今天下午连接数据库，半成品
jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>添加信息</title>
<script>
function submitButtonClick() {
let className = document.getElementById("className").value;
let classTeacher = document.getElementById("classTeacher").value;
let classPlace = document.getElementById("classPlace").value;
if (!(classTeacher=="王建民" || classTeacher=="刘立嘉"|| classTeacher=="刘丹"||
classTeacher=="杨子光" || classTeacher=="张云霞" || classTeacher=="武勇亮" ||
classTeacher=="高飞" || classTeacher=="孙静")) {
alert("Teacher Error");
return;
}
if (classPlace[1] !== "教") {
alert("Addr Error");
return;
}
let xmlHttp = new XMLHttpRequest();
xmlHttp.open("POST","addInfo",false);
xmlHttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xmlHttp.send("className=" + className + "&classTeacher=" + classTeacher + "&classPlace=" + classPlace);
}
</script>
</head>
<body>
<label for="className">课程名称:</label>
<input type="text" id="className" name="className" required>
<br>
<label for="classTeacher">任课教师:</label>
<input type="text" id="classTeacher" name="classTeacher" required>
<br>
<label for="classPlace">上课地点:</label>
<input type="text" id="classPlace" name="classPlace" required><br>
<button id="submitButton" onclick="submitButtonClick()">Go!</button>
</body>
</html>
java1
package com.example.demo;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@WebServlet("/addInfo")
public class AddInfoServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
Connection connection = null;
try {
String driver = "com.mysql.cj.jdbc.Driver";
String url = "jdbc:mysql://localhost:3306/class";
String user = "root";
String password = "123567";
Class.forName(driver);
connection = DriverManager.getConnection(url, user, password);
if (connection != null) {
System.out.println("数据库连接成功！");
} else {
System.out.println("数据库连接失败！");
}
String className = request.getParameter("className");
String classTeacher = request.getParameter("classTeacher");
String classPlace = request.getParameter("classPlace");
System.out.println(className);
System.out.printf(classTeacher);
System.out.println(classPlace);
String insertSQL = "INSERT INTO class2 (className, classTeacher, classPlace) VALUES (?, ?, ?)";
PreparedStatement preparedStatement = connection.prepareStatement(insertSQL);
preparedStatement.setString(1, className);
preparedStatement.setString(2, classTeacher);
preparedStatement.setString(3, classPlace);
int rowsAffected = preparedStatement.executeUpdate();
System.out.println(rowsAffected + " 行数据已插入。");
preparedStatement.close();
} catch (ClassNotFoundException | SQLException e) {
e.printStackTrace();
} finally {
try {
if (connection != null) {
connection.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
java2
package com.example.demo;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DatabaseConnection {
public static Connection getConnection() throws SQLException, ClassNotFoundException {
String driver = "com.mysql.cj.jdbc.Driver";
String url = "jdbc:mysql://localhost:3306/class";
String user = "root";
String password = "123567";
Class.forName(driver);
return DriverManager.getConnection(url, user, password);
}
}
java3
package com.example.demo;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
public class MySQLConnection {
public static void main(String[] args) {
Connection connection = null;
try {
String driver = "com.mysql.cj.jdbc.Driver";
String url = "jdbc:mysql://localhost:3306/class";
String user = "root";
String password = "123567";
Class.forName(driver);
connection = DriverManager.getConnection(url, user, password);
if (connection != null) {
System.out.println("数据库连接成功！");
} else {
System.out.println("数据库连接失败！");
}
} catch (ClassNotFoundException | SQLException e) {
e.printStackTrace();
}
try {
String insertSQL = "INSERT INTO class2 (className, classTeacher,classPlace) VALUES (?, ?,?)";
// 创建PreparedStatement对象
PreparedStatement preparedStatement = connection.prepareStatement(insertSQL);
preparedStatement.setString(1, "Tm"); // 设置第一个参数值
preparedStatement.setString(2, "Tm"); // 设置第二个参数值
preparedStatement.setString(3, "Tm"); // 设置第三个参数值
int rowsAffected = preparedStatement.executeUpdate(); // 执行插入操作并返回受影响的行数
System.out.println(rowsAffected + " 行数据已插入。");
preparedStatement.close();
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {
if (connection != null) {
connection.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
标签：preparedStatement,java,String,10.9,数据库,半成品,connection,import,classTeacher From： https://www.cnblogs.com/xuxingkai/p/17753291.html