1 Class.forName()加载驱动
2 DriverManager获取Connect连接
3 创建Statement执行SQL语句
4 返回ResultSet查询结果
5释放资源
java">package cn.tree.dao;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class MenuDao {
// 查询主目录
public void getMainList() {
Connection connection = null;
Statement st = null;
ResultSet rs = null;
try {
// 1、加载驱动
Class.forName("com.mysql.jdbc.Driver");
// 2、获取数据库连接
connection = DriverManager.getConnection(
"jdbc:mysql://127.0.0.1:3306/tree", "root", "123321");
// 3、获取Statement对象,执行sql语句
String sql = "select * from main";
st = connection.createStatement();
rs = st.executeQuery(sql);
// 4、处理sql执行结果
while (rs.next()) {
int id = rs.getInt("id");
String name = rs.getString("name");
System.out.println("id: " + id + "\t" + "name: " + name);
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {
// 5、释放资源
rs.close();
st.close();
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
public static void main(String[] args) {
MenuDao menuDao = new MenuDao();
menuDao.getMainList();
}
}