com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException：连接关闭但没有tcp套接字重置后不允许任何操作

My app got the error:

我的应用程序出错了:

Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.
        at sun.reflect.GeneratedConstructorAccessor281.newInstance(Unknown Source)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        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)
Caused by: