Writing Installation XML Files

What You Need

Your editor

In order to write your XML installation files, you just need a plain text editor. Of course it's always easier to work with color coded text, so you might rather want to work with a text editor having such a feature. Here is a list of free editors that work well :

• Jext : http://www.jext.org/
• JEdit : http://www.jedit.org/
• classics like Vim and (X)Emacs.

Writing XML

Though you might not know much about XML, you have certainly heard about it. If you know XML you can skip this subsection as we will briefly present how to use XML.

XML is a markup language, really close to HTML. If you've ever worked with HTML the transition will be fast. However there are a few little things to know. The markups used in XML have the following form : <markup>. Each markup has to be closed somewhere with its ending tag : </markup>. Each tag can contain text and other markups. If a markup does not contain anything, it is just reported once : <markup/>. A markup can contain attributes like : <markup attr1="123" attr2="hello !"/>. Here is a sample of a valid XML structure :

<chapter title="Chapter 1">
  <section name="Introduction">
    <paragraph>
    This is the text of the paragraph number 1. It is available for the very low
    price of <price currency="dollar">1 000 000</price>.
    </paragraph>
  </section>
  <section name="xxx">
  xxx
  </section>
</chapter>

You should be aware of the following common mistakes :

• markups are case sensitive : <markup> is different from <Markup>.

• you must close the markups in the same order as you create them : <m1><m2>(...)</m2></m1> is right but <m1><m2>(...)</m1></m2> is not.

Also, an XML file must start with the following header :
<?xml version="1.0" encoding="iso-8859-1 standalone="yes" ?>. The only thing you should modify is the encoding (put here the one your text editor saves your files to). The standalone attribute is not very important for us.

This (brief !) introduction to XML was just meant to enable you to write your installation specification. For a better introduction there are plenty of books and articles/tutorials dealing with XML on the Internet, in book stores, in magazines and so on.

Variable Substitution

During the installation process IzPack can substitute variables in various places with real values. Obvious targets for variable substitution are resource files and launch scripts, however you will notice many more places where it is more powerful to use variables rather then hard coded values. Wherever variables can be used it will be explained in the documentation.

There are three types of variables:

• Built-In variables. These are implemented in IzPack and are all dynamic in nature. This means that the value of each variable depends on local conditions on the target system.
• Environment variables. These are provided by the operating system the installer is run on.
• Variables that you can define. You also define the value, which is fixed for a given installation file.

You define your own variables in the installation XML file with the <variable> tag. How to do this is explained in detail later in this chapter.

Please note that when using variables they must always appear with a '$' sign as the first character, even though they are not defined this way.

The Built-In Variables

The following variables are built-in :

• $INSTALL_PATH : the installation path on the target system, as chosen by the user
• $JAVA_HOME : the Java^TM virtual machine home path
• $USER_HOME : the user's home directory path
• $USER_NAME : the user name
• $APP_NAME : the application name
• $APP_URL : the application URL
• $APP_VER : the application version
• $ISO3_LANG : the ISO3 language code of the selected langpack.
• $FILE_SEPARATOR : the file separator on the installation system

Environment Variables

Environment variables can be accessed via the syntax ${ENV[variable]}. The curly braces are mandatory. Note that variable names are case-sensitive and usually in UPPER CASE.

Example: To get the value of the OS environment variable "CATALINA_HOME", use ${ENV[CATALINA_HOME]}.

Parse Types

Parse types apply only when replacing variables in text files. At places where it might be necessary to specify a parse type, the documentation will mention this. Depending on the parse type, IzPack will handle special cases -such as escaping control characters- correctly. The following parse types are available:

• plain - use this type for plain text files, where no special substitution rules apply. All variables will be replaced with their respective values as is.
• javaprop - use this type if the substitution happens in a Java properties file. Individual variables might be modified to function properly within the context of Java property files.
• xml - use this type if the substitution happens in a XML file. Individual variables might be modified to function properly within the context of XML files.
• shell - use this type if the substitution happens in a shell script. Because shell scripts use $variable themselves, an alternative variable marker is used: %variable or %{variable}.

The IZPACK Elements

When writing your installer XML files, it's a good idea to have a look at the IZPACK installation DTD.

The Root Element <installation>

The root element of an installation is <installation>. It takes one required attribute : version. The attribute defines the version of the XML file layout and is used by the compiler to identify if it is compatible with the XML file. This should be set to $1.0$ for the moment.

