diff --git a/include/json/writer.h b/include/json/writer.h index cf0eb0c..cfa92c6 100644 --- a/include/json/writer.h +++ b/include/json/writer.h @@ -30,6 +30,7 @@ namespace Json { { public: FastWriter(); + virtual ~FastWriter(){} void enableYAMLCompatibility(); @@ -61,7 +62,7 @@ namespace Json { * * \sa Reader, Value, Value::setComment() */ - class JSON_API StyledWriter + class JSON_API StyledWriter: public Writer { public: StyledWriter(); @@ -98,13 +99,71 @@ namespace Json { bool addChildValues_; }; + /** \brief Writes a Value in JSON format in a human friendly way, + to a stream rather than to a string. + * + * The rules for line break and indent are as follow: + * - Object value: + * - if empty then print {} without indent and line break + * - if not empty the print '{', line break & indent, print one value per line + * and then unindent and line break and print '}'. + * - Array value: + * - if empty then print [] without indent and line break + * - if the array contains no object value, empty array or some other value types, + * and all the values fit on one lines, then print the array on a single line. + * - otherwise, it the values do not fit on one line, or the array contains + * object or non empty array, then print one value per line. + * + * If the Value have comments then they are outputed according to their #CommentPlacement. + * + * \param indentation Each level will be indented by this amount extra. + * \sa Reader, Value, Value::setComment() + */ + class JSON_API StyledStreamWriter + { + public: + StyledStreamWriter( std::string indentation="\t" ); + ~StyledStreamWriter(){} + + public: + /** \brief Serialize a Value in JSON format. + * \param out Stream to write to. (Can be ostringstream, e.g.) + * \param root Value to serialize. + * \note There is no point in deriving from Writer, since write() should not return a value. + */ + void write( std::ostream &out, const Value &root ); + + private: + void writeValue( const Value &value ); + void writeArrayValue( const Value &value ); + bool isMultineArray( const Value &value ); + void pushValue( const std::string &value ); + void writeIndent(); + void writeWithIndent( const std::string &value ); + void indent(); + void unindent(); + void writeCommentBeforeValue( const Value &root ); + void writeCommentAfterValueOnSameLine( const Value &root ); + bool hasCommentForValue( const Value &value ); + static std::string normalizeEOL( const std::string &text ); + + typedef std::vector ChildValues; + + ChildValues childValues_; + std::ostream* document_; + std::string indentString_; + int rightMargin_; + std::string indentation_; + bool addChildValues_; + }; + std::string JSON_API valueToString( Value::Int value ); std::string JSON_API valueToString( Value::UInt value ); std::string JSON_API valueToString( double value ); std::string JSON_API valueToString( bool value ); std::string JSON_API valueToQuotedString( const char *value ); - /// \brief Output using the StyledWriter. + /// \brief Output using the StyledStreamWriter. /// \see Json::operator>>() std::ostream& operator<<( std::ostream&, const Value &root ); diff --git a/src/lib_json/json_writer.cpp b/src/lib_json/json_writer.cpp index c6b8738..b770c1e 100644 --- a/src/lib_json/json_writer.cpp +++ b/src/lib_json/json_writer.cpp @@ -476,10 +476,291 @@ StyledWriter::normalizeEOL( const std::string &text ) return normalized; } + +// Class StyledStreamWriter +// ////////////////////////////////////////////////////////////////// + +StyledStreamWriter::StyledStreamWriter( std::string indentation ) + : document_(NULL) + , rightMargin_( 74 ) + , indentation_( indentation ) +{ +} + + +void +StyledStreamWriter::write( std::ostream &out, const Value &root ) +{ + document_ = &out; + addChildValues_ = false; + indentString_ = ""; + writeCommentBeforeValue( root ); + writeValue( root ); + writeCommentAfterValueOnSameLine( root ); + *document_ << "\n"; + document_ = NULL; // Forget the stream, for safety. +} + + +void +StyledStreamWriter::writeValue( const Value &value ) +{ + switch ( value.type() ) + { + case nullValue: + pushValue( "null" ); + break; + case intValue: + pushValue( valueToString( value.asInt() ) ); + break; + case uintValue: + pushValue( valueToString( value.asUInt() ) ); + break; + case realValue: + pushValue( valueToString( value.asDouble() ) ); + break; + case stringValue: + pushValue( valueToQuotedString( value.asCString() ) ); + break; + case booleanValue: + pushValue( valueToString( value.asBool() ) ); + break; + case arrayValue: + writeArrayValue( value); + break; + case objectValue: + { + Value::Members members( value.getMemberNames() ); + if ( members.empty() ) + pushValue( "{}" ); + else + { + writeWithIndent( "{" ); + indent(); + Value::Members::iterator it = members.begin(); + while ( true ) + { + const std::string &name = *it; + const Value &childValue = value[name]; + writeCommentBeforeValue( childValue ); + writeWithIndent( valueToQuotedString( name.c_str() ) ); + *document_ << " : "; + writeValue( childValue ); + if ( ++it == members.end() ) + { + writeCommentAfterValueOnSameLine( childValue ); + break; + } + *document_ << ","; + writeCommentAfterValueOnSameLine( childValue ); + } + unindent(); + writeWithIndent( "}" ); + } + } + break; + } +} + + +void +StyledStreamWriter::writeArrayValue( const Value &value ) +{ + unsigned size = value.size(); + if ( size == 0 ) + pushValue( "[]" ); + else + { + bool isArrayMultiLine = isMultineArray( value ); + if ( isArrayMultiLine ) + { + writeWithIndent( "[" ); + indent(); + bool hasChildValue = !childValues_.empty(); + unsigned index =0; + while ( true ) + { + const Value &childValue = value[index]; + writeCommentBeforeValue( childValue ); + if ( hasChildValue ) + writeWithIndent( childValues_[index] ); + else + { + writeIndent(); + writeValue( childValue ); + } + if ( ++index == size ) + { + writeCommentAfterValueOnSameLine( childValue ); + break; + } + *document_ << ","; + writeCommentAfterValueOnSameLine( childValue ); + } + unindent(); + writeWithIndent( "]" ); + } + else // output on a single line + { + assert( childValues_.size() == size ); + *document_ << "[ "; + for ( unsigned index =0; index < size; ++index ) + { + if ( index > 0 ) + *document_ << ", "; + *document_ << childValues_[index]; + } + *document_ << " ]"; + } + } +} + + +bool +StyledStreamWriter::isMultineArray( const Value &value ) +{ + int size = value.size(); + bool isMultiLine = size*3 >= rightMargin_ ; + childValues_.clear(); + for ( int index =0; index < size && !isMultiLine; ++index ) + { + const Value &childValue = value[index]; + isMultiLine = isMultiLine || + ( (childValue.isArray() || childValue.isObject()) && + childValue.size() > 0 ); + } + if ( !isMultiLine ) // check if line length > max line length + { + childValues_.reserve( size ); + addChildValues_ = true; + int lineLength = 4 + (size-1)*2; // '[ ' + ', '*n + ' ]' + for ( int index =0; index < size && !isMultiLine; ++index ) + { + writeValue( value[index] ); + lineLength += int( childValues_[index].length() ); + isMultiLine = isMultiLine && hasCommentForValue( value[index] ); + } + addChildValues_ = false; + isMultiLine = isMultiLine || lineLength >= rightMargin_; + } + return isMultiLine; +} + + +void +StyledStreamWriter::pushValue( const std::string &value ) +{ + if ( addChildValues_ ) + childValues_.push_back( value ); + else + *document_ << value; +} + + +void +StyledStreamWriter::writeIndent() +{ + /* + Some comments in this method would have been nice. ;-) + + if ( !document_.empty() ) + { + char last = document_[document_.length()-1]; + if ( last == ' ' ) // already indented + return; + if ( last != '\n' ) // Comments may add new-line + *document_ << '\n'; + } + */ + *document_ << indentString_; +} + + +void +StyledStreamWriter::writeWithIndent( const std::string &value ) +{ + writeIndent(); + *document_ << value; +} + + +void +StyledStreamWriter::indent() +{ + indentString_ += indentation_; +} + + +void +StyledStreamWriter::unindent() +{ + assert( indentString_.size() >= indentation_.size() ); + indentString_.resize( indentString_.size() - indentation_.size() ); +} + + +void +StyledStreamWriter::writeCommentBeforeValue( const Value &root ) +{ + if ( !root.hasComment( commentBefore ) ) + return; + *document_ << normalizeEOL( root.getComment( commentBefore ) ); + *document_ << "\n"; +} + + +void +StyledStreamWriter::writeCommentAfterValueOnSameLine( const Value &root ) +{ + if ( root.hasComment( commentAfterOnSameLine ) ) + *document_ << " " + normalizeEOL( root.getComment( commentAfterOnSameLine ) ); + + if ( root.hasComment( commentAfter ) ) + { + *document_ << "\n"; + *document_ << normalizeEOL( root.getComment( commentAfter ) ); + *document_ << "\n"; + } +} + + +bool +StyledStreamWriter::hasCommentForValue( const Value &value ) +{ + return value.hasComment( commentBefore ) + || value.hasComment( commentAfterOnSameLine ) + || value.hasComment( commentAfter ); +} + + +std::string +StyledStreamWriter::normalizeEOL( const std::string &text ) +{ + std::string normalized; + normalized.reserve( text.length() ); + const char *begin = text.c_str(); + const char *end = begin + text.length(); + const char *current = begin; + while ( current != end ) + { + char c = *current++; + if ( c == '\r' ) // mac or dos EOL + { + if ( *current == '\n' ) // convert dos EOL + ++current; + normalized += '\n'; + } + else // handle unix EOL & other char + normalized += c; + } + return normalized; +} + + std::ostream& operator<<( std::ostream &sout, const Value &root ) { - Json::StyledWriter writer; - sout << writer.write(root); + Json::StyledStreamWriter writer; + writer.write(sout, root); return sout; }