java 从request中获取url
// 例子1
// http://localhost:8080/t***-web/sys/home/index.htm
String exm = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort() + request.getContextPath()+"/"+"sys/home/index.htm";
// 例子1
// http://localhost:8080/t***-web/sys/home/index.htm
String exm = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort() + request.getContextPath()+"/"+"sys/home/index.htm";