prettywriter.h
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3 // Copyright (C) 2015 THL A29 Limited, a Tencent company, and Milo Yip. All rights reserved.
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14 
15 #ifndef RAPIDJSON_PRETTYWRITER_H_
16 #define RAPIDJSON_PRETTYWRITER_H_
17 
18 #include "writer.h"
19 
20 #ifdef __GNUC__
21 RAPIDJSON_DIAG_PUSH
22 RAPIDJSON_DIAG_OFF(effc++)
23 #endif
24 
25 #if defined(__clang__)
26 RAPIDJSON_DIAG_PUSH
27 RAPIDJSON_DIAG_OFF(c++98-compat)
28 #endif
29 
30 RAPIDJSON_NAMESPACE_BEGIN
31 
32 //! Combination of PrettyWriter format flags.
33 /*! \see PrettyWriter::SetFormatOptions
34  */
36  kFormatDefault = 0, //!< Default pretty formatting.
37  kFormatSingleLineArray = 1 //!< Format arrays on a single line.
38 };
39 
40 //! Writer with indentation and spacing.
41 /*!
42  \tparam OutputStream Type of output os.
43  \tparam SourceEncoding Encoding of source string.
44  \tparam TargetEncoding Encoding of output stream.
45  \tparam StackAllocator Type of allocator for allocating memory of stack.
46 */
47 template<typename OutputStream, typename SourceEncoding = UTF8<>, typename TargetEncoding = UTF8<>, typename StackAllocator = CrtAllocator, unsigned writeFlags = kWriteDefaultFlags>
48 class PrettyWriter : public Writer<OutputStream, SourceEncoding, TargetEncoding, StackAllocator, writeFlags> {
49 public:
51  typedef typename Base::Ch Ch;
52 
53  //! Constructor
54  /*! \param os Output stream.
55  \param allocator User supplied allocator. If it is null, it will create a private one.
56  \param levelDepth Initial capacity of stack.
57  */
58  explicit PrettyWriter(OutputStream& os, StackAllocator* allocator = 0, size_t levelDepth = Base::kDefaultLevelDepth) :
59  Base(os, allocator, levelDepth), indentChar_(' '), indentCharCount_(4), formatOptions_(kFormatDefault) {}
60 
61 
62  explicit PrettyWriter(StackAllocator* allocator = 0, size_t levelDepth = Base::kDefaultLevelDepth) :
63  Base(allocator, levelDepth), indentChar_(' '), indentCharCount_(4) {}
64 
65 #if RAPIDJSON_HAS_CXX11_RVALUE_REFS
66  PrettyWriter(PrettyWriter&& rhs) :
67  Base(std::forward<PrettyWriter>(rhs)), indentChar_(rhs.indentChar_), indentCharCount_(rhs.indentCharCount_), formatOptions_(rhs.formatOptions_) {}
68 #endif
69 
70  //! Set custom indentation.
71  /*! \param indentChar Character for indentation. Must be whitespace character (' ', '\\t', '\\n', '\\r').
72  \param indentCharCount Number of indent characters for each indentation level.
73  \note The default indentation is 4 spaces.
74  */
75  PrettyWriter& SetIndent(Ch indentChar, unsigned indentCharCount) {
76  RAPIDJSON_ASSERT(indentChar == ' ' || indentChar == '\t' || indentChar == '\n' || indentChar == '\r');
77  indentChar_ = indentChar;
78  indentCharCount_ = indentCharCount;
79  return *this;
80  }
81 
82  //! Set pretty writer formatting options.
83  /*! \param options Formatting options.
