The Empty Condition
The Empty Condition can be used to check whether an object given by a nested parameter is empty. Objects can be plain strings, variables, files or directories.
Example:
<condition type="empty" id="isEmptyImportDir"> <dir>${INSTALL_PATH}/import</dir> </condition>
The Empty condition has been introduced in IzPack 5.0.
Nested Elements
The nested elements of the Empty condition don't have any further attributes, but receive contents in the text embedded. IzPack variables are dynamically resolved for each value.
string
Used when a string is to be checked whether it is empty.
variable
The variable name when a variable value is to be checked whether it is empty.
This is not the same as checking if a variable exists, which can be checked by the Exists condition.
file
The file name when the contents of a file are to be checked to be empty.
This is not the same as checking if a file exists, which can be checked by the Exists condition.
dir
The directory name when a directory has to be checked to contain no files.
This is not the same as checking if a directory exists, which can be checked by the Exists condition.