Question

数据库之前一直可以用，突然就连接不上了，每个用到数据库的Java项目都连接不上了

Could not create connection to database server. Attempted reconnect 3 times. Giving up.at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.Util.getInstance(Util.java:381)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:984)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2270)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:723)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
Last packet sent to the server was 0 ms ago.

Answer 1

你先用plsql登录一下，看看能不能登录成功，如果不能，就是你的用户名和密码过期了

Answer 2

数据库服务器启动了么？

追问

显示服务器无法启动。不过能登录上数据库。我是新手，不清楚两者的关系，求指教谢谢的啊，我感觉之前服务器也没启动的。