Installer Requirements
Installer Requirements - <installerrequirements>
The <installerrequirements> element is used to ensure prerequisites for the installation. The installation is stopped with the message of the first requirement with a failing or undefined condition. In contrast to Dynamic Installer Requirements the requirements are checked only once at start of the installer.
Common Example
<installerrequirements>
<installerrequirement condition="izpack.linuxinstall"
message="This installer runs on linux only!" />
<installerrequirement condition="isUpgrade"
message="not.an.upgrade.message" />
...
</installerrequirements>The <installerrequirements> are checked after computation of dynamic variables and conditions but before executing the first panel. So you can refer not only to built-in conditions but also to custom conditions, which may depend on external files for example. But you cannot depend on the result of a panel (e.g. Target Panel).
<installerrequirement> - Attributes
Attribute | Description | Default | Required |
|---|---|---|---|
| A valid condition ID defined within the <conditions/> element. | none | yes |
| A valid message ID from the appropriate translation file. If it can't be found the mentioned ID itself is displayed instead of the translated text. | none | yes |
Please note that the definition of a <installerrequirement> here is different from the identical named child of <dynamicinstallerrequirements>.
See also
<info> may contain several requirements:
<expiresdate> - Installer Expiration after a certain date
<javaversion> - Minimum Java version for running installer
<requiresjdk> – A JDK is needed for installation and application