The Information Element <info>

This element is used to specify some general information for the installer. It contains the following elements :

• <appname> : the application name
• <appversion> : the application version
• <appsubpath> : the subpath for the default of the installation path. A variable substitution and a maskable slash-backslash conversion will be done. If this tag is not defined, the application name will be used instead.
• <url> : the application official website url
• <authors> : specifies the author(s) of the application. It must contain at least one <author> element whose attributes are :
  • name : the author's name
  • email : the author's email
• <uninstaller> : specifies whether to create an uninstaller after installation, it has only the write attribute, with default value yes. If this tag is not specified, the uninstaller will still be written.
• <javaversion> : specifies the minimum version of Java required to install your program. Values can be 1.2, 1.2.2, 1.4, etc. The test is a lexical comparison against the java.version System property on the install machine.
• <webdir> : Causes a ``web installer'' to be created, and specifies the URL packages are retrieved from at install time. The content of the tag must be a properly formed URL. See section 3.6 for more details.

Here is an example of a typical <info> section :

<info>
  <appname>Super extractor</appname>
  <appversion>2.1 beta 6</appversion>
  <appsubpath>myCompany/SExtractor</appsubpath>
  <url>http://www.superextractor.com/</url>
  <authors>
    <author name="John John Doo" email="jjd@jjd-mail.com"/>
    <author name="El Goyo" email="goyoman@mymail.org"/>
  </authors>
  <javaversion>1.2</javaversion>
</info>

The Variables Element <variables>

This element allows you to define variables for the variables substitution system. Some variables are built-in, such as $INSTALL_PATH (which is the installation path chosen by the user). When you define a set of variables, you just have to place as many <variable> tags in the file as needed. If you define a variable named VERSION you need to type $VERSION in the files to parse. The variable substitutor will then replace it with the correct value. One <variable> tag take the following attributes :

• name : the variable name
• value : the variable value

Here's a sample <variables> section :

<variables>
  <variable name="app-version" value="1.4"/>
  <variable name="released-on" value="08/03/2002"/>
</variables>

The GUI Preferences Element <guiprefs>

This element allows you to set the behavior of your installer GUI. This information will not have any effect on the command-line installers that will be available in future versions of IZPACK . The arguments to specify are :

• resizable : takes yes or no and indicates whether the window size can be changed or not.
• width : sets the initial window width
• height : sets the initial window height.

Here's a sample :

<guiprefs resizable="no" width="800" height="600"/>

Starting from IzPack 3.6, the look and feel can be specified in this section on a per-OS basis. For instance you can use the native look and feels on Win32 and OS X but use a third-party one on Unix-like platforms. To do that, you have to add some children to the guiprefs tag:

• laf: the tag that specifies a look and feel. It has a name parameter that defines the look and feel name.
• Each laf element needs at least one os tag, specified like in the other parts of the specification that support this tag.
• Like you can add os elements, you can add any number of param elements to customize a look and feel. A param elements has two attribues: name and value.

The available look and feels are:

• Kunststoff: kunststoff
• Liquid: liquid
• Metouia: metouia
• JGoodies Looks: looks

If you don't specify a look and feel for a particular operating system, then the default native one will be used: Windows on Windows, Aqua on Mac OS X and Metal on the Unix-like variants.

The Liquid Look and Feel supports the following parameters:

• decorate.frames: yes means that it will render the frames in Liquid style
• decorate.dialogs: yes means that it will render the dialogs in Liquid style

The JGoodies Looks look and feel can be specified by using the variant parameters. The values can be one of:

• extwin: use the Windows Extension look
• plastic: use the basic Plastic look
• plastic3D: use the Plastic 3D look
• plasticXP: use the Plastic XP look (default).

Here is a small sample:

<guiprefs height="600" resizable="yes" width="800">
    <laf name="metouia">
        <os family="unix" />
    </laf>
    <laf name="looks">
        <os family="windows" />
        <param name="variant" value="extwin" />
    </laf>
</guiprefs>

Starting from IzPack 3.7, some characteristics can be customized with the <modifier> tag which contains following attributes:

• key: a well defined key of the characteristic which should be changed.
• value the value for the key.

