我已经听到后面课程才发现，现在卡在这里进行不下去了来求助老师，访问一直都是报500错误，Users_login.jsp一直存在问题，我发现哪怕我另开一个工程就单独放一个JSP 也是一样的500报错。。。求助大神~~~

HTTP Status 500 - Unable to compile class for JSP

type Exception report

message Unable to compile class for JSP

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

exception

org.apache.jasper.JasperException: Unable to compile class for JSP
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:585)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:356)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:396)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:340)
javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

root cause

java.lang.NullPointerException
org.apache.tomcat.util.descriptor.tld.TldResourcePath.hashCode(TldResourcePath.java:164)
java.util.HashMap.hash(HashMap.java:366)
java.util.HashMap.getEntry(HashMap.java:466)
java.util.HashMap.get(HashMap.java:421)
org.apache.jasper.compiler.TldCache.getTaglibXml(TldCache.java:95)
org.apache.jasper.compiler.TagLibraryInfoImpl.<init>(TagLibraryInfoImpl.java:174)
org.apache.jasper.compiler.Parser.parseTaglibDirective(Parser.java:411)
org.apache.jasper.compiler.Parser.parseDirective(Parser.java:469)
org.apache.jasper.compiler.Parser.parseElements(Parser.java:1430)
org.apache.jasper.compiler.Parser.parse(Parser.java:139)
org.apache.jasper.compiler.ParserController.doParse(ParserController.java:227)
org.apache.jasper.compiler.ParserController.parse(ParserController.java:100)
org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:199)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:356)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:336)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:323)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:570)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:356)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:396)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:340)
javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

note The full stack trace of the root cause is available in the Apache Tomcat/8.0.17 logs.

Apache Tomcat/8.0.17