Seconded. I was really disappointed with this book's lack of attention to detail and really poor, incomplete examples. For instance the "Delegation Pattern" is explained in screamingly complete UML glory but the farging example code (much more useful for the UML illiterate in the audience like me :) is so incredibly sketchy it merely hints at a complete usable implementation and then further obfuscates things by using tricks developers might use in the real world without explaining what they're doing. This book somehow succeeded in digging coal from a gold mine. Avoid it.