Added StyledStreamWriter, which has no reason to derive from Writer, since its write() method does cannot return a string and must take a stream.
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 @@
{
public:
FastWriter();
+ virtual ~FastWriter(){}
void enableYAMLCompatibility();
@@ -61,7 +62,7 @@
*
* \sa Reader, Value, Value::setComment()
*/
- class JSON_API StyledWriter
+ class JSON_API StyledWriter: public Writer
{
public:
StyledWriter();
@@ -98,13 +99,71 @@
bool addChildValues_;
};
+ /** \brief Writes a Value in <a HREF="http://www.json.org">JSON</a> 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 <a HREF="http://www.json.org">JSON</a> 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<std::string> 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 @@
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;
}