java 연결 데이터베이스 (코드 공유)

package com.shsxt.jdbcs;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
/*
 * jdbc ： java 
 *  //   jar 
 *   1、    
 *   2、     url    
 *   3、    SQL （ ）   SQL 
 *   4、 
 *   5、 
 *   6、    ，  
 */
public class Demo002JDBCConnect {
  public static void main(String[] args) throws ClassNotFoundException {
    Class.forName("oracle.jdbc.driver.OracleDriver");
    String url = "jdbc:oracle:thin:@localhost:1521:orcl";
    String user=  "scott";
    String pwd=  "tiger";
    Connection conn = null;
    Statement s = null;
    ResultSet rs = null;
    try {
      conn = DriverManager.getConnection(url, user, pwd);
      s = conn.createStatement();
      String sql = "select deptno, dname, loc from dept";
      rs = s.executeQuery(sql);
      while(rs.next()){
        int deptno = rs.getInt(1); //  
        String dname = rs.getString("dname"); //  
        String loc = rs.getString(3);
        System.out.println(deptno + "\t" + dname + "\t" + loc);
      }
    } catch (SQLException e) {
      e.printStackTrace();
    }finally{
      if(rs!=null){
        try {
          rs.close();
        } catch (SQLException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }
      }
      if(s!=null){
        try {
          s.close();
        } catch (SQLException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }
      }
      if(conn!=null){
        try {
          conn.close();
        } catch (SQLException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }
      }
    }
  }
}