Page Comparison

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• plain values
• environment variables
• system properties
• INI files
• option/property files (key-value pairs)
• XML files (using XPath-like queries)
• INI/option/XML files from within an ZIP or JAR file
• Windows registry
• output of a command execution

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The above example is functionally equivalent to

<variables><dynamicvariables>
    <variable name="search.path" value="${ENV[PATH]}"/>
</variable>dynamicvariable>

since there are no replacements used which might be refreshed on a panel change and the environment variable PATH won't change during the runtime of an installation process.

Values from System Properties

Using a  dynamic variable assignment from an system property is recognized by using the value ${SYSTEM[property]} in the variable definition. For example the following definition will give you the java.io.tmpdir:

<dynamicvariables>
    <variable name="tmpdir" value="${SYSTEM[java.io.tmpdir]}"/>
</dynamicvariable>

Values from Property/Option Files

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