package?demo;

import?java.sql.Connection;
import?java.sql.DriverManager;

public?class?DBConnection?{

	//?設(shè)置成私有的
	private?static?final?String?driver?=?“com.mysql.jdbc.Driver“;//?數(shù)據(jù)庫驅(qū)動
	private?static?final?String?url?=?“jdbc:mysql://localhost:3306/login“;
	private?static?final?String?username?=?“root“;?????????????????????????????????????????
	private?static?final?String?password?=?“root“;
	private?static?Connection?conn?=?null;
	//?靜態(tài)代碼塊加載數(shù)據(jù)庫驅(qū)動
	static?{
		try?{
			Class.forName（driver）;
		}?catch?（Exception?e）?{
			e.printStackTrace（）;
		}
	}

	//?單例模式返回?cái)?shù)據(jù)庫連接對象
	public?static?Connection?getConnection（）?throws?Exception?{
		if?（conn?==?null）?{

			conn?=?DriverManager.getConnection（url?username?password）;
			return?conn;
		}
		return?conn;
	}

	public?static?void?main（String[]?args）?{
		try?{
			Connection?conn?=?DBConnection.getConnection（）;
			if?（conn?!=?null）?{
				System.out.println（“數(shù)據(jù)庫連接正?！埃?
			}?else?{
				System.out.println（“數(shù)據(jù)庫連接異?！埃?
			}
		}?catch?（Exception?e）?{
			e.printStackTrace（）;
		}
	}

	
}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件????????939??2018-06-06?22:18??javaWebDemo\.classpath

?????文件????????911??2018-06-06?22:12??javaWebDemo\.project

?????文件????????567??2018-06-06?22:12??javaWebDemo\.settings\.jsdtscope

?????文件????????364??2018-06-06?22:12??javaWebDemo\.settings\org.eclipse.jdt.core.prefs

?????文件????????485??2018-06-06?22:12??javaWebDemo\.settings\org.eclipse.wst.common.component

?????文件????????345??2018-06-06?22:12??javaWebDemo\.settings\org.eclipse.wst.common.project.facet.core.xml

?????文件?????????49??2018-06-06?22:12??javaWebDemo\.settings\org.eclipse.wst.jsdt.ui.superType.container

?????文件??????????6??2018-06-06?22:12??javaWebDemo\.settings\org.eclipse.wst.jsdt.ui.superType.name

?????文件???????1571??2018-06-08?11:33??javaWebDemo\build\classes\demo\DBConnection.class

?????文件???????2491??2018-06-08?11:45??javaWebDemo\build\classes\demo\loginServlet.class

?????文件???????1610??2018-06-08?11:51??javaWebDemo\build\classes\demo\LoginSuccess.class

?????文件???????1177??2018-06-08?11:33??javaWebDemo\src\demo\DBConnection.java

?????文件???????1933??2018-06-08?11:45??javaWebDemo\src\demo\loginServlet.java

?????文件???????1041??2018-06-08?11:51??javaWebDemo\src\demo\LoginSuccess.java

?????文件????????745??2018-06-06?22:34??javaWebDemo\WebContent\index.jsp

?????文件????????401??2018-06-08?11:24??javaWebDemo\WebContent\login_failed.jsp

?????文件????????379??2018-06-08?12:14??javaWebDemo\WebContent\login_success.jsp

?????文件?????????39??2018-06-06?22:12??javaWebDemo\WebContent\meta-INF\MANIFEST.MF

?????文件?????848401??2017-10-27?08:25??javaWebDemo\WebContent\WEB-INF\lib\mysql-connector-java-5.1.25-bin.jar

?????文件????????911??2018-06-08?11:54??javaWebDemo\WebContent\WEB-INF\web.xml

?????目錄??????????0??2018-06-08?12:16??javaWebDemo\build\classes\demo

?????目錄??????????0??2018-06-08?12:16??javaWebDemo\WebContent\WEB-INF\lib

?????目錄??????????0??2018-06-08?12:16??javaWebDemo\build\classes

?????目錄??????????0??2018-06-08?12:16??javaWebDemo\src\demo

?????目錄??????????0??2018-06-08?12:16??javaWebDemo\WebContent\meta-INF

?????目錄??????????0??2018-06-08?12:16??javaWebDemo\WebContent\WEB-INF

?????目錄??????????0??2018-06-08?12:16??javaWebDemo\.settings

?????目錄??????????0??2018-06-08?12:16??javaWebDemo\build

?????目錄??????????0??2018-06-08?12:16??javaWebDemo\src

?????目錄??????????0??2018-06-08?12:16??javaWebDemo\WebContent

............此處省略4個文件信息