package com;
import java.sql.*;
public class JDBConnection {
    private final String dbDriver = "com.microsoft.jdbc.sqlserver.SQLServerDriver"; //連接sql數據庫的方法
 private final String url = "jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=db_database19";
 private final String userName = "sa";
 private final String password = "";
 private Connection con = null;

 public JDBConnection() {
     try {
         Class.forName(dbDriver).newInstance(); //加載數據庫驅動
     } catch (Exception ex) {
         System.out.println("數據庫加載失敗");
     }
 }

//創建數據庫連接
 public boolean creatConnection() {
     try {
         con = DriverManager.getConnection(url, userName, password);
         con.setAutoCommit(true);
         return true;
     } catch (SQLException e) {
         System.out.println(e.getMessage());
         System.out.println("creatConnectionError!");
     return false;
     }

 }

//對數據庫的增加、修改和刪除的操作
 public boolean executeUpdate(String sql) {

     if (con == null) {
         creatConnection();
     }
     try {
         Statement stmt = con.createStatement();
         int iCount = stmt.executeUpdate(sql);
         System.out.println("操作成功，所影響的記錄數為" + String.valueOf(iCount));

           return true;
     } catch (SQLException e) {
         System.out.println(e.getMessage());
         System.out.println("executeUpdaterError!");
         return false;
     }

 }

//對數據庫的查詢操作
 public ResultSet executeQuery(String sql) {
     ResultSet rs;
     try {
         if (con == null) {
             creatConnection();
         }
         Statement stmt = con.createStatement();
         try {
             rs = stmt.executeQuery(sql);
         } catch (SQLException e) {
             System.out.println(e.getMessage());
             return null;
         }
     } catch (SQLException e) {
         System.out.println(e.getMessage());
         System.out.println("executeQueryError!");
         return null;
     }
     return rs;
 }

//關閉數據庫的操作
 public void closeConnection() {
     if (con != null) {
         try {
             con.close();
         } catch (SQLException e) {
             e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates.
             System.out.println("Failed to close connection!");
         } finally {
             con = null;
         }
     }
 }


}