Following key value pairs are defined:

• useButtonIcons: possible are "yes" or "no". Default is "yes". If it is set to "no", all buttons which are created via the ButtonFactory contains no icon also a icon id was submitted. Directly created buttons are not affected.
• useLabelIcons: possible are "yes" or "no". Default is "yes". If it is set to "no", all labels which are created via the LabelFactory contains no icon also a icon id was submitted. Directly created labels are not affected.

The Localization Element <locale>

This element is used to specify the language packs (langpacks) that you want to use for your installer. You must set one <langpack> markup per language. This markup takes the iso3 parameter which specifies the iso3 language code.

Here's a sample :

<locale>
  <langpack iso3="eng"/>
  <langpack iso3="fra"/>
  <langpack iso3="spa"/>
</locale>

The supported ISO3 codes are :

ISO3 code	Language
cat	Catalunyan
chn	Chinese
cze	Czech
dan	Danish
deu	German
eng	English
fin	Finnish
fra	French
hun	Hungarian
ita	Italian
jpn	Japanese
mys	Malaysian
ned	Nederlands
nor	Norwegian
pol	Polnish
por	Portuguese (Brazilian)
rom	Romanian
rus	Russian
scg	Serbian
spa	Spanish
svk	Slovakian
swe	Swedish
ukr	Ukrainian

The Resources Element <resources>

Several panels, such as the license panel and the shortcut panel, require additional data to perform their task. This data is supplied in the form of resources. This section describes how to specify them. Take a look at each panel description to see if it might need any resources. Currently, no checks are made to ensure resources needed by any panel have been included. The <resources> element is not required, and no <res> elements are required within.

You have to set one <res> markup for each resource. Here are the attributes to specify :

• src : the path to the resource file which can be named freely of course (for instance my-picture.jpg).
• id : the resource id, depending on the needs of a particular panel
• parse : takes yes or no (default is no) - used to specify whether the resource must be parsed at the installer compilation time. For instance you could set the application version in a readme file used by InfoPanel.
• type : specifies the parse type. This makes sense only for a text resource - the default is plain, other values are javaprop, xml (Java properties file and XML files)
• encoding : specifies the resource encoding if the receiver needs to know. This makes sense only for a text resource.

Here's a sample :

<resources>
  <res id="InfoPanel.info" src="doc/readme.txt" parse="yes"/>
  <res id="LicencePanel.licence" src="legal/License.txt"/>
</resources>

The Panels Element <panels>

Here you tell the compiler which panels you want to use. They will appear in the installer in the order in which they are listed in your XML installation file. Take a look at the different panels in order to find the ones you need. The <panel> markup takes a single attribute classname which is the classname of the panel.

Here's a sample :

<panels>
  <panel classname="HelloPanel"/>
  <panel classname="LicencePanel"/>
  <panel classname="TargetPanel"/>
  <panel classname="InstallPanel"/>
  <panel classname="FinishPanel"/>
</panels>

The Packs Element <packs>

This is a crucial section as it is used to specify the files that need to be installed. The <packs> section consists of several <pack> tags.

The <pack> takes the following attributes :

• name: the pack name
• required: takes yes or no and specifies whether the pack is optional or not.
• os: optional attribute that lets you make the pack targeted to a specific operating system, for instance unix, mac and so on.
• preselected: optional attribute that lets you choose whether the pack is by default selected for installation or not. Possible values are yes and no. A pack which is not preselected needs to be explicitly selected by the user during installation to get installed.
• loose: can be used so that the files are not located in the installer Jar. The possible values are true or false, the default beeing false. The author of this feature needed to put his application on a CD so that the users could run it directly from this media. However, he also wanted to offer them the possibility to install the software localy. Enabling this feature will make IzPack take the files on disk instead of from the installer. Please make sure that your relative files paths are correct !
• id: this attribute is used to give a unique id to the pack to be used for internationalization.

Internationalization of the PacksPanel

In order to provide internationalization for the PacksPanel, so that your users can be presented with a different name and description for each language you support, you have to create a file named packsLang.xml_xyz where xyz is the ISO3 code of the language in lowercase. Please be aware that case is significant. This file has to be inserted in the resources section of install.xml with the id and src attributes set at the name of the file. The format of these files is identical with the distribution langpack files located at $IZPACK_HOME/install/langpacks/installer. For the name of the panel you just use the pack id as the txt id. For the description you use the pack id suffixed with '.description'.

The following sections describe the tags available for a <pack> section.

<description> - pack description

The contents of the <description> tag describe the pack contents. This description is displayed if the user highlights the pack during installation.

