[news.eclipse.newcomer] Re: Cannot run help from eclipse

[J Michael Dean <mdean77@xxxxxxxxxxx>]

What is in your java extensions folder?  On Mac OS X, there is a place to
put jars that one wants to use (I think on Linux this will be in some bin
folder).  I found that if I put log4j.jar into my classpath, help stopped
working in Eclipse.  No idea why but when I took it out, Help worked
flawlessly.


On 3/4/05 1:25 PM, in article d0ag7j$8ib$1@xxxxxxxxxxxxxxx, "Bill Ferrett"
<billferrett@xxxxxxxxxxxxxxxx> wrote:

> I'm not exactly a newbie but I have always had problems running eclipse
> "Help Contents".  I am currently running 3.1.M5b but it has been the
> same story since 2.x.  A window opens, title
> "http://127.0.0.1/help/index.jsp"; but it is empty.  There do not appear
> to be any errors in the org.eclipse.tomcat log.
> 
> If I try "http://127.0.0.1"; from a browser I get "Internal Application
> Server" (so it must have been started) then I am redirected to an empty
> index.jsp page.
> 
> If I try "http://127.0.0.1/help/about.html"; I get the about.hmtl from
> "eclipse/plugins/org.eclipse.help.webapp_3.0.0".
> 
> So it looks like html files are served ok but the problem is jsp's.
> 
> When I try "http://127.0.0.1/help/index.jsp"; from a browser I get the
> following errors:
> 
> StandardWrapper[/help:org.eclipse.help.internal.webapp.jsp.basic.index_jsp]:
> Marking servlet org.eclipse.help.internal.webapp.jsp.basic.index_jsp as
> unavailable
> StandardWrapperValve[org.eclipse.help.internal.webapp.jsp.basic.index_jsp]:
> Allocate exception for servlet
> org.eclipse.help.internal.webapp.jsp.basic.index_jsp
> javax.servlet.ServletException: Error instantiating servlet class
> org.eclipse.help.internal.webapp.jsp.basic.index_jsp
> .
> 
> .
> 
> .
> 
> java.lang.LinkageError: loader constraints violated when linking
> javax/servlet/http/HttpServletResponse class
> 
> I have removed all versions of servlet.jar except that in
> eclipse\plugins\org.eclipse.tomcat_4.1.30 as I suspected there could be
> duplicate classes on the classpath.  I don't have a CLASSPATH envar.
> 
> Finally, if I put an index.jsp file in
> eclipse\plugins\org.eclipse.tomcat_4.1.30\webapps\ROOT and try
> "http:\\127.0.0.1\index.jsp" I get an Error 500 and the log contains:
> 
> Error compiling file:
> E:\Projects\Eclipse\.metadata\.plugins\org.eclipse.tomcat\ROOT\/index_jsp.java
>      [javac] Compiling 1 source file
>      [javac] 
> E:\Projects\Eclipse\.metadata\.plugins\org.eclipse.tomcat\ROOT\index_jsp.java:
> 3: 
> package javax.servlet does not exist
>      [javac] import javax.servlet.*;
> .
> 
> .
> 
> .
> 
> Info: Compile: 
> javaFileName=E:\Projects\Eclipse\.metadata\.plugins\org.eclipse.tomcat\ROOT\/i
> ndex_jsp.java
>      classpath=null
>       cp=null
>       work 
> dir=E:\Projects\Eclipse\.metadata\.plugins\org.eclipse.tomcat\ROOT
>      srcDir=E:\Projects\Eclipse\.metadata\.plugins\org.eclipse.tomcat\ROOT
>      include=index_jsp.java
> Exception compiling Compile failed; see the compiler error output for
> details.
> 
> Exception:
> Compile failed; see the compiler error output for details.
> at org.apache.tools.ant.taskdefs.Javac.compile(Javac.java:938)
> 
> So it seems that Eclipse still knows how to handle jsp's but the
> classpath is empty.
> 
> How can I find out what the classpath is used when "Help Content" fails?
> 
> All of this is straight out of the box so to speak.  I unzipped the
> install file, started it up and got these results.  After a day trying
> to fathom it out I'm still stumped.  The main reason for persevering is
> that I want to set up an Info Center for an app I'm developing and need
> to understand how the help component works.