the problem

The problem was this: plugins did not appear to work. I dutifully installed my standard plugin set using the Update Manager but discovered no evidence of the effort after a restart. Subclipse? Missing. Mousefeed? FindBugs? nWire? Missing!

(Want to skip to the solution without reading more?)

Help > About > Installation Details showed they were installed but none were shown on Features or Plug-ins tabs. Apparently installed doesn’t mean installed in the typical sense of the word.

troubleshooting

• starting eclipse with -clean didn’t seem to help
• starting eclipse with -consoleLog -debug didn’t turn up anything
• starting eclipse with -console and using the ss command on the osgi console did not turn up the wayward plugins

peer support via IRC

Misery loves company, as they say, so I went to #eclipse on IRC. After sharing my troubles and troubleshooting, a person with the nick paulweb515_ began helping me.

At this point, I determined my plugins were being installed in ~/.eclipse/.../features/ and ~/.eclipse/.../plugins/. Huh? What is this? Apparently that’s a feature of Eclipse. But I’m getting ahead of myself…

While in #eclipse I did some more extensive Google searching and turned up a bug report, titled Plugins install, but do not work, which seemed to mirror my problem.

The bug report indicated that Eclipse places plugins and features in ~/.eclipse/ when the user does not have sufficient permission for the eclipse program directory itself. As I wrote before, apparently that’s a feature. But, still, my plugins weren’t working!

the solution

My solution, then, is to install Eclipse in a location where the user has full rights. For Windows 7 users, a good location might be under the user’s home directory (%USERPROFILE%). Alternatively, the user could be granted full control of the Eclipse program directory.

While I’m glad my Eclipse is back to normal, I’m still disappointed in the amount of time wasted on the problem. And, unfortunately, I’ve not been able to determine if this ~/.eclipse/ feature is broken or if something else is going sideways.

Update: Looks like the author of nWire has posted about this issue.

To make Sun’s Java 6 JDK available on Ubuntu 10.04, 10.10 or later, add the new repository like so:

add-apt-repository "deb http://archive.canonical.com/ lucid partner" && aptitude update

Then, be sure to follow my previous instructions for installing the JDK.

Here are two examples:

diff -y <(sort file1) <(sort file2)

comm -3 <(sort file1) <(sort file2)

See this wikipedia entry for a comparison of the diff and comm commands.

Rather, I should say there are better ways: puttycyg and mintty.

puttycyg is a patched version of putty with support for cygwin. mintty is … well, yeah, it’s based on putty, too.

If you use cygwin, you owe it to yourself to try one or both of them immediately. And by that I mean stop reading and start downloading. Now.

To do so when using ehcache within a webapp, simply add its ShutdownListener as a listener in web.xml.

<listener>
    <listener-class>net.sf.ehcache.constructs.web.ShutdownListener</listener-class>
</listener>

Alternatively, or when not using ehcache inside a webapp, instruct ehcache to register its own shutdown hook by setting a system property.

net.sf.ehcache.enableShutdownHook=true

If you forget one of the above, your persisted cache may not be up-to-date, or worse, not persisted at all.

Here’s the default configuration for the version of Jetty I use. Note the element is commented.

<!--
<init-param>
      <param-name>cacheControl</param-name>
      <param-value>max-age=3600,public</param-value>
</init-param>
-->

To enable and configure browser cache control, uncomment and edit the param-value as appropriate. The following example instructs the browser to disable all caching.

<init-param>
      <param-name>cacheControl</param-name>
      <param-value>no-store,no-cache,must-revalidate</param-value>
</init-param>

For information on Cache-Control, see RFC 2616, Section 14.9.

But, don’t take its advice too literally… you may indeed have a configuration issue, but not with DocumentRoot. Be sure to check your Apache configuration for any overlapping/conflicting SVNParentPath and Alias entries!

At first I questioned the need to do anything at all — my computer apparently mounts my NTFS drive on its own but I couldn’t remember how.

Before I found the ultimate solution, one approach my coworker attemped was to have gnome execute a script at login which used the mount command. This didn’t work; he forgot to use gksudo and anyway the script never seemed to run.

Then I remembered fstab and the rest is history. If you need to accomplish the same thing, be sure to read his fstab blog post.

Moving the mouse over the graph will highlight and display the index for a given point in time. Clicking the mouse will advance to another city.

Posting this update reminds me I need to get back to reading Visualizing Data!

Oops, your browser does not have a Java Plug-in. Get the latest Java Plug-in here. Or, if you have Java but can’t use the Plug-in, feel free to download the program as an executable jar. Here’s a screen shot of what you’re missing.