Before going further, it’s important to understand some of the core concepts of Apache Ivy.
Apache Ivy Settings Files
Till now we have used default settings to carry out the tasks. Apache
Ivy allows to override the default settings through a settings file.
Apache Ivy setting file is an XML file, usually named as ivysettings.xml. In subsequent chapters, we use ivysettings.xml to
override the default settings.
Apache Ivy Pattern
Apache Ivy uses a concept called Pattern in many tasks and settings. Pattern is used to define a directory structure or the artifact file name. Ivy uses patterns to
to name artifacts.
to place artifacts in the proper directory.
to access or search artifacts in repositories.
Apache Ivy Pattern is composed of tokens which are replaced by actual values to evaluate a particular module or artifact. Token are surrounded by square brackets as [ext].
Table 5.1. Frequently used Tokens
| Token | Evaluates as |
|---|---|
| [organisation] | organisation name |
| [module] | module name |
| [revision] | revision name |
| [artifact] | artifact name (or id) |
| [type] | artifact type |
| [ext] | artifact file extension |
| [conf] | configuration name |
We may mix tokens, Ivy variables and actual directory names to compose a
pattern. For example, we wish to install or add module - Pigo developed
by xyz.com to our local repository. Module pigo Version 2.0 has three
artifacts - pigoapp class jar, pigoapp source jar and pigoapp javadoc
jar. If we set file pattern as
[module]-[artifact]-[type]-[revision].[ext], then Ivy will rename the
artifact files when they are placed into the cache. Tokens, their values
and filename for each of the artifact will be as follows.
Table 5.2. Token examples
| Artifact | Pattern [module]-[artifact]-[type]-[revision].[ext] becomes | File name (cache) |
|---|---|---|
| pigoapp classes jar file | [pigo]-[pigoapp]-[jar]-[2.0].[jar] | pigo-pigoapp-jar-2.0.jar |
| pigoapp source jar file | [pigo]-[pigoapp]-[source]-[2.0].[jar] | pigo-pigoapp-source-2.0.jar |
| pigoapp javadoc jar file | [pigo]-[pigoapp]-[doc]-[2.0].[jar] | pigo-pigoapp-doc-2.0.jar |
Note
For token [type] value changes depending on the type of artifact and for all other tokens, values are same for all three artifacts.
Apache Ivy Pattern to change the repository layout
Patterns are helpful to control the directory structure and artifact naming. Let’s go through some of the pattern examples which change the repository layout.
[organisation]/[module]/[type]s/[artifact]-[revision].[ext]
This pattern makes Ivy to
create a directory with organisation name.
then creates a subdirectory with module name.
then creates three subdirectories for 3 types – jar, source and doc. As there is a s after [type], the actual directory names will be jars, sources and docs.
then place the artifacts under the respective directories. File name consists of artifact name, revision and extension.
Resultant directory tree and files are shown in the next screenshot.
com.xyz/pigo/jars/pigoapp-1.1.jar
com.xyz/pigo/sources/pigoapp-1.1.jar
com.xyz/pigo/docs/pigoapp-1.1.jar
Let’s see what would be the layout with the next pattern
[organisation]/[module]/[artifact]-[type]-[revision].[ext]
This pattern lands all artifacts in the same directory and artifact file name ends up with the types. Layout and file names are shown in the next screenshot.
com.xyz/pigo/pigoapp-jar-1.1.jar
com.xyz/pigo/pigoapp-source-1.1.jar
com.xyz/pigo/pigoapp-doc-1.1.jar
Apache Ivy Pattern to rename the artifacts in Retrieval Task
In the previous chapter, for <ivy:retrieve> we used following pattern
myfolder/[artifact]-[revision].[ext]
This pattern makes Ivy to
to retrieve required artifacts and rename the artifacts with artifact name, revision and ext.
then copy the artifact to myfolder.
myfolder/pigoapp-1.1.jar
myfolder/pigoapp-1.1.jar
myfolder/pigo/pigoapp-1.1.jar
To sum up, Apache Ivy uses Pattern setting to
to name or rename artifacts.
to change the repository or directory layouts.
to place artifacts in the proper directory.
to access, search or retrieve artifacts from different repositories layouts.