jdbc 使用properties导入数据库信息2

使用：props.load(DBUtils.class.getClassLoader().getResourceAsStream("day01/db.properties"));导入配置文件使用的是反射机制.class ///获得Class对象.class.getClassLoader() ///获得ClassLoader对象.class.getClassLoader().getResourceAsStream(String name); //获得inputStream对象所以括号里是inputStream对象 这肯定是不变的///DBUtils.javapackage day02;
import java.io.File;import java.io.FileInputStream;import java.sql.Connection;import java.sql.DriverManager;import java.util.Properties;
public class DBUtils {private static String driver;private static String url;private static String user;private static String password;static{try{Properties props = new Properties();//从类路径中加载文件props.load(DBUtils.class.getClassLoader().getResourceAsStream("day01/db.properties"));//props.load(new FileInputStream("db.properties"));driver = props.getProperty("driver");url = props.getProperty("url");user = props.getProperty("user");password = props.getProperty("password");System.out.println(driver);System.out.println(url);System.out.println(user);Class.forName(driver);}catch(Exception e){throw new RuntimeException(e);}}public static Connection openConnection() throws Exception{ //静态方法获得连接Connection con = DriverManager.getConnection(url,user,password);return con;}}