betweenGo

To turn off JSP access in your JBoss or other favorite application server add this to your web.xml.

<!-- Restrict direct access to jsps -->
<security-constraint>
  <web-resource-collection>
    <web-resource-name>you_cant_touch_this</web-resource-name>
    <url-pattern>*.jsp</url-pattern>
  </web-resource-collection>
  <auth-constraint/>
</security-constraint>

To prevent Apache from sending JSP requests to JBoss add the following to your configuration.

## DISALLOW FROM REACHING JBOSS (security-related filter):
!/*.jsp=name_of_your_app
!/*.xml=name_of_your_app

Previously I was using an old Maven integration for Eclipse, version 0.0.11, which I got from http://m2eclipse.codehaus.org/update.  The plugin was horribly slow and seemed to sometimes interfere with my builds.

Today I upgraded to the latest, version 0.9.4, from http://m2eclipse.sonatype.org/update/ and things are moving much more smoothly.  You can learn more at Maven Integration for Eclipse.

Now if someone would improve the Perforce plugin…

In JBoss 4.0.4.GA it took me awhile to figure out how to enable trace level debugging.

Typically you could do something like this to enable trace level debugging for a category of classes.

<category  name="com.betweengo.app">
  <priority  value="TRACE"/>
</category>

However JBoss 4.0.4.GA has an older log4j implementation so you need to use JBoss’s custom TRACE level.

<category  name="com.betweengo.app">
  <priority  value="TRACE" class="org.jboss.logging.XLevel"/>
</category>

This is documented in the release notes for JBoss-4.2.1.GA.

Since the latest log4j includes a trace level, there is no need to reference the custom jboss TRACE level in conf/jboss-log4j.xml configs, JBAS-4163.

There is additional information on trace level debugging in the articles Enabling TRACE logging on server and Using Logging.

Maven profiles are a pretty neat concept for organizing different settings for different builds.

Typically one sets them up in your settings.xml.  Projects will also have profiles in profiles.xml whose values you can override with your values in settings.xml.

A few observations I made about profiles.

1. Your profile is the conglomeration of all your active profiles in your settings.xml.
2. To activate other profile during a single maven execution, mvn -P profile1, profile2.

I always forget which level is which in Log4j so I copied this from the JavaDoc for the Level class.

Sometimes in a JSP/DSP page you will want to get the size of a collection and unless you are within a Range, ForEach or similar droplet you won’t have access to this value.

Struts has a nice solution (JSTL 1.1 will have a solution too) using the <bean:size> tag.

Here is an example of how to use Struts, DSPEL and JSTL to get the size of a collection.

  <dspel:getvalueof param="book.pages" var="pages"
                    vartype="java.util.Collection"/>
  <bean:size id="numPages" name="pages"/>
  Number of Pages: <c:out value="${numPages}"/>
  Number of Pages: <dspel:valueof value="${numPages}"/>

In a previous post, Shell Scripts with Windows LF’s Fail in Latest Cygwin, I wrote about how to use Perforce to check out all files in UNIX format. However if you use Eclipse then this solution will not work because Eclipse always inserts Windows LF’s in any line you insert into a file leading to a mess with files that have both UNIX and Windows LF’s.

However if you happen to use Maven to generate / copy your shell scripts to their target directories you can take advantage of the lineEnding property in the Assembly Director. If you specify the lineEnding property to be “unix” then the outputted shell scripts will be in UNIX format. For example:

<file>
  <source>src/main/scripts/foo.sh</source>
  <outputDirectory>bin</outputDirectory>
  <lineEnding>unix</lineEnding>
</file>

When I started Apache I saw these errors.

$ (OS 10048)Only one usage of each socket address (protocol/network address/port) is normally permitted.  : make_sock: could not bind to address 0.0.0.0:80
no listening sockets available, shutting down
Unable to open logs

This was puzzling to me since Apache was starting fine before. Fortunately on this forum thread, Failure Message starting Apache, one of the respondents had diagnosed the problem.

I’ve had the same problem. I noticed that when I reboot my computer (running XP pro), sometimes Apache worked. Then, I change the port to 3128 and it worked. But, then I was illuminated by God, and do a netstat -ao (-o displays the PID) and discover that Skype was listening in port 80 instead of apache -that is, I have both set up to run at startup, thus, if apache started first, it will have port 80 available, and Skype not, and vice-versa-. So my solution was to remove Skype from startup -I don’t use it too often- and make apache (and myself) happy by making port 80 available.

All I had to do was stop Skype and everything was fine. Too bad TcpView was not able to tell me that Skype was using port 80.

Eclipse was complaining in its Java Build Path panel that it did not know what MAVEN2_CLASSPATH_CONTAINER was. Searching around I realized that it was because I had not installed the Maven plugin.

After installing and restarting I went to Project > Update All Maven Dependencies to pull down all the dependencies.

Previously I talked about configuring a production Ruby on Rails applications using a Mongrel cluster with an Apache front end / load balancer. Now though a new Apache module was released called mod_rails which obviates the need for a Mongrel cluster. Seems promising, both for simplicity of installation and performance.