以下内容由CHATGPT及阿里嘎多学长共同生成、有用望采纳:
根据您提供的文件内容和问题描述,您需要实现一个Java Web应用程序,其中前端使用JavaScript与后端进行交互,后端使用Java Servlet和JavaBean以及JSP技术来操作MySQL数据库。以下是根据您的需求提供的代码示例和步骤说明:
1. 创建Info类(JavaBean)
public class Info {
private int infoid;
private String infotitle;
private String infocontent;
// 构造函数
public Info() {
}
// getter和setter方法
public int getInfoid() {
return infoid;
}
public void setInfoid(int infoid) {
this.infoid = infoid;
}
public String getInfotitle() {
return infotitle;
}
public void setInfotitle(String infotitle) {
this.infotitle = infotitle;
}
public String getInfocontent() {
return infocontent;
}
public void setInfocontent(String infocontent) {
this.infocontent = infocontent;
}
}
2. 编写InfoDao类
import java.sql.*;
public class InfoDao {
private String url = "jdbc:mysql://localhost:3306/your_database";
private String user = "username";
private String password = "password";
public void DelInfo(int id) {
String sql = "DELETE FROM info WHERE infoid = ?";
try (Connection conn = DriverManager.getConnection(url, user, password);
PreparedStatement pstmt = conn.prepareStatement(sql)) {
pstmt.setInt(1, id);
pstmt.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
}
}
public Info GetInfo(int id) {
String sql = "SELECT * FROM info WHERE infoid = ?";
Info info = null;
try (Connection conn = DriverManager.getConnection(url, user, password);
PreparedStatement pstmt = conn.prepareStatement(sql)) {
pstmt.setInt(1, id);
ResultSet rs = pstmt.executeQuery();
if (rs.next()) {
info = new Info();
info.setInfoid(rs.getInt("infoid"));
info.setInfotitle(rs.getString("infotitle"));
info.setInfocontent(rs.getString("infocontent"));
}
} catch (SQLException e) {
e.printStackTrace();
}
return info;
}
}
3. 编写DelinfoServlet类
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.IOException;
public class DelinfoServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
int id = Integer.parseInt(request.getParameter("id"));
InfoDao infoDao = new InfoDao();
infoDao.DelInfo(id);
response.sendRedirect("index.jsp");
}
}
4. 编写GetinfoServlet类
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.IOException;
public class GetinfoServlet extends HttpServlet {
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
int id = Integer.parseInt(request.getParameter("id"));
InfoDao infoDao = new InfoDao();
Info info = infoDao.GetInfo(id);
if (info != null) {
request.setAttribute("info", info);
request.getRequestDispatcher("/showinfo.jsp").forward(request, response);
} else {
response.sendRedirect("index.jsp");
}
}
}
前端JSP页面示例
index.jsp
showinfo.jsp
<%@ page import="your.package.Info" %>
<% Info info = (Info) request.getAttribute("info"); %>
Info Details
Info Details
Info ID: <%= info.getInfoid() %>
Info Title: <%= info.getInfotitle() %>
Info Content: <%= info.getInfocontent() %>
请注意,您需要将数据库连接信息(URL、用户名、密码)替换为您自己的信息。另外,your_database和your.package也需要替换为您实际使用的数据库名称和Java包路径。
至于JavaScript前端连接MySQL数据库的实现,通常前端不直接与数据库交互,而是通过后端API进行。JavaScript可以通过AJAX请求与后端Servlet进行通信,然后Servlet再与数据库进行交互。如果您需要前端JavaScript代码示例,请告知,我可以提供相应的代码。
关于参考资料,您可以参考以下链接:
希望这些信息对您有所帮助!如果有其他问题或需要进一步的帮助,请随时提问。
