Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: /inform_LED.jsp(1,1) Page-encoding specified in XML prolog (UTF-8) is different from that specified in page directive (utf-8)
	at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:40)
	at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:407)
	at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:236)
	at org.apache.jasper.compiler.Validator$DirectiveVisitor.comparePageEncodings(Validator.java:362)
	at org.apache.jasper.compiler.Validator$DirectiveVisitor.visit(Validator.java:197)
	at org.apache.jasper.compiler.Node$PageDirective.accept(Node.java:590)
	at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2336)
	at org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2386)
	at org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2392)
	at org.apache.jasper.compiler.Node$Root.accept(Node.java:489)
	at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2336)
	at org.apache.jasper.compiler.Validator.validate(Validator.java:1700)
	at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:178)
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java:306)
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java:286)
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java:273)
	at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:566)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:317)
	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.ApplicationDispatcher.invoke(ApplicationDispatcher.java:654)
	at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:445)
	at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:379)
	at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:292)
	at cn.com.servlet.Inform_LED.doPost(Inform_LED.java:290)
	at cn.com.servlet.Inform_LED.doGet(Inform_LED.java:23)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
	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:230)
	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:261)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:581)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
	at java.lang.Thread.run(Thread.java:744)
 

原因：

jsp頁面的pageEncoding設定和web.xml中的jsp-property-group的pageEncoding屬性設定不一致引起的。

解決辦法：

方法一、

在jsp的第一行加上

<%@ page language="java" import="java.util.*" contentType="text/html; charset=UTF-8" pageEncoding="utf-8"%>

應用下的WEB-INF中的web.xml中的設定

<jsp-config>
        <jsp-property-group>
            <description> Special property group for JSP Configuration JSP
                example. </description>
            <display-name>JSPConfiguration</display-name>
            <url-pattern>*.jsp</url-pattern>
            <el-ignored>true</el-ignored>
            <page-encoding>utf-8</page-encoding>
            <scripting-invalid>false</scripting-invalid>           
        </jsp-property-group>
    </jsp-config>

這兩者要一致。

方法二、

tomcat的原因，不用myeclipse自帶的myelipse tomcat,用