<depends> - pack dependencies

This can be used to make this pack selectable only to be installed only if some other is selected to be installed. The pack can depend on more than one by specifying more than one <depends> elements.
Circular depedencies are not supported and the compiler reports an error if one occurs.

This tag takes the following attribute:

• packname: The name of the pack that it depends on

<os> - OS restrictions

It is possible to restrict a panel to a certain list of operating systems. This tag takes the following attributes:

• family: unix, windows or mac
• name: the exact OS name (ie Windows, Linux, ...)
• version: the exact OS version (see the JVM os.version property)
• arch: the machine architecture (see the JVM os.arch property).

<updatecheck>

This feature can update an already installed package, therefore removing superfluous files after installation. Here's how this feature author (Tino Schwarze) described it on the IzPack development mailing-list:

Each pack can now specify an <updatecheck> tag. It supports a subset of ant fileset syntax, e.g.:

<updatecheck>
  <include name="lib/**" />
  <exclude name="config/local/** />
</updatecheck>

If the paths are relative, they will be matched relative to $INSTALL_PATH. Update checks are only enabled if at least one <include> is specified. See com.izforge.izpack.installer.Unpacker for details.

<file> - add files or directories

The <file> tag specifies a file (a directory is a file too) to include into the pack. It takes the following attributes:

• src: the file location (relative path) - if this is a directory its content will be added recursively

• targetdir: the destination directory, could be something like $INSTALL_PATH/subdirX

• os: can optionally specify a target operating system (unix, windows, mac) - this means that the file will only be installed on its target operating system

• override: if true then if the file is already installed, it will be overwritten. Alternative values: asktrue and askfalse - ask the user what to do and supply default value for non-interactive use. Another possible values is update. It means that the new file is only installed if it's modification time is newer than the modification time of the already existing file (note that this is not a reliable mechanism for updates - you cannot detect whether a file was altered after installation this way.) By default it is set to update.

<additionaldata>

This tag can also be specified in order to pass additional data related to a file tag for customizing.

• <key>: key to identify the data
• <value>: value which can be used by a custom action

<singlefile> - add a single file

Specifies a single file to include. The difference to <file> is that this tag allows the file to be renamed, therefore it has a target attribute instead of targetdir.

• src: the file location (relative path)

• target: the destination file name, could be something like $INSTALL_PATH/subdirX/fileY

• os: can optionally specify a target operating system (unix, windows, mac) - this means that the file will only be installed on its target operating system

• override: see <file> (2.3.8) for description

A <additionaldata> (2.3.8) tag can also be specified for customizing.

<fileset>: add a fileset

The <fileset> tag allows files to be specified using the powerful Jakarta Ant set syntax. It takes the following parameters:

• dir: the base directory for the fileset (relative path)

• targetdir: the destination path, works like for <file>

• casesensitive: optionally lets you specify if the names are case-sensitive or not - takes yes or no

• defaultexcludes: optionally lets you specify if the default excludes will be used - takes yes or no.

• os: specifies the operating system, works like for <file>

• override: see <file> for description

• includes: comma- or space-separated list of patterns of files that must be included; all files are included when omitted. This is an alternative for multiple include tags.

• excludes: comma- or space-separated list of patterns of files that must be excluded; no files (except default excludes) are excluded when omitted. This is an alternative for multiple exclude tags.

You specify the files with <include> and <exclude> tags that take the name parameter to specify the Ant-like pattern :

• ** : means any subdirectory
• * : used as a wildcard.

Here are some examples of Ant patterns :

• <include name="lib"/> : will include lib and the subdirectories of lib

• <exclude name="**/*.java"/> : will exclude any file in any directory starting from the base path ending by .java

• <include name="lib/*.jar"/> : will include all the files ending by .jar in lib

• <exclude name="lib/**/*FOO*"/> : will exclude any file in any subdirectory starting from lib whose name contains FOO.

There area set of definitions that are excluded by default file-sets, just as in Ant. IzPack defaults to the Ant list of default excludes. There is currently no equivalent to the <defaultexcludes> task. Default excludes are:

     **/*\~{}
     **/\#*\#
     **/.\#*
     **/%*%
     **/.\_*
     **/CVS
     **/CVS/**
     **/.cvsignore
     **/SCCS
     **/SCCS/**
     **/vssver.scc
     **/.svn
     **/.svn/**
     **/.DS\_Store

A <additionaldata> (2.3.8) tag can also be specified for customizing.

