org.apache.jasper.JasperException: Unable to compile class for JSP:
An error occurred at line: 16 in the jsp file: /monday-01.jsp
System.out cannot be resolved to a type
13: <body>
14: <%
15: String a = request.getParameter("uname");
16: System.out.println("uname");
17:
18: %>
19:
Stacktrace:
org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:103)
org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:366)
org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:468)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:378)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:353)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:340)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:646)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:357)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
原因：问题的根本在于tomcat7中对java编译采用的是eclipse的ecj，而在最新版本的JDK17中，这个编译jar包已经过时了。
解决方法：方案一：tomcat7使用jsp，将JDK版本降到JDK1.7，即可解决版本冲突问题
方案二：将tomcat7升级到tomcat10，可以在JDK17环境下正常编译*_jsp文件
标签：01,java,monday,compile,jsp,jasper,apache,org From： https://www.cnblogs.com/yzx-sir/p/17436501.html