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                        /初識Java微信公眾號開發(fā)

請問微信可以回復“您發(fā)送的消息是：0”,為什么外網(wǎng)打開還是500空指針異常？

HTTP?Status?[500]???[Internal?Server?Error]
Type?Exception?Report
Description?The?server?encountered?an?unexpected?condition?that?prevented?it?from?fulfilling?the?request.
Exception
java.lang.NullPointerException
	java.util.ComparableTimSort.countRunAndMakeAscending(Unknown?Source)
	java.util.ComparableTimSort.sort(Unknown?Source)
	java.util.Arrays.sort(Unknown?Source)
	util.CheckUtil.checkSignature(CheckUtil.java:21)
	servlet.WeixinServlet.doGet(WeixinServlet.java:35)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
Note?The?full?stack?trace?of?the?root?cause?is?available?in?the?server?logs.
Apache?Tomcat/9.0.0.M21

這些都是什么意思??？