<parsable> - parse a file after installation

Files specified by <parsable> are parsed after installation and may have variables substituted.

• targetfile : the file to parse, could be something like
  $INSTALL_PATH/bin/launch-script.sh
  A slash will be changed to the system dependant path separator (e.g. to a backslash on Windows) only if no backslash masks the slash.

• type : specifies the type (same as for the resources) - the default is plain

• encoding : specifies the file encoding

• os: specifies the operating system, works like for <file>

<executable> - mark file executable or execute it

The <executable> tag is a very useful thing if you need to execute something during the installation process. It can also be used to set the executable flag on Unix-like systems. Here are the attributes :

• targetfile : the file to run, could be something like
  $INSTALL_PATH/bin/launch-script.sh
  Slashes are handled special (see attribute targetfile of tag <parsable>2.3.8).

• class : If the executable is a jar file, this is the class to run for a Java^TM program

• type : bin or jar (the default is bin)

• stage : specifies when to launch : postinstall is just after the installation is done and the default value, never will never launch it (useful to set the +x flag on Unix). uninstall will launch the executable when the application is uninstalled. The executable is executed before any files are deleted.

• failure : specifies what to do when an error occurs : abort will abort the installation process, ask (default) will ask the user what to do and warn will just tell the user that something is wrong

• os: specifies the operating system, works like for <file>

• keep : specifies whether the file will be kept after execution. The default is to delete the file after is has been executed. This can be changed by specifying keep="true".

A <args> tag can also be specified in order to pass arguments to the executable:

• <arg>: passes the argument specified in the value attribute. Slashes are handled special (see attribute targetfile of tag <parsable>2.3.8).

<os> - make a file OS-dependent

The <os> tag can be used inside the <file>, <fileset>, <singlefile>, <parsable>, <executable> tags to restrict it's effect to a specific operating system family, architecture or version:

• family: unix, windows, mac to specify the operating system family
• name: the operating system name
• version: the operating system version
• arch: the operating system architecture (for instance the Linux kernel can run on i386, sparc, and so on)

Here's an example installation file :

<packs>
    <!-- The core files -->
    <pack name="Core" required="yes">
        <description>The IzPack core files.</description>
        <file targetdir="$INSTALL_PATH" src="bin"/>
        <file targetdir="$INSTALL_PATH" src="lib"/>
        <file targetdir="$INSTALL_PATH" src="legal"/>
        <file targetdir="$INSTALL_PATH" src="Readme.txt"/>
        <file targetdir="$INSTALL_PATH" src="Versions.txt"/>
        <file targetdir="$INSTALL_PATH" src="Thanks.txt"/>
        <parsable targetfile="$INSTALL_PATH/bin/izpack-fe"/>
        <parsable targetfile="$INSTALL_PATH/bin/izpack-fe.bat"/>
        <parsable targetfile="$INSTALL_PATH/bin/compile"/>
        <parsable targetfile="$INSTALL_PATH/bin/compile.bat"/>
        <executable targetfile="$INSTALL_PATH/bin/compile" stage="never"/>
        <executable targetfile="$INSTALL_PATH/bin/izpack-fe" stage="never"/>
    </pack>

    <!-- The documentation (1 directory) -->
    <pack name="Documentation" required="no">
        <description>The IzPack documentation (HTML and PDF).</description>
        <file targetdir="$INSTALL_PATH" src="doc"/>
    </pack>
</packs>

The Native Element <native>

Use this if you want to use a feature that requires a native library. The native libraries are placed under bin/native/... There are 2 kinds of native libraries : the IZPACK libraries and the third-party ones. The IzPack libraries are located at bin/native/izpack, you can place your own libraries at bin/native/3rdparty. It is possible to place a native library also into the uninstaller. It is useable from CustomActions (7). If one or more are referenced for it, the needed support classes are automatically placed into the uninstaller. To place it only on operating systems for which they are build, it is possible to define an OS restriction. This restriction will only be performed for the uninstaller. The markup takes the following attributes :

• type : izpack or 3rdparty
• name : the library filename
• stage: stage where to use the library (install|uninstall|both)

<os> - make a library OS-dependent

The <os> tag can be used to restrict the inclusion into the uninstaller to a specific operating system family, architecture or version. The inclusion into the installer will be always done. For more information see 2.3.8.

