question: public void put ( String key , double value ) { if ( value == Double . POSITIVE_INFINITY ) { put ( key , "INF" ) ; } else if ( value == Double . NEGATIVE_INFINITY ) { put ( key , "-INF" ) ; } else { put ( key , Double . toString ( value ) ) ; } }
target:  Associates the specified double value with the specified key in this map. If the map previously contained a mapping for this key, the old value is replaced.