[CAMEL-20664] camel-mapstruct - MapStruct mappers not found in Spring Boot

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Information Provided
• Affects Version/s: 4.0.0
• Fix Version/s: 4.4.0
• Component/s: camel-mapstruct

Environment

$ java -version
openjdk version "17.0.7" 2023-04-18
OpenJDK Runtime Environment Temurin-17.0.7+7 (build 17.0.7+7)
OpenJDK 64-Bit Server VM Temurin-17.0.7+7 (build 17.0.7+7, mixed mode, sharing)

• Estimated Complexity: Unknown
• Assignee: Unassigned
• Reporter: Josh Reagan
• Created: 10/Apr/24 18:54
• Updated: 15/Apr/24 17:06
• Resolved: 13/Apr/24 11:03

Description

The `DefaultMapStructFinder` is unable to locate the `Mapper` classes when running in Spring Boot. Seems to throw an exception calling `PluginHelper.getPackageScanClassResolver(ecc).findByFilter(f -> f.getName().endsWith("Mapper"), names);` inside the `doInit()` method.

You can work around this by creating your own `MapStructFinder`, extending `DefaultMapStructFinder`, overriding the `doInit()` function, and calling `discoverMappings(...)` with each of your `Mapper` classes. That way it doesn't try to scan the classpath to find the `Mapper` classes automatically. I've attached a working example to illustrate.

*Note: It has no issue locating them when running `mvn spring-boot:run`. Only when running from the packaged uber jar with `java -jar ...`.