JSP页面中相关代码:
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
String url = "http://" + request.getServerName() + ":" +
request.getServerPort() +
request.getContextPath()+request.getServletPath().substring(0,request.getServletPath().lastIndexOf("/")+1);
if(request.getQueryString()!=null)
{
url+="?"+request.getQueryString();
}
System.out.println("path:"+path);
System.out.println("basePath:"+basePath);
System.out.println("URL:"+url);
System.out.println("URL参数:"+request.getQueryString());
%>
访问之后输出的结果:
1.这是不带参数
path:/CS
basePath:http://localhost:8080/CS/
URL:http://localhost:8080/CS/
URL参数:null
2.带参数时
path:/CS
basePath:http://localhost:8080/CS/
URL:http://localhost:8080/CS/?userid=3
URL参数:userid=3
为了在servlet中,让异常时跳到带有参数的URL,找了很久才找到。原来这么简单。把url存到session里,异常的时候再取出来加上去就好啦。
String url = session.getAttribute("url");
out.println("<script>alert(‘出错啦。‘);window.location.href=‘"+url+"‘;</script>");