Enumeration cannot be resolved to a type

程序员文章站 2022-04-25 21:25:22

...

An error occurred at line: 12 in the jsp file: /index.jsp
Enumeration cannot be resolved to a type
9: <body>
10: 	<%
11: 	    out.println("Hello Word!"); 
12: 	    Enumeration headerNames = request.getHeaderNames();
13: 	    while (headerNames.hasMoreElements()) {
14: 	        String paramName = (String) headerNames.nextElement();
15: 	        out.print("<tr><td>" + paramName + "</td>\n");


Stacktrace:] with root cause
org.apache.jasper.JasperException: Unable to compile class for JSP: 

An error occurred at line: 12 in the jsp file: /index.jsp
Enumeration cannot be resolved to a type
9: <body>
10: 	<%
11: 	    out.println("Hello Word!"); 
12: 	    Enumeration headerNames = request.getHeaderNames();
13: 	    while (headerNames.hasMoreElements()) {
14: 	        String paramName = (String) headerNames.nextElement();
15: 	        out.print("<tr><td>" + paramName + "</td>\n");


Stacktrace:
	at org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:103)
	at org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:366)
	at org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:468)
	at org.apache.jasper.compiler.Compiler.__compile(Compiler.java:378)
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java)
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java:353)
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java:340)
	at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:646)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:357)
	at org.apache.jasper.servlet.JspServlet._serviceJspFile(JspServlet.java:390)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
	at org.apache.catalina.core.StandardContextValve.__invoke(StandardContextValve.java:123)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
	at org.apache.catalina.core.StandardHostValve.__invoke(StandardHostValve.java:171)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)

解决方案:jsp页面需要引入:

<%@ page import="java.util.*"%>

Enumeration cannot be resolved to a type

PHP错误Cannot use object of type stdClass as array in错误的解决办法

PHP JSON出错：Cannot use object of type stdClass as array解决方法

遇见“The absolute uri: [http://java.sun.com/jsp/jstl/core] cannot be resolved..”怎么办

JSP报错javax.servlet.jsp.JspException cannot be resolved to a type solution

IOS开发遇到Interface type cannot be statically allocated 问题的解决办法

TypeError: POST data should be bytes, an iterable of bytes, or a file object. It cannot be of type s

TypeError: POST data should be bytes, an iterable of bytes, or a file object. It cannot be of type s

configure: error: cannot guess build type; you must specify one

The instance of entity type ‘xxx‘ cannot be tracked because another instance with the same key value

SpringBoot项目在启动时出现了Cannot determine embedded database driver class for database type NONE 错误