编写一个Servlet,读取两个请求参数first和second,将其转换为int值后相加,和存放在请求范围内,然后把请求转发第二个Servlet。第二个Servlet2向客户输出第一个Servlet的计算的结果。
时间: 2024-09-28 09:16:21 浏览: 5
在Java Servlet中编写这样的程序,你需要遵循以下步骤:
1. 创建`Servlet 1`(通常称为`FirstServlet`),首先需要导入相关的包,如`javax.servlet`, `javax.servlet.http`:
```java
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class FirstServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// 读取请求参数
String firstParam = request.getParameter("first");
String secondParam = request.getParameter("second");
// 将字符串转换为整数并求和
int sum;
try {
sum = Integer.parseInt(firstParam) + Integer.parseInt(secondParam);
} catch (NumberFormatException e) {
// 如果参数不是数字,处理错误
response.sendError(HttpServletResponse.SC_BAD_REQUEST, "Invalid parameters");
return;
}
// 存储计算结果到request范围,比如session属性或特定的request attribute
request.setAttribute("result", sum);
// 转发请求到下一个Servlet
RequestDispatcher dispatcher = request.getRequestDispatcher("/SecondServlet");
dispatcher.forward(request, response);
}
}
```
2. 创建`Servlet 2`(`SecondServlet`),它会从请求范围中获取并显示结果:
```java
import javax.servlet.*;
import javax.servlet.http.*;
public class SecondServlet extends HttpServlet {
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
int result = (int) request.getAttribute("result"); // 获取存储的结果
// 输出结果给客户端
response.setContentType("text/plain");
response.getWriter().println("The sum is: " + result);
}
}
```