UseServlet.java

@WebServlet("/user.do")
public class UseServlet extends HttpServlet{

    private static final long serialVersionUID = 1L;
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        //設(shè)置字符集格式為utf-8
        //req.setCharacterEncoding("UTF-8");
        String scheme=req.getScheme();//獲取請求協(xié)議http
        String serverName=req.getServerName();//獲取服務(wù)器名稱localhost
        int serverPort = req.getServerPort();
        String contextPath=req.getContextPath();//返回Web應(yīng)用的URL入口
        String path=scheme+"://"+serverName+":"+serverPort+"/"+contextPath+"/";
        //getRealPath返回一個(gè)給定虛擬路徑的真實(shí)路徑
        String realPath=this.getServletContext().getRealPath("index.jsp");
        req.setAttribute("path", path);
        req.setAttribute("realPath", realPath);
        
        req.getRequestDispatcher("index.jsp").forward(req, resp);
        
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        doPost(req, resp);
    }
}

index.jsp

<form action="user.do" method="post">
        <table align="center">
            <tr>
                <td>Web路徑：</td>
                <td><%=(String)request.getAttribute("path") %></td>
            </tr>
            <tr>
                <td>真實(shí)路徑：</td>
                <td><%=(String)request.getAttribute("realPath") %></td>
            </tr>
            <tr>
                <td colspan="2" align="center">
                <input type="submit" value="獲取路徑"/>
                <input type="reset" value="重置"/>
                </td>
            </tr>
        </table>
    </form>

26.PNG