Here's a sample :

<native type="izpack" name="ShellLink.dll"/>

The Jar Merging Element <jar>

If you adapt IZPACK for your own needs, you might need to merge the content of another jar file into the jar installer. For instance, this could be a library that you need to merge. The <jar> markup allows you to merge the raw content of another jar file into the installer and the uninstaller. It is necessary that the paths in the jars are unique because only the contained files of the jar are added to the installer jar, not the jar file self. The attributes are:

• src : the path at compile time
• stage: stage where to use the contents of the additional jar file (install|uninstall|both)

A sample :

<jar src="../nicelibrary.jar"/>

The Available Panels

In this section I will introduce the various panels available in IzPack. The usage for most is pretty simple and described right here. The more elaborate ones are explained in more detail in the Advanced Features chapter or in their own chapter. The panels are listed by their class name. This is the name that must be used with the classname attribute (case-sensitive).

HelloPanel

This panel welcomes the user by displaying the project name, the version, the URL as well as the authors.

InfoPanel and HTMLInfoPanel

This is a kind of 'README' panel. It presents text of any length. The text is specified by the (HTML)InfoPanel.info resource. Starting from IzPack 3.7.0, variables substitution is allowed.

LicencePanel and HTMLLicencePanel

Note : there is a mistake in the name - it should be LicensePanel. In France the word is Licence ... and one of my diploma is a 'Licence' so ... :-)

These panels can prompt the user to acknowledge a license agreement. They block unless the user selects the 'agree' option. To specify the license agreement text you have to use the (HTML)LicencePanel.licence resource.

PacksPanel

Allows the user to select the packs he wants to install.

ImgPacksPanel

This is the same as above, but for each panel a different picture is shown to the user. The pictures are specified with the resources ImgPacksPanel.img.x where x stands for the pack number, the numbers start from 0. Of course it's up to you to specify as many images as needed and with correct numbers. For instance if you have 2 packs core and documentation (in this order), then the resource for core will be ImgPacksPanel.img.0 and the resource for doc will be ImgPacksPanel.img.1. The supported image formats depend on what you JVM supports, but starting from J2SE 1.3, GIF, JPEG and PNG are supported.

TargetPanel

This panel allows the user to select the installation path. It can be customized with the following resources (they are text files containing the path) :

• TargetPanel.dir.f where f stands for the family (mac, macosx, windows, unix)
• TargetPanel.dir : the directory name, instead of the software to install name
• TargetPanel.dir.d where d is a "dynamic" name, as returned by the Java^TM virtual machine. You should write the name in lowercase and replace the spaces with underscores. For instance, you might want a different setting for Solaris and GNU/Linux which are both Unix-like systems. The resources would be TargetPanel.dir.sunos, TargetPanel.dir.linux. You should have a Unix-resource in case it wouldn't work though.

InstallPanel

You should always have this one as it launches the installation process !

XInfoPanel

A panel showing text parsed by the variable substitutor. The text can be specified through the XInfoPanel.info resource. This panel can be useful when you have to show information after the installation process is completed (for instance if the text contains the target path).

FinishPanel

A ending panel, able to write automated installer information. For details see the chapter on 'Advanced Features'.

SimpleFinishPanel

Same as FinishPanel, but without the automated installer features. It is aimed at making the life easier for end-users who will never encounter the automated installer extra feature.

ShortcutPanel

This panel is used to create desktop shortcuts. For details on using the ShortcutPanel see the chapter 'Desktop Shortcuts'.

UserInputPanel

This panel allows you to prompt the user for data. What the user is prompted for is specified using an XML file which is included as a resource to the installer. See chapter 6 on page for a detailed explanation.

CompilePanel

This panel allows you to compile just installed Java sourcecode. The details for the compilation are specified using the resource CompilePanel.Spec.xml. The XML file has the following format:

<compilation>
  <global>
    <compiler>
      <choice value="$JAVA_HOME/bin/javac" />
      <choice value="jikes" />
    </compiler>
    <arguments>
      <choice value="-O -g:none" />
      <choice value="-O" />
      <choice value="-g" />
      <choice value="" />
    </arguments>
  </global>
  <jobs>
    <classpath add="$INSTALL_PATH/src/classes/" />
    <job name="optional name">
      <directory name="$INSTALL_PATH/src/classes/xyz" />
    </job>
    <job name="another job">
      <packdepency name="some package name" />
      <classpath sub="$INSTALL_PATH/" />
      <directory name="$INSTALL_PATH/src/classes/abc" />
      <file name="$INSTALL_PATH/some/file.java" />
    </job>
  </jobs>
</compilation>

In theory, jobs can be nested but this has not been tested at all. A change to the classpath within a job only affects this job and nested jobs. The classpath should be specified before any files or directories.

