[java学习12]servlet连接mysql数据库

た入场券 2022-07-15 09:44 153阅读 0赞

package firstServletPackage;
    
    import javax.servlet.ServletException;
    import javax.servlet.annotation.WebServlet;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import java.io.IOException;
    import java.io.PrintWriter;
    import java.sql.*;
    
    /** * Created by liyanq on 16/11/11. */ @WebServlet(name = "runoobServlet")
    public class runoobServlet extends HttpServlet {
        private static final long serialVersionUID = 1L;
    
        private static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
        private static final String DB_URL = "jdbc:mysql://localhost:3306/testMySQLdb";
    
        private static final String userName = "root";
        private static final String passWord = "12345";
    
        protected void doPost(HttpServletRequest request, HttpServletResponse response)
                throws ServletException, IOException {
            doGet(request, response);
        }
    
        protected void doGet(HttpServletRequest request, HttpServletResponse response)
                throws ServletException, IOException {
            response.setContentType("text/html;charset=UTF-8");
            PrintWriter writer = response.getWriter();
            writer.println("<!DOCTYPE html>");
            writer.println("<html>");
            writer.println("<head><title>测试连接数据库</title></head>");
            writer.println("<body>");
            writer.println("<h1 align=\"center\">测试连接数据库</h1>");
            Connection connection = null;
            Statement statement = null;
            try {
                Class.forName(this.JDBC_DRIVER);
                connection = DriverManager.getConnection(DB_URL, userName, passWord);
                statement = connection.createStatement();
                String string = "select * from websites";
                ResultSet resultSet = statement.executeQuery(string);
                while (resultSet.next()) {
                    int id = resultSet.getInt("id");
                    String name = resultSet.getString("name");
                    String url = resultSet.getString("url");
                    writer.println("ID:" + id);
                    writer.println(",站点名称：" + name);
                    writer.println(",url：" + url);
                }
                writer.println("</body></html>");
                resultSet.close();
                statement.close();
                connection.close();
            } catch (SQLException se) {
                se.printStackTrace();
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                try {
                    if (statement != null) {
                        statement.close();
                    }
                } catch (SQLException e1) {
                    try {
                        if (connection != null) {
                            connection.close();
                        }
                    } catch (SQLException e2) {
                        e2.printStackTrace();
                    }
                }
            }
        }
    }

http://www.runoob.com/java/java-mysql-connect.html