Change PlatformArtifactFactory to only emit classifier strings

src/main/java/io/github/ascopes/protobufmavenplugin/dependency/BinaryPluginResolver.java

@@ -38,19 +38,19 @@
 public final class BinaryPluginResolver {
 
   private final MavenDependencyPathResolver dependencyResolver;
-  private final PlatformArtifactFactory platformDependencyFactory;
+  private final PlatformClassifierFactory platformClassifierFactory;
   private final SystemPathBinaryResolver systemPathResolver;
   private final UrlResourceFetcher urlResourceFetcher;
 
   @Inject
   public BinaryPluginResolver(
       MavenDependencyPathResolver dependencyResolver,
-      PlatformArtifactFactory platformDependencyFactory,
+      PlatformClassifierFactory platformClassifierFactory,
       SystemPathBinaryResolver systemPathResolver,
       UrlResourceFetcher urlResourceFetcher
   ) {
     this.dependencyResolver = dependencyResolver;
-    this.platformDependencyFactory = platformDependencyFactory;
+    this.platformClassifierFactory = platformClassifierFactory;
     this.systemPathResolver = systemPathResolver;
     this.urlResourceFetcher = urlResourceFetcher;
   }
@@ -78,13 +78,10 @@ private ResolvedPlugin resolveMavenPlugin(
       MavenSession session,
       MavenArtifact plugin
   ) throws ResolutionException {
-    plugin = platformDependencyFactory.createArtifact(
-        plugin.getGroupId().orElse(null),
-        plugin.getArtifactId().orElse(null),
-        plugin.getVersion().orElse(null),
-        plugin.getType().orElse("exe"),
-        plugin.getClassifier().orElse(null)
-    );
+    var artifactId = plugin.getArtifactId().orElse(null);
+    var classifier = plugin.getClassifier()
+            .orElseGet(() -> platformClassifierFactory.getClassifier(artifactId));
+    plugin.setClassifier(classifier);
 
     // Only one dependency should ever be returned here.
     var path = dependencyResolver.resolveOne(session, plugin, DependencyResolutionDepth.DIRECT)

src/main/java/io/github/ascopes/protobufmavenplugin/dependency/PlatformArtifactFactory.java → src/main/java/io/github/ascopes/protobufmavenplugin/dependency/PlatformClassifierFactory.java

@@ -16,49 +16,26 @@
 
 package io.github.ascopes.protobufmavenplugin.dependency;
 
-import static java.util.Objects.requireNonNullElse;
-import static java.util.Objects.requireNonNullElseGet;
-
-import io.github.ascopes.protobufmavenplugin.MavenArtifact;
 import io.github.ascopes.protobufmavenplugin.platform.HostSystem;
 import javax.inject.Inject;
 import javax.inject.Named;
-import org.jspecify.annotations.Nullable;
 
 /**
- * Factory that can produce dependencies marked with platform-specific classifiers.
+ * Factory that can produce classifiers for dependencies based on the current platform.
  *
  * @author Ashley Scopes
  */
 @Named
-public final class PlatformArtifactFactory {
+public final class PlatformClassifierFactory {
+
   private final HostSystem hostSystem;
 
   @Inject
-  public PlatformArtifactFactory(HostSystem hostSystem) {
+  public PlatformClassifierFactory(HostSystem hostSystem) {
     this.hostSystem = hostSystem;
   }
 
-  public MavenArtifact createArtifact(
-      String groupId,
-      String artifactId,
-      String version,
-      @Nullable String extension,
-      @Nullable String classifier
-  ) {
-    var artifact = new MavenArtifact();
-    artifact.setGroupId(groupId);
-    artifact.setArtifactId(artifactId);
-    artifact.setVersion(version);
-    artifact.setType(requireNonNullElse(extension, "exe"));
-    artifact.setClassifier(requireNonNullElseGet(
-        classifier,
-        () -> getPlatformExecutableClassifier(artifactId)
-    ));
-    return artifact;
-  }
-
-  private String getPlatformExecutableClassifier(String artifactId) {
+  public String getClassifier(String artifactId) {
     var rawOs = hostSystem.getOperatingSystem();
     var rawArch = hostSystem.getCpuArchitecture();
 

src/main/java/io/github/ascopes/protobufmavenplugin/dependency/ProtocResolver.java

@@ -17,6 +17,7 @@
 package io.github.ascopes.protobufmavenplugin.dependency;
 
 import io.github.ascopes.protobufmavenplugin.DependencyResolutionDepth;
+import io.github.ascopes.protobufmavenplugin.MavenArtifact;
 import io.github.ascopes.protobufmavenplugin.platform.FileUtils;
 import io.github.ascopes.protobufmavenplugin.platform.HostSystem;
 import java.io.IOException;
@@ -44,21 +45,21 @@ public final class ProtocResolver {
 
   private final HostSystem hostSystem;
   private final MavenDependencyPathResolver dependencyResolver;
-  private final PlatformArtifactFactory platformArtifactFactory;
+  private final PlatformClassifierFactory platformClassifierFactory;
   private final SystemPathBinaryResolver systemPathResolver;
   private final UrlResourceFetcher urlResourceFetcher;
 
   @Inject
   public ProtocResolver(
       HostSystem hostSystem,
       MavenDependencyPathResolver dependencyResolver,
-      PlatformArtifactFactory platformArtifactFactory,
+      PlatformClassifierFactory platformClassifierFactory,
       SystemPathBinaryResolver systemPathResolver,
       UrlResourceFetcher urlResourceFetcher
   ) {
     this.hostSystem = hostSystem;
     this.dependencyResolver = dependencyResolver;
-    this.platformArtifactFactory = platformArtifactFactory;
+    this.platformClassifierFactory = platformClassifierFactory;
     this.systemPathResolver = systemPathResolver;
     this.urlResourceFetcher = urlResourceFetcher;
   }
@@ -107,13 +108,12 @@ private Path resolveFromMavenRepositories(
       );
     }
 
-    var artifact = platformArtifactFactory.createArtifact(
-        GROUP_ID,
-        ARTIFACT_ID,
-        version,
-        null,
-        null
-    );
+    var artifact = new MavenArtifact();
+    artifact.setGroupId(GROUP_ID);
+    artifact.setArtifactId(ARTIFACT_ID);
+    artifact.setVersion(version);
+    artifact.setType("exe");
+    artifact.setClassifier(platformClassifierFactory.getClassifier(ARTIFACT_ID));
 
     return dependencyResolver.resolveOne(session, artifact, DependencyResolutionDepth.DIRECT)
         .iterator()