问题描述：我用Navicat可以正常的连接到数据库，但是通过程序连接的时候就报错如下，另外一个很奇怪的现象就是我再公司的时候连公司的网络就可以正常启动，回到家后连家里的网络就始终报错。在网上搜有一个相似的问题，可是我试了下还是不行。不知道问题出在哪里，求助.
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:408)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1137)
at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:674)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1086)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2508)
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2346)
... 93 more
Caused by: java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(SocketInputStream.java:209)
at java.net.SocketInputStream.read(SocketInputStream.java:141)
at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:112)
at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:159)
at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:187)
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3158)
at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:598)
... 96 more
