[MDEP-594] Dependency reported as "unused declared" when runtime-retention type annotation is used

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Resolved
• Affects Version/s: 3.0.0
• Fix Version/s: 3.1.0
• Component/s: analyze
• Environment: Apache Maven 3.5.0, ; Oracle Java version: 1.8.0_144
• Assignee: Unassigned
• Reporter: Andreas Hubold
• Created: 21/Dec/17 13:34
• Updated: 06/Jan/19 21:32
• Resolved: 06/Jan/19 21:32

Description

In the attached example project, module "usage" uses annotation @Example:

public interface Usage {
  @Example String getEmail(); 
}

which is defined in module "annotation" as:

@Target({ElementType.TYPE_USE, ElementType.TYPE_PARAMETER})
@Retention(RetentionPolicy.RUNTIME)
public @interface Example {
}

Consequently, the pom.xml of module "usage" defines a compile-dependency to module "annotation" but the dependency:analyze-only goal incorrectly reports this as unused dependency:

[main] [INFO] --- maven-dependency-plugin:3.0.0:analyze-only (analyze-dependencies) @ usage ---
[main] [WARNING] Unused declared dependencies found:
[main] [WARNING]    com.example:annotation:jar:1.0-SNAPSHOT:compile

This false positive is only reported if

• the annotation is meta-annotated with target TYPE_USE + TYPE_PARAMETER
• and the source.version/target.version of the compiler plugin for module "usage" is 1.8

There's no false positive if the @Target meta-annotation is removed or if compiler's source/target version is set to 1.7.

Issue Links

• is blocked by: MSHARED-674 Maven Dependency Analyzer ignores Java 8 type annotations
• is related to: MSHARED-792 Maven Dependency Analyzer ignores Java 8 type annotations on local variables