连接数据库

Class.forName();
Connection con = DriverMessage.connection();
Statement state = con.statement();
String sql = "";
int count = state.executeUpdate(sql);
if........

Class.forName("com.mysql.jdbc.Driver");
//DriverManager.getConnection("jdbc:mysql://localhost:3308/java31?characterEncoding = utf8", "root", "123456");
String url = "jdbc:mysql://localhost:3308/java31?characterEncoding = utf8";
Properties properties = new Properties();
properties.setProperty("user","root");
properties.setProperty("password","123456");
Connection connection = DriverManager.getConnection(url, properties);
String sql = "update account set balance = 20000 where username = '张三' ";
Statement statement = connection.createStatement();
int count = statement.executeUpdate(sql);
if (count > 0) {
System.out.println("更新数据库成功");
}else {
System.out.println("更新数据库失败");
}
statement.close();
connection.close();
}