myeclipse8.5导入项目后连不上mysql库了

2010-02-25 02:58:51 249 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

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Scratch-陶陶摘苹果 Scratch版-陶陶摘苹果（[蓝桥杯][算法]) 题目要求：陶陶家的院子里有一棵苹果树，每到秋天树上就会结出10个苹果。苹果成熟的时候，陶陶就会跑去摘苹果。陶陶有个30厘米高的板凳，当她不能直接用手摘到苹果的时候，就会踩到板凳上再试试。现在已知10个苹果到地面的高度，以及陶陶把手伸直的时候能够达到的最大高度，请帮陶陶算一下她能够摘到的苹果的数目。假设她碰到苹果，苹果就会掉下来。用scratch怎么完成呢？首先加入角色题目介绍接下来用询问框来录入苹果的高度并且记录到列表里数据初始化 . 阅读详情

同样的程序，用myelipse8.5编译过后运行出错。

org.apache.jasper.JasperException: java.lang.NullPointerException

	org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:532)

	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:426)

	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)

	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)

	javax.servlet.http.HttpServlet.service(HttpServlet.java:803)





root cause

日志:
2010-2-25 14:36:26 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
at java.util.Properties$LineReader.readLine(Unknown Source)
at java.util.Properties.load0(Unknown Source)
at java.util.Properties.load(Unknown Source)
at util.Database.init(Database.java:38)
at util.Database.<init>(Database.java:52)
at org.apache.jsp.index_jsp._jspService(index_jsp.java:87)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:384)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:228)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445)
at java.lang.Thread.run(Unknown Source)
可能是什么原因？

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