Eclipse, Maven & Jetty

How to run your web application Maven archetype with Jetty in Eclipse

We will be creating 2 'External Tool Configurations', one to start our web application and one to stop it.

To get started, we need need to bring up the Create, manage, and run configurations window. This can be done by clicking on

Run -> External Tools -> External Tools Configurations...

from the menu bar.

From here, we will context click on Program and choose to create a new configuration. Do this twice and give them the names mvn jetty run and mvn jetty stop.


Now we have to configure our new External Tool!

The configuration for both start and stop are very similar! The only difference is for the Arguments section.

Under Location, we need to enter the absolute path to our maven executable. On windows, this is mvn.bat and can be found in the \maven\bin\ directory. On *nix machines, you are looking for mvn.

For Working Directory, we enter ${project_loc}.

Finally, for Arguments, we enter clean jetty:run for our mvn jetty run configuration and jetty:stop for our mvn jetty stop configuration.


The next thing to configure is the Environment. Here we will set up MAVEN_OPTS so that we can remotely debug our application if the need ever arises! This is only done for the mvn jetty run configuration!

Basically, click on New... and give the variable the name MAVEN_OPTS with the value (all on one line):

-Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,address=4000,server=y,suspend=n


When we are done, it should look like so:

We are pretty much done. I like to have my configuration handy, so I usually add these external configurations to the favorites menu. This is done from the Common tab. Basically, you just add a check to the check box in the Display in favorites menu.

For the run configuration:

And finally, for the stop configuration:


That really is all there is to it. The only other thing to make sure of is that you have the maven-jetty-plugin added to your POM file.

Here is the plugin XML fragment that I have currently:

    <plugin>
       <groupId>org.mortbay.jetty</groupId>
       <artifactId>maven-jetty-plugin</artifactId>
       <version>6.1.16</version>
       <configuration>
           <stopPort>9966</stopPort>
           <stopKey>foo</stopKey>
       </configuration>
   </plugin>

Let me know if you have any questions!

Comparing XML Documents Semantically

I have been interested in comparing the contents of XML documents for some time now.

What I wanted to do is to perform a 'Diff' on 2 XML documents and determine whether or not they are the same document (regardless of whitespace or child element ordering).

In JAVA, I came across XmlUnit. This piece of software is excellent for determining whether or not 2 separate XML documents are equal.

In Perl, I came across XML-SemanticDiff. I thought it was great until I re-ordered the elements in one of my documents. Then this module wasn't so great anymore.

Since I really needed a piece of software equivalent to XmlUnit in Perl, I decided to create my own module and to call it XML-SemanticCompare. This new module really does perform a semantic diff on XML documents:

• Child element re-ordering doesn't result in false negatives.
• Whitespace is trimmed from text by default when comparing text and attribute values [can be turned off].
• Attributes can be ignored [turned off by default].

Using the module is extremely straightforward:

  use XML::SemanticCompare;
  my $x = XML::SemanticCompare->new;

  # compare 2 different files
  my $isSame = $x->compare($control_xml, $test_xml);
  # are they the same
  print "XML matches!\n"
    if $isSame;
  print "XML files are semantically different!\n"
    unless $isSame;

  # get the diffs
  my $diffs_arrayref = $x->diff($control_xml, $test_xml);

  # test xpath statement against XML
  my $success = $x->test_xpath($xpath, $test_xml);
  print "xpath success!\n" if $success;

The only downside to this piece of software is that it isn't very efficient (although, it isn't terribly inefficient either).

If you find yourself trying to compare XML documents DOM trees for equality and you are using Perl, please check out XML-SemanticCompare. If you can make the code more robust and efficient, please do!

A perl script to rename your files

For those of you looking for a cool way to rename your files, here is a little script that could work wonders for you.

Basically, this scripts takes in a PERL substitution expression and applies it to the filename of interest.

To get started, copy the script below into a file called 'rename.pl'. Once you have done that, then read the usage instructions by running the script with the '-h' option. Of course, you will need perl installed on your machine.

