• 建立配置檔案 在專案跟目錄下，建立檔案，輸入“database.properties”檔名。(src下new一個file型別) 檔案中的內容 driverClass=com.mysql.jdbc.Driver url=jdbc:mysql://localhost:3306/mydb username=root password=123456
• 載入配置檔案：Properties物件

import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.util.Properties;
 


/*
*  編寫JDBC的工具類，獲取資料庫的連線
*  採用讀取配置檔案的方式
*  讀取配置檔案，獲取連線，執行一次，static{}
*/
public class JDBCUtilsConfig {
   private static Connection con;
   private static String driverClass;
   private static String url;
   private static String username;
   private static String password;
   static {
   	try {
   		readConfig
 
();
   		Class.forName(driverClass);
   		con = DriverManager.getConnection(url, username,
   				password);
   	} catch (Exception ex) {
   		throw new RuntimeException("資料庫連線失敗");
   	}
   }
   private static void readConfig() throws Exception {
   	InputStream in = JDBCUtilsConfig.class.getClassLoader
 
()
   			.getResourceAsStream("database.properties");
   	Properties pro = new Properties();
   	pro.load(in);
   	//使用getProperty(key)，通過key獲得需要的值
   	driverClass = pro.getProperty("driverClass");
   	url = pro.getProperty("url");
   	username = pro.getProperty("username");
   	password = pro.getProperty("password");
   }
   public static Connection getConnection() {
   	return con;
   }
   public static void main(String[] args) {
   }
}

• 測試類

import java.sql.Connection;
import util.JDBCUtilsConfig;
public class TestJDBCUtils {
	public static void main(String[] args) {
		Connection con = JDBCUtilsConfig.getConnection();
		System.out.println(con);	
	}
}