用Java语言实现上述jsp页面
时间: 2024-12-08 13:23:00 浏览: 10
在Java中实现这些JSP页面,我们可以使用Java Server Pages (JSP)结合Servlet(例如Java的HttpServlet)来处理后端逻辑。以下是一个简化的示例:
1. **login.jsp**:
```jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<title>Login</title>
</head>
<body>
<h1>Welcome to the site</h1>
<form action="LoginServlet" method="post">
<label for="name">Name:</label>
<input type="text" id="name" name="username" required><br>
<input type="submit" value="Login">
</form>
</body>
</html>
```
这里使用了 `<form>` 标签指向名为 `LoginServlet` 的后端处理器。
2. **LoginServlet.java** (back-end logic):
```java
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
public class LoginServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String username = request.getParameter("username");
if (username != null && !username.isEmpty()) {
// Save user's name in session or redirect to Main page
HttpSession session = request.getSession();
session.setAttribute("username", username);
RequestDispatcher rd = getServletContext().getRequestDispatcher("/main.jsp");
rd.forward(request, response);
} else {
// Redirect back to login page with error message
response.sendRedirect("login.jsp?error=username_required");
}
}
}
```
3. **main.jsp**:
```jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<title>Home</title>
</head>
<body>
<%@ include file="header.jsp" %>
<p>Welcome <%= session.getAttribute("username") %>, choose your products.</p>
<!-- Add product form and cart button -->
</body>
</html>
```
4. **header.jsp** (common header):
```jsp
<!-- Include this at the top of all pages -->
<h2>Header</h2>
```
5. **MainServlet.java** 或者 **ShoppingCartService.java** (for handling add-to-cart functionality):
```java
// This is where you handle adding items to the shopping cart
public class ShoppingCartService {
public static void addToCart(HttpServletRequest request, String productId) {
// Get the user's session and check if it exists
HttpSession session = request.getSession();
// Assuming a Vector<String> called cart is stored in session
Vector<String> cart = (Vector<String>) session.getAttribute("cart");
if (cart == null) {
cart = new Vector<>();
session.setAttribute("cart", cart);
}
// Add the product ID to the cart
cart.add(productId);
// Update shoppingCart.jsp with the new cart content
}
}
```
6. **shoppingCart.jsp**:
```jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
...
<%
Vector<String> cart = (Vector<String>) session.getAttribute("cart");
%>
<!-- Display user info, cart contents, and return link -->
...
```
以上是一个简化的示例,实际项目中还需要考虑错误处理、数据持久化等其他方面。记住要在web.xml文件中配置Servlet映射。
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