当jdbc驱动版本为8.0+时不设置时区会报错
- 修改url连接
String url = "jdbc:mysql://localhost:3306/javaweb?serverTimezone=GMT%2B8";
或者
String url = "jdbc:mysql://localhost:3306/javaweb?serverTimezone=Asia/Shanghai";
- 防止乱码
String url = "jdbc:mysql://localhost:3306/javaweb?serverTimezone=GMT%2B8&characterEncoding=utf8";
- 远程数据库连接
String url = "jdbc:mysql://xxx.xxx.xx.xx:3306/javaweb?serverTimezone=GMT%2B8&characterEncoding=utf8&useSSL=false&useUnicode=true";
获取连接
Class.forName("com.mysql.cj.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/javaweb?serverTimezone=GMT%2B8";
String username = "root";
String password = "root";
Connection con = DriverManager.getConnection(url,username,password);
System.out.println(con);
执行增删改语句
String sql = "insert into t_user values (?,?,?,?)";
PreparedStatement pre = conn.prepareStatement(sql);
pre.setInt(1,user.getUid());
pre.setString(2,user.getName());
pre.setInt(3,user.getAge());
pre.setString(4,user.getPhone());
//ResultSet resultSet = pre.executeQuery();
int i = pre.executeUpdate();
System.out.println(i);
执行查询语句
String select = "select * from t_user;";
PreparedStatement pre = conn.prepareStatement(select);
ResultSet res = pre.executeQuery();
List<User> list = new ArrayList<>();
while (res.next()) {
User user = new User();
user.setUid(res.getInt("uid"));
user.setName(res.getString("name"));
user.setAge(res.getInt("age"));
user.setPhone(res.getString("phone"));
list.add(user);
}
驱动下载地址
https://repo1.maven.org/maven2/mysql/mysql-connector-java/8.0.26/
maven
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.26</version>
</dependency>