求高手进！！sqlserver+jdbc连接的错误

具体的错误就是这个了java.sql.SQLException: I/O Error: DB server closed connection.
        at net.sourceforge.jtds.jdbc.TdsCore.nextToken(TdsCore.java:2307)
        at net.sourceforge.jtds.jdbc.TdsCore.login(TdsCore.java:602)
        at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java
:344)
        at net.sourceforge.jtds.jdbc.ConnectionJDBC3.<init>(ConnectionJDBC3.java
:50)
        at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:182)
        at java.sql.DriverManager.getConnection(Unknown Source)
        at java.sql.DriverManager.getConnection(Unknown Source)
        at com.thomas.staticpage.Servlet.addart.doPost(addart.java:39)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Appl
icationFilterChain.java:269)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationF
ilterChain.java:188)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperV
alve.java:210)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextV
alve.java:174)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.j
ava:127)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.j
ava:117)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineVal
ve.java:108)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.jav
a:151)
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java
:870)
        at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.p
rocessConnection(Http11BaseProtocol.java:665)
        at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpo
int.java:528)
        at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFol
lowerWorkerThread.java:81)
        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadP
ool.java:685)
        at java.lang.Thread.run(Unknown Source)
Caused by: java.io.IOException: DB server closed connection.
        at net.sourceforge.jtds.jdbc.SharedSocket.readPacket(SharedSocket.java:8
43)
        at net.sourceforge.jtds.jdbc.SharedSocket.getNetPacket(SharedSocket.java
:722)
        at net.sourceforge.jtds.jdbc.ResponseStream.getPacket(ResponseStream.jav
a:466)
        at net.sourceforge.jtds.jdbc.ResponseStream.read(ResponseStream.java:103
)
        at net.sourceforge.jtds.jdbc.TdsCore.nextToken(TdsCore.java:2202)
        ... 23 more
I/O Error: DB server closed connection.