# Custom Code and Patch Compatibility¶

Subscribers

If you deploy code that customizes or patches your DXP 7.2 installation, you must maintain its compatibility with all patches you’re using. The following topics explain how to do this.

Important

These customization and patching instructions apply to Liferay DXP 7.2 only. They do not apply to DXP 7.3+.

## Storing Patch Level Information for Custom Patches¶

The Patching Tool’s store and diff commands work with differences between patches, including Liferay DXP patches and custom DXP patches. The store command writes a patch level file for the patch source code. The diff command prints the differences between patches.

The ./patching-tool.sh store command manages patching level information used by the diff command. Your patches must contain source code to store a patch level and to prepare usable information for the diff command. Here are the store command options:

• add: Stores the patch level to the patches folder.

• info: Prints the list of patches which make up the stored patch level.

• rm: Removes previously stored patch level information.

• update: Adds or updates patch level information.

For detailed usage information, run ./patching-tool.sh help store.

## Comparing Patch Level Differences¶

The ./patching-tool.sh diff command prints the differences between two patch levels. At least one stored patch level must be available. This command accepts options for filtering the output:

• collisions: Lists modified files that collide with deployed plugins.

• files: Lists the modified files.

• fixed-issues: Lists the LPS/LPE issues (from the issue tracking system) that the patch fixes.

• html: Specify this along with one of the filtering options (source, files, or fixed-issues) and after the patch levels, to write the differences to an HTML file (<stored-name-1>-<stored-name-2>-[type]-diff.html) in the diffs folder. Additions are colored green and deletions are colored red.

• source: Shows the source code differences between the two patch levels.

For detailed usage information, run ./patching-tool.sh help diff.

## Handling Collisions Between Patches and Custom Plugins¶

Some patches update files you might have customized via a plugin. The list-collisions command returns JSP file differences (collisions) in OSGi fragment bundles:

./patching-tool.sh list-collisions


It is an alias for the following diff command:

./patching-tool.sh diff collisions files _base


The _base argument is the literal patch level name. Collisions only appear for installed patches that contain source code files.

If you removed certain patches or there is a collision of some kind use the -force argument to force the Patching Tool to install the currently available patches no matter what.

Example:

./patching-tool.sh profile_name install -force


Now you know how to integrate your custom code and custom patches with other DXP patches.