大家看哈出错了！急...
今天上午的问题问的太多了居然没人回答！
于是我又查了一下资料！现在知道了自己的web页面应该建在D:\Tomcat\webapps\下，于是我在这下面建立了一个目录myapp
在D:\Tomcat\webapps\myapp下面有一个文件，和一个目录即：Time.jsp和WEB-INF目录（空的）
然后运行http://localhost:8080/myapp/Time.jsp   出错了！如下面：
HTTP   Status   500   -  

--------------------------------------------

type   Exception   report

message  

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.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:97)
org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:346)
org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:414)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:472)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:451)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:439)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:511)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:295)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)


root   cause  

Unable   to   find   a   javac   compiler;
com.sun.tools.javac.Main   is   not   on   the   classpath.
Perhaps   JAVA_HOME   does   not   point   to   the   JDK
org.apache.tools.ant.taskdefs.compilers.CompilerAdapterFactory.getCompiler(CompilerAdapterFactory.java:106)
org.apache.tools.ant.taskdefs.Javac.compile(Javac.java:935)
org.apache.tools.ant.taskdefs.Javac.execute(Javac.java:764)
org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:382)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:472)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:451)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:439)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:511)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:295)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)


note   The   full   stack   trace   of   the   root   cause   is   available   in   the   Apache   Tomcat/5.0.28   logs.


--------------------------------------------

Apache   Tomcat/5.0.28




------解决方案--------------------
不懂 帮顶下
------解决方案--------------------
Unable to find a javac compiler;
com.sun.tools.javac.Main is not on the classpath.
Perhaps JAVA_HOME does not point to the JDK

有没有tools.jar这个包啊，安装TOMCAT时有没有正确指定JDK的目录啊，JDK的环境变量有没有设对啊
------解决方案--------------------
你的Ｔomcat是安装版的？

那就是在设置jre的时候应该指向jdk，而不是jre,
jre只是运行环境，不会负责compile.



------解决方案--