java可以实现内存共享的，请看这是内存映射的源代码-java can achieve shared memory, which is memory Look at the source code for mapping

java语言编写的程序，完成一个多线程的文件共享服务器，可以控制允许连接数，以及可以设置多个共享目录-a program written in java, to complete a multi-threaded file-sharing server, you can control the number of connections allowed, and can set up multiple shared directories