So why write this script? Because I got sick and tired of manually renaming files by hand. Some people have files called 'some_file.txt'. I prefer that file to be called 'SomeFile.txt'.

To accomplish this, all I have to do is run the script like so:

   perl rename.pl -u "s/_/ /g" some_file.txt

followed by

   perl rename.pl "s/ //g" "Some File.txt"

Note: The -u option causes the first letter of each word separated by a space to be capitalized.

Okay, maybe its quicker to manually do this for a single file, but if you are on Windows and have a whole folder full of files like that, then the process is:

   for %v in (*.txt) do perl rename.pl -u "s/_/ /g" "%v" 
   for %v in (*.txt) do perl rename.pl "s/ //g" "%v"

That is all there is to it! All of the files will be renamed with 'camel' text names.

Please make sure that before you attempt to batch rename files, that you have them backed up first!

Script start [hint: dont copy this line ;-)]

#!/usr/bin/perl -w

BEGIN {
 use Getopt::Std;
 use vars qw/ $opt_h $opt_u /;
 getopt;

 # usage
        sub usage {
  print STDOUT <<'END_OF_USAGE';

  Usage: rename [-hu] sub_regex [files]

                sub_regex is any expression that you would like to
                apply to filename. You can use capturing or just 
                matching.

                -h .... shows this message ;-)
                -u .... makes first letter of each word uppercase

  examples:

                1.
         perl rename.pl "s/_/ /g" rename_me.txt
                   This renames rename_me.txt to "rename me.txt"

                2.
         perl rename.pl -u "s/_/ /g" rename_me.txt
                   This renames rename_me.txt to "Rename Me.txt"

                3. MS Windows example
         for %v in (*.mp3) do perl rename.pl -u "s/_/ /g" "%v"
                   This renames all mp3 files in the current directory such that
                   every word begins with a capital letter and all underscores
                   are replaced with spaces.


END_OF_USAGE

}
 if ($opt_h) {
                usage();
  exit(0);
 }

}

# get the substition regex
$op = shift or (usage() and exit(1));

# go through file names
chomp(@ARGV) unless @ARGV;
for (@ARGV) {
    $was = $_;
    eval $op;
    die $@ if $@;
    # cap first letter of each word
    my $newname = "";
    my @components = split(/ /, $_);

    foreach (@components) {
      my $x = $_;
      $x = ucfirst lc $x if $opt_u;

      if ($newname eq "") {

         $newname = "$x";

      } else { 

         $newname .= " $x";

      }

    }

    rename($was,$newname) unless $was eq $newname;
}

Script End [hint: dont copy this line ;-)]

My Solaris .profile

I wanted to post my .profile file online because I have had to re-create it many times and I thought that others might find it useful!

Some of the things that the profile does are:

• colors the prompt
  
• adds shortcuts for ll and l (ls -lF and ls -laF)
• fixes the delete (among others) key so that delete actually deletes characters, rather than add tildes!
• adds mouse support to pico and makes 'nano' refer to pico (our system doesn't have nano)
  
• sets up CDPATH (adds the directories in this variable to the search path when using cd)

# set the term to xterm
export TERM=xterm

# Set up VISUAL, EDITOR for crontab editing
VISUAL=/usr/local/bin/pico
EDITOR=${VISUAL}

# Set up a prompt
PS1="\u@\h:\w# "
export PS1="\e[1;31m$(echo $PS1)\e[m"

# Export all the above
export VISUAL EDITOR PS1

# set up CDPATH
CDPATH=$HOME
export CDPATH

# set up some aliases
alias ll="ls -lF"
alias l="ls -laF"

alias nano="pico -w -m"
alias pico="/usr/local/bin/pico -w -m"


# fix some keys
case $TERM in
xterm*)
    bind '"\e[1~": beginning-of-line'
    bind '"\e[3~": delete-char'
    bind '"\e[4~": end-of-line'
    bind '"\177": backward-delete-char'
    ;;
esac
# eof

All that you need to do is save the above text in your home directory under the filename '.profile'.

I have tested this on Solaris, SuSe Linux and Ubuntu Linux.

Good luck!