最简单的Java连oracle方法

package com.sun.ATest;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class Main {    private Connection conn = null;    private Statement stmt = null;    private ResultSet Rs = null;    public void test() {        // 创建数据库连接        try {            Class.forName("oracle.jdbc.driver.OracleDriver");            //DriverManager.getConnection(url, userName, password);            conn = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl", "test",  "wangjj");            stmt = conn.createStatement();            Rs = stmt.executeQuery("select sysdate from dual");            if (Rs.next()) {                 System.out.println(Rs.getString("SYSDATE")); //SYSDATE 不区分大小写                // System.out.println(Rs.getString(1)); //索引从 1 开始            }        } catch (ClassNotFoundException e) {            e.printStackTrace();        } catch (SQLException e) {            e.printStackTrace();        }               //关闭操作 数据集 会话 连接        try {            Rs.close();            stmt.close();            conn.close();        } catch (SQLException e) {            e.printStackTrace();        }    }    public static void main(String[] args) {        new Main().test();    }}