Below is the example source code from "TCP/IP Sockets in JavaTM: Practical Guide for Programmers, Second Edition" by Kenneth L. Calvert and Michael J. Donahoo. This book can be ordered at your favorite local bookstore or online.
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Disclaimer: The purpose of this book is to provide general information about network programming as of the book's publication date. The authors have included sample code that is intended for the sole purpose of illustrating the use of the sockets API. Neither the authors nor the publisher are aware of any third party patents or proprietary rights that may cover any sample of any kind. The authors and the Publisher DISCLAIM ALL EXPRESS AND IMPLIED WARRANTIES, including warranties of merchantability and fitness for any particular purpose. Your use or reliance upon any sample code or other information in this book will be at your own risk. No one should use any sample code (or illustrations) from this book in any software application without first obtaining competent legal advice.