63 lines
2.7 KiB
Java
63 lines
2.7 KiB
Java
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package com.demo;
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import java.io.IOException;
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import javax.servlet.*;
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import javax.servlet.annotation.WebServlet;
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import javax.servlet.http.*;
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import java.sql.*;
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@WebServlet("/BookQueryServlet")
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public class BookQueryServlet extends HttpServlet {
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private static final long serialVersionUID = 1L;
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// 数据库连接信息常量
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// private static final String DB_URL = "jdbc:mysql://47.242.181.61:33060/demo?useSSL=false&serverTimezone=UTC";
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private static final String DB_URL = "jdbc:mysql://47.242.181.61:33060/demo?useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true";
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private static final String DB_USER = "root";
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private static final String DB_PASSWORD = "lotus";
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protected void doPost(HttpServletRequest request, HttpServletResponse response)
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throws ServletException, IOException {
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String bookid = request.getParameter("bookid");
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if (bookid == null || bookid.trim().isEmpty()) {
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request.setAttribute("error", "图书ID不能为空");
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request.getRequestDispatcher("/error.jsp").forward(request, response);
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return;
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}
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try (Connection conn = getConnection();
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PreparedStatement pstmt = conn.prepareStatement("SELECT * FROM books WHERE bookid = ?");
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) {
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pstmt.setString(1, bookid);
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try (ResultSet rst = pstmt.executeQuery()) {
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if (rst.next()) {
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BookBean book = new BookBean();
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book.setBookid(rst.getString("bookid"));
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book.setTitle(rst.getString("title"));
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book.setAuthor(rst.getString("author"));
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book.setPrice(rst.getFloat("price"));
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book.setPublisher(rst.getString("publisher"));
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request.setAttribute("book", book);
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request.getRequestDispatcher("/displayBook.jsp").forward(request, response);
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} else {
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request.setAttribute("error", "未找到ID为 " + bookid + " 的图书");
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request.getRequestDispatcher("/error.jsp").forward(request, response);
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}
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}
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} catch (Exception e) {
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String errorMsg = "数据库操作失败: " + e.getMessage();
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log(errorMsg, e);
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request.setAttribute("error", errorMsg);
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request.getRequestDispatcher("/error.jsp").forward(request, response);
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}
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}
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private Connection getConnection() throws SQLException, ClassNotFoundException {
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Class.forName("com.mysql.cj.jdbc.Driver");
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return DriverManager.getConnection(DB_URL, DB_USER, DB_PASSWORD);
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}
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}
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