Java Http会话计算_Java_Servlets

Java Http会话计算

java servlets

Java Http会话计算,java,servlets,Java,Servlets,我正在制作一个购物web应用程序，我有第一个html表单，如下所示： <!DOCTYPE html> <html> <head> <META HTTP-EQUIV="Pragma" CONTENT="no cache"> <META HTTP-EQUIV="Cache-control" CONTENT="no cache"> <META HTTP-EQUIV="Expires" CONT

我正在制作一个购物web应用程序，我有第一个html表单，如下所示：

<!DOCTYPE html>
<html>
<head>
    <META HTTP-EQUIV="Pragma" CONTENT="no cache">
    <META HTTP-EQUIV="Cache-control"
          CONTENT="no cache">
    <META HTTP-EQUIV="Expires" CONTENT="0">
    <TITLE>Shopping Cart</TITLE>
    <title> Shopping Cart </title>
</head>
<body>
<center>
    <h3> Simple Shopping Cart </h3>

    <form method=post action="Selection">

        <table>
            <tr>
                <td>
                    <input type="radio" name="Product" value="Apples" checked>
                    <font color=blue> Apples </font>
                </td>
            </tr>

            <tr>
                <td>
                    <input type="radio" name="Product" value="Pears">
                    <font color=blue> Pears </font>
                </td>
            </tr>
            <tr>
                <td>
                    <input type="radio" name="Product" value="Checkout">
                    <font color=blue> Go To the checkout </p> </font>
                </td>
            </tr>
        </table>
        <BR><BR><BR>
        <input type="submit" value="Submit">
    </form>
</center>
</body>
</html>

最后，这是Checkout Servlet：

我的问题是计算成本和总成本变量

结果，每个购物结帐都被指定为零

我的代码出了什么问题？

产品将其命名为所选产品的枚举，您希望将Apple与当前产品进行比较

替换

 if (prodNames.equals("Apples")) { // never true
     cost = APPLES_PRICE * wt;
 } else if (prodNames.equals("Pears")) { // never true
     cost = PEARS_PRICE * wt;
 }

与：

 if (product.equals("Apples")) {
     cost = APPLES_PRICE * wt;
 } else if (product.equals("Pears")) {
     cost = PEARS_PRICE * wt;
 }

顺便说一下，您应该了解如何调试应用程序。它将帮助您管理此类问题

 if (prodNames.equals("Apples")) { // never true
     cost = APPLES_PRICE * wt;
 } else if (prodNames.equals("Pears")) { // never true
     cost = PEARS_PRICE * wt;
 }

 if (product.equals("Apples")) {
     cost = APPLES_PRICE * wt;
 } else if (product.equals("Pears")) {
     cost = PEARS_PRICE * wt;
 }