84  */
86  formatOptions_ = options;
87  return *this;
88  }
89 
90  /*! @name Implementation of Handler
91  \see Handler
92  */
93  //@{
94 
95  bool Null() { PrettyPrefix(kNullType); return Base::WriteNull(); }
96  bool Bool(bool b) { PrettyPrefix(b ? kTrueType : kFalseType); return Base::WriteBool(b); }
97  bool Int(int i) { PrettyPrefix(kNumberType); return Base::WriteInt(i); }
98  bool Uint(unsigned u) { PrettyPrefix(kNumberType); return Base::WriteUint(u); }
99  bool Int64(int64_t i64) { PrettyPrefix(kNumberType); return Base::WriteInt64(i64); }
100  bool Uint64(uint64_t u64) { PrettyPrefix(kNumberType); return Base::WriteUint64(u64); }
101  bool Double(double d) { PrettyPrefix(kNumberType); return Base::WriteDouble(d); }
102 
103  bool RawNumber(const Ch* str, SizeType length, bool copy = false) {
104  RAPIDJSON_ASSERT(str != 0);
105  (void)copy;
106  PrettyPrefix(kNumberType);
107  return Base::WriteString(str, length);
108  }
109 
110  bool String(const Ch* str, SizeType length, bool copy = false) {
111  RAPIDJSON_ASSERT(str != 0);
112  (void)copy;
113  PrettyPrefix(kStringType);
114  return Base::WriteString(str, length);
115  }
116 
117 #if RAPIDJSON_HAS_STDSTRING
118  bool String(const std::basic_string<Ch>& str) {
119  return String(str.data(), SizeType(str.size()));
120  }
121 #endif
122 
123  bool StartObject() {
124  PrettyPrefix(kObjectType);
125  new (Base::level_stack_.template Push<typename Base::Level>()) typename Base::Level(false);
126  return Base::WriteStartObject();
127  }
128 
129  bool Key(const Ch* str, SizeType length, bool copy = false) { return String(str, length, copy); }
130 
131 #if RAPIDJSON_HAS_STDSTRING
132  bool Key(const std::basic_string<Ch>& str) {
133  return Key(str.data(), SizeType(str.size()));
134  }
135 #endif
136 
137  bool EndObject(SizeType memberCount = 0) {
138  (void)memberCount;
139  RAPIDJSON_ASSERT(Base::level_stack_.GetSize() >= sizeof(typename Base::Level)); // not inside an Object
140  RAPIDJSON_ASSERT(!Base::level_stack_.template Top<typename Base::Level>()->inArray); // currently inside an Array, not Object
141  RAPIDJSON_ASSERT(0 == Base::level_stack_.template Top<typename Base::Level>()->valueCount % 2); // Object has a Key without a Value
142 
143  bool empty = Base::level_stack_.template Pop<typename Base::Level>(1)->valueCount == 0;
144 
145  if (!empty) {
146  Base::os_->Put('\n');
147  WriteIndent();
148  }
149  bool ret = Base::WriteEndObject();
150  (void)ret;
151  RAPIDJSON_ASSERT(ret == true);
152  if (Base::level_stack_.Empty()) // end of json text
153  Base::Flush();
154  return true;
155  }
156 
157  bool StartArray() {
158  PrettyPrefix(kArrayType);
159  new (Base::level_stack_.template Push<typename Base::Level>()) typename Base::Level(true);
160  return Base::WriteStartArray();
161  }
162 
163  bool EndArray(SizeType memberCount = 0) {
164  (void)memberCount;
165  RAPIDJSON_ASSERT(Base::level_stack_.GetSize() >= sizeof(typename Base::Level));
166  RAPIDJSON_ASSERT(Base::level_stack_.template Top<typename Base::Level>()->inArray);
167  bool empty = Base::level_stack_.template Pop<typename Base::Level>(1)->valueCount == 0;
168 
169  if (!empty && !(formatOptions_ & kFormatSingleLineArray)) {
170  Base::os_->Put('\n');
171  WriteIndent();
172  }
173  bool ret = Base::WriteEndArray();
174  (void)ret;
175  RAPIDJSON_ASSERT(ret == true);
176  if (Base::level_stack_.Empty()) // end of json text
177  Base::Flush();
178  return true;
179  }
180 
181  //@}
182 
183  /*! @name Convenience extensions */
184  //@{
185 
186  //! Simpler but slower overload.
187  bool String(const Ch* str) { return String(str, internal::StrLen(str)); }
188  bool Key(const Ch* str) { return Key(str, internal::StrLen(str)); }
189 
190  //@}
191 
192  //! Write a raw JSON value.
193  /*!
194  For user to write a stringified JSON as a value.
195 
196  \param json A well-formed JSON value. It should not contain null character within [0, length - 1] range.
197  \param length Length of the json.
198  \param type Type of the root of json.
199  \note When using PrettyWriter::RawValue(), the result json may not be indented correctly.
200  */
201  bool RawValue(const Ch* json, size_t length, Type type) {
202  RAPIDJSON_ASSERT(json != 0);
203  PrettyPrefix(type);
204  return Base::WriteRawValue(json, length);
205  }
206 
207 protected:
208  void PrettyPrefix(Type type) {
209  (void)type;
210  if (Base::level_stack_.GetSize() != 0) { // this value is not at root
211  typename Base::Level* level = Base::level_stack_.template Top<typename Base::Level>();
212 
213  if (level->inArray) {
214  if (level->valueCount > 0) {
215  Base::os_->Put(','); // add comma if it is not the first element in array
216  if (formatOptions_ & kFormatSingleLineArray)
217  Base::os_->Put(' ');
218  }
219 
220  if (!(formatOptions_ & kFormatSingleLineArray)) {
221  Base::os_->Put('\n');
222  WriteIndent();
223  }
224  }
225  else { // in object
226  if (level->valueCount > 0) {
227  if (level->valueCount % 2 == 0) {
228  Base::os_->Put(',');
229  Base::os_->Put('\n');
230  }
231  else {
232  Base::os_->Put(':');
233  Base::os_->Put(' ');
234  }
235  }
236  else
237  Base::os_->Put('\n');
238 
239  if (level->valueCount % 2 == 0)
240  WriteIndent();
241  }
242  if (!level->inArray && level->valueCount % 2 == 0)
243  RAPIDJSON_ASSERT(type == kStringType); // if it's in object, then even number should be a name
244  level->valueCount++;
245  }
246  else {
247  RAPIDJSON_ASSERT(!Base::hasRoot_); // Should only has one and only one root.
248  Base::hasRoot_ = true;
249  }
250  }
251 
252  void WriteIndent() {
253  size_t count = (Base::level_stack_.GetSize() / sizeof(typename Base::Level)) * indentCharCount_;
254  PutN(*Base::os_, static_cast<typename OutputStream::Ch>(indentChar_), count);
255  }
256 
257  Ch indentChar_;
258  unsigned indentCharCount_;
259  PrettyFormatOptions formatOptions_;
260 
261 private:
262  // Prohibit copy constructor & assignment operator.
263  PrettyWriter(const PrettyWriter&);
264  PrettyWriter& operator=(const PrettyWriter&);
265 };
266 
267 RAPIDJSON_NAMESPACE_END
268 
269 #if defined(__clang__)
270 RAPIDJSON_DIAG_POP
271 #endif
272 
273 #ifdef __GNUC__
274 RAPIDJSON_DIAG_POP
275 #endif
276 
277 #endif // RAPIDJSON_RAPIDJSON_H_
true
Definition: rapidjson.h:623
bool inArray
true if in array, otherwise in object
Definition: writer.h:290
bool String(const Ch *str)
Simpler but slower overload.
Definition: prettywriter.h:187
PrettyFormatOptions
Combination of PrettyWriter format flags.
Definition: prettywriter.h:35
Format arrays on a single line.
Definition: prettywriter.h:37
unsigned SizeType
Size type (for string lengths, array sizes, etc.)
Definition: rapidjson.h:389
false
Definition: rapidjson.h:622
Writer with indentation and spacing.
Definition: fwd.h:100
Information for each nested level.
Definition: writer.h:287
size_t valueCount
number of values in this level
Definition: writer.h:289
bool RawValue(const Ch *json, size_t length, Type type)
Write a raw JSON value.
Definition: prettywriter.h:201
Type
Type of JSON value.
Definition: rapidjson.h:620
object
Definition: rapidjson.h:624
array
Definition: rapidjson.h:625
void PutN(FileWriteStream &stream, char c, size_t n)
Implement specialized version of PutN() with memset() for better performance.
Definition: filewritestream.h:94
JSON writer.
Definition: fwd.h:95
null
Definition: rapidjson.h:621
Default pretty formatting.
Definition: prettywriter.h:36
string
Definition: rapidjson.h:626
PrettyWriter & SetIndent(Ch indentChar, unsigned indentCharCount)
Set custom indentation.
Definition: prettywriter.h:75
PrettyWriter(OutputStream &os, StackAllocator *allocator=0, size_t levelDepth=Base::kDefaultLevelDepth)
Constructor.
Definition: prettywriter.h:58
PrettyWriter & SetFormatOptions(PrettyFormatOptions options)
Set pretty writer formatting options.
Definition: prettywriter.h:85
#define RAPIDJSON_ASSERT(x)
Assertion.
Definition: rapidjson.h:411
number
Definition: rapidjson.h:627