_decoding(bool value) { 121 use_strict_base64_decoding_ = value; 122 } 123 use_strict_base64_decoding()124 bool use_strict_base64_decoding() const { 125 return use_strict_base64_decoding_; 126 } 127 128 protected: ObjectWriter()129 ObjectWriter() : use_strict_base64_decoding_(true) {} 130 131 private: 132 // If set to true, we use the stricter version of base64 decoding for byte 133 // fields by making sure decoded version encodes back to the original string. 134 bool use_strict_base64_decoding_; 135 136 // Do not add any data members to this class. 137 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ObjectWriter); 138 }; 139 140 } // namespace converter 141 } // namespace util 142 } // namespace protobuf 143 } // namespace google 144 145 #include <google/protobuf/port_undef.inc> 146 147 #endif // GOOGLE_PROTOBUF_UTIL_CONVERTER_OBJECT_WRITER_H__ 148