The user can change the compiler to use and choose from some default compilation options before compilation is started.

ProcessPanel

This panel allows you to execute arbitrary files after installation. The details for the compilation are specified using the resource ProcessPanel.Spec.xml.

The XML file has the following format:

<processing>
  <job name="do xyz">
    <os family="windows" />
    <executefile name="$INSTALL_PATH/scripts/xyz.bat">
      <arg>doit</arg><arg>$variable</arg>
    </executefile>
  </job>
  <job name="do xyz">
    <os family="unix" />
    <executefile name="$INSTALL_PATH/scripts/xyz.sh">
      <arg>doit</arg><arg>$variable</arg>
    </executefile>
  </job>
</processing>

Each job may have an <os> attribute - see 2.3.8 for details.

It is also possible to execute Java classes from this panel. Here's what this feature author (Alex Bradley) says:

I've been able to work around my requirements by extending the ProcessPanelWorker functionality to run user-specified classes. I've extended the DTD of the ProcessPanel.Spec.xml to include a new element:

<executeclass name="classname">
<args..../>
</executeclass>

I've also added a new sub-class of Processable called executeclass. This will run a user-specified class in the context of the installer JVM with a single method :

run( AbstractUIProcessHandler handler, String[] args]);

It can do everything I need and more. In particular, it allows me to write a process extension and still be able to provide feedback to the user through the feedback panel, and to add new functionality to the installer, after its been built.

New with version 3.7 is the possibility to tee output that is written to the ProcessPanel's textarea into an optional logfile. Using this feature is pretty much straightforward, you only have to add a line in ProcessPanel.Spec.xml that will tell IzPack the location, where the logfile should be stored.

Variable substitution is performed, so you can use $INSTALL_PATH as example.

The name of the logfile is not (yet) configurable but should fit in most cases. It will be named

Install_V<$APP_VER>_<YYYY>-<MM>-<DD>_<hh>-<mm>-<ss>_<RandomId>.log

Here's an example:

<processing>
  <logfiledir>$INSTALL_PATH</logfiledir>
  <job name="do xyz">
    <os family="windows" />
    <executefile name="$INSTALL_PATH/scripts/xyz.bat">
      <arg>doit</arg><arg>$variable</arg>
    </executefile>
</processing>

This will generate a logfile named e.g. Install_V1.3_2004-11-08_19-22-20_43423.log located in $INSTALL_PATH.

ProcessPanelWorker will write all output that is directed to stdout and stderr to this file if ProcessPanel.Spec.xml contains the logfiledir entry.

Please note that this one file is used for storing the complete output of all jobs and not a file for each job that is run.

JDKPathPanel

This panel allows the user to select a JDK path. The variable JAVA_HOME does not point to a JDK, else to a JRE also the environment variable points to a JDK. This is not a bug, this is the behavior of the VM. But some products needs a JDK, for that this panel can be used. There is not only a selection of the path else a validation. The validation will be done with the file JDKPath/lib/tools.jar. If JAVA_HOME points to the VM which is placed in the JDK, the directory will be used as default (JAVA_HOME/..). If there is the variable

JDKPathPanel.skipIfValid

defined with the value "yes", the panel will be skiped if the path is valid. Additional it is possible to make a version control. If one or both variables

JDKPathPanel.minVersion
JDKPathPanel.maxVersion

are defined, only a JDK will be accepted which has a version in the range of it. The detection is a little bit pragmatically, therefor it is possible, that the detection can fail at some VMs. The values in the install.xml should be like

<variables>
  <variable name="JDKPathPanel.minVersion" value="1.4.1" />
  <variable name="JDKPathPanel.maxVersion" value="1.4.99" />
  <variable name="JDKPathPanel.skipIfValid" value="yes" />
</variables>

If all is valid, the panels isValidated method sets the variable

JDKPath

to the chosen path. Be aware, this variable exist not until the JDKPanel was quitted once. At a secound activation, the default will be the last selection.