急急急，很急 ！求解JavaWeb异常！！！！
HTTP Status 500 - 

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type Exception report

message 

description The server encountered an internal error () that prevented it from fulfilling this request.

exception 

java.lang.NullPointerException
wyf.wyy.DateUtil.changeStringToDate(DateUtil.java:26)
wyf.wyy.DateUtil.getDay(DateUtil.java:5)
wyf.wyy.StuDB.getCurMoney(StuDB.java:138)
wyf.wyy.StuDB.getStuInfo(StuDB.java:55)
wyf.wyy.StudentServlet.doPost(StudentServlet.java:38)
javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


note The full stack trace of the root cause is available in the Apache Tomcat/6.0.18 logs.


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2012-4-13 21:13:02 org.apache.catalina.core.AprLifecycleListener init
信息: The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: D:\java\Common\binary\com.sun.java.jdk.win32.x86_1.6.0.013\bin;D:\Downloads\Apache Software Foundation\Tomcat 6.0\bin
2012-4-13 21:13:02 org.apache.coyote.http11.Http11Protocol init
信息: Initializing Coyote HTTP/1.1 on http-8080
2012-4-13 21:13:02 org.apache.catalina.startup.Catalina load
信息: Initialization processed in 460 ms
2012-4-13 21:13:02 org.apache.catalina.core.StandardService start
信息: Starting service Catalina
2012-4-13 21:13:02 org.apache.catalina.core.StandardEngine start
信息: Starting Servlet Engine: Apache Tomcat/6.0.18
2012-4-13 21:13:03 org.apache.catalina.core.ApplicationContext log
信息: Initializing Spring root WebApplicationContext
2012-4-13 21:13:03 org.springframework.web.context.ContextLoader initWebApplicationContext
信息: Root WebApplicationContext: initialization started
2012-4-13 21:13:04 org.springframework.context.support.AbstractApplicationContext prepareRefresh
信息: Refreshing org.springframework.web.context.support.XmlWebApplicationContext@1d6b049: display name [Root WebApplicationContext]; startup date [Fri Apr 13 21:13:04 CST 2012]; root of context hierarchy
2012-4-13 21:13:04 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from ServletContext resource [/WEB-INF/appcontext.xml]
2012-4-13 21:13:04 org.springframework.context.support.AbstractApplicationContext obtainFreshBeanFactory
信息: Bean factory for application context [org.springframework.web.context.support.XmlWebApplicationContext@1d6b049]: org.springframework.beans.factory.support.DefaultListableBeanFactory@135f7f3
2012-4-13 21:13:04 org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons
信息: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@135f7f3: defining beans [bookDataSource,jdbcTemplate,StuDB,DBUtil]; root of factory hierarchy
2012-4-13 21:13:05 org.springframework.web.context.ContextLoader initWebApplicationContext
信息: Root WebApplicationContext: initialization completed in 1110 ms
2012-4-13 21:13:05 org.apache.coyote.http11.Http11Protocol start
信息: Starting Coyote HTTP/1.1 on http-8080
2012-4-13 21:13:05 org.apache.jk.common.ChannelSocket init
信息: JK: ajp13 listening on /0.0.0.0:8009
2012-4-13 21:13:05 org.apache.jk.server.JkMain start
信息: Jk running ID=0 time=0/31 config=null
2012-4-13 21:13:05 org.apache.catalina.startup.Catalina start
信息: Server star