public class JDBCConnectionTest {
    public static void main(String[] args) {
        
        //Connection对象； 
        Connection conn = null;
        //Statement对象
        Statement stmt = null;
        //Result rs对象
        ResultSet rs = null;
        try {
            //加载驱动
            Class.forName("oracle.jdbc.driver.OracleDriver");
            //获取数据库连接对象(这里用到oracle连接对象)；
            conn = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:ORCL","ZZTEST","ZZTEST");
            //通过获取 数据库连接对象获取一个statement对象；
            stmt = conn.createStatement();
            //通过statement对象执行sql语句，查询操作用executeQuery()，增删改用executeUpdate()
            rs = stmt.executeQuery("select * from user");
            //去取出结果集数据输出到控制台
            System.out.println("============================");
            while(rs.next()) {
                int oid = rs.getInt("USER_USERID");
                String name = rs.getString("USER_NAME");
                String passwd = rs.getString("USER_PWD");
                System.out.println(oid+"\t"+name+"\t"+passwd);
            }
        }catch(Exception e) {
            e.getStackTrace();
        }finally {
            try {
                if(rs != null) {
                    rs.close();
                }
                if(stmt!= null) {
                    stmt.close();
                }
                if(conn!=null) {
                    conn.close();
                }
            }catch(Exception e){
                e.printStackTrace();
            }
        }
        
    }
}