The Annoyance Filter.pdf - Fourmilab

§114 ANNOYANCE-FILTER FLASH TEXT EXTRACTOR 93
114. Flash text extractor.
The flashTextExtractor extends flashStream to parse tags containing text fields and return them
with the nextString method. We define this as a separate class in order to encapsulate all of the string
parsing machinery in one place, while leaving flashStream a general-purpose .swf file parser adaptable
to other purposes.
〈 Class definitions 10 〉 +≡
class flashTextExtractor : public flashStream {
protected: map〈unsigned short, vector〈unsigned short〉 ∗〉 fontMap;
map〈unsigned short, unsigned short〉 fontGlyphCount ;
map〈unsigned short, fontFlags〉 fontInfoBits ;
queue〈string〉 strings ;
bool initialised ; /∗ Options ∗/
bool textOnly ; /∗ Return only text (not font names, URLs, etc.) ∗/
public: flashTextExtractor(mailFolder ∗f = Λ)
: flashStream(f), initialised (false ), textOnly (false ) { }
∼flashTextExtractor( )
{
close ( );
}
virtual string name (void) const
{
return "Flash";
}
void setTextOnly (const bool tf )
{
textOnly = tf ;
}
bool getTextOnly (void) const
{
return textOnly ;
}
bool nextString (string &s); /∗ Return next string from Flash file ∗/
virtual void close (void)
{
while (¬fontMap.empty ( )) {
delete fontMap.begin ( ) ⃗ second ;
fontMap.erase (fontMap.begin ( ));
}
fontGlyphCount .clear ( );
fontInfoBits .clear ( );
while (¬strings .empty ( )) {
strings .pop( );
}
initialised = textOnly = false ;
flashStream ::close ( );
}
};