Question

我在将字符串返回到JSP页面上的组件时遇到了一些麻烦。我已经构建了一个非常简单的页面如下：

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
...
<div id="logindiv" class="centered">
        <h1>DB Schema status</h1>
    <form action="DBConnectionTester" method="post">

        <input type="text" name="usr" placeholder="DB Username" style="text-align: center;">
        <br>
        <input type="password" name="pwd" placeholder="DB Password" style="text-align: center;">
        <br>
        <input type="submit" value="Get Schema" class="btn btn-default btn-xs">
        <br>
        <br>
        <c:if test="${not empty rtnmsg}">
        <h6>${message}</h6>
        </c:if>
    </form>
    </div>

背后的课程如下：

@WebServlet("/DBConnectionTester")
public class DBConnectionTester extends HttpServlet {

String rtnmsg = "";

DBConnection dbcon = new DBConnection();
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
  dbcon.usr = request.getParameter("usr");
  dbcon.pwd = request.getParameter("pwd");        
  dbcon.sampletest();
  rtnmsg = dbcon.rtnstr;
}

}

为了澄清，DBConnection如下：

public class DBConnection {

public String usr;
public String pwd;

private static String mySQLCon = "jdbc:mysql://<REDACTED>zeroDateTimeBehavior=convertToNull";
public String err;
public String stmt;

public String rtnstr;

void sampletest()
{
   try 
    {
    Connection mCon = DriverManager.getConnection(mySQLCon, usr, pwd);
    mCon.getSchema();
    err = "No connection issues";
    }
    catch (SQLException e)
    {
        err = e.toString();
    } 
   Date date = new Date();
   rtnstr = err + date.toString();
}       
}

现在，每当我点击提交按钮时，我的浏览器似乎都会访问该类本身 - 也就是说，浏览器中的URL如下所示：http://<REDACTED>elasticbeanstalk.com/DBConnectionTester

我在这里缺少什么？

将消息返回到JSP

0 个答案: