点广播是一种想当新的技术，可以将信息发送给那些等待接收信息接收者。利用Java的组播技术，设计一个网络广播系统，定时广播指定的内容。-Point radio is a want new technology, you can send information to those who wait for the receiver to receive information. Multicast using Java technology, design a network broadcasting system, specify the contents of the regular broadcast.