[MRESOLVER-519] Drop almost equal/same method copies (#452)

And introduce one in parent class.
---

https://issues.apache.org/jira/browse/MRESOLVER-519

Author: cstamas

maven-resolver-impl/src/main/java/org/eclipse/aether/internal/impl/collect/DependencyCollectorDelegate.java

@@ -458,6 +458,30 @@ protected static List<? extends Version> filterVersions(
         return versions;
     }
 
+    protected ArtifactDescriptorResult resolveCachedArtifactDescriptor(
+            DataPool pool,
+            ArtifactDescriptorRequest descriptorRequest,
+            RepositorySystemSession session,
+            Dependency d,
+            Results results,
+            List<DependencyNode> nodes) {
+        Object key = pool.toKey(descriptorRequest);
+        ArtifactDescriptorResult descriptorResult = pool.getDescriptor(key, descriptorRequest);
+        if (descriptorResult == null) {
+            try {
+                descriptorResult = descriptorReader.readArtifactDescriptor(session, descriptorRequest);
+                pool.putDescriptor(key, descriptorResult);
+            } catch (ArtifactDescriptorException e) {
+                results.addException(d, e, nodes);
+                pool.putDescriptor(key, e);
+                return null;
+            }
+        } else if (descriptorResult == DataPool.NO_DESCRIPTOR) {
+            return null;
+        }
+        return descriptorResult;
+    }
+
     /**
      * Helper class used during collection.
      */

maven-resolver-impl/src/main/java/org/eclipse/aether/internal/impl/collect/bf/BfDependencyCollector.java

@@ -67,7 +67,6 @@
 import org.eclipse.aether.internal.impl.collect.DependencyCollectorDelegate;
 import org.eclipse.aether.internal.impl.collect.PremanagedDependency;
 import org.eclipse.aether.repository.RemoteRepository;
-import org.eclipse.aether.resolution.ArtifactDescriptorException;
 import org.eclipse.aether.resolution.ArtifactDescriptorRequest;
 import org.eclipse.aether.resolution.ArtifactDescriptorResult;
 import org.eclipse.aether.resolution.VersionRangeRequest;
@@ -467,32 +466,12 @@ private ArtifactDescriptorResult resolveDescriptorForVersion(
         return isLackingDescriptor(args.session, newArtifact)
                 ? new ArtifactDescriptorResult(descriptorRequest)
                 : resolveCachedArtifactDescriptor(
-                        args.pool, descriptorRequest, args.session, newContext.withDependency(newDependency), results);
-    }
-
-    private ArtifactDescriptorResult resolveCachedArtifactDescriptor(
-            DataPool pool,
-            ArtifactDescriptorRequest descriptorRequest,
-            RepositorySystemSession session,
-            DependencyProcessingContext context,
-            Results results) {
-        Object key = pool.toKey(descriptorRequest);
-        ArtifactDescriptorResult descriptorResult = pool.getDescriptor(key, descriptorRequest);
-        if (descriptorResult == null) {
-            try {
-                descriptorResult = descriptorReader.readArtifactDescriptor(session, descriptorRequest);
-                pool.putDescriptor(key, descriptorResult);
-            } catch (ArtifactDescriptorException e) {
-                results.addException(context.dependency, e, context.parents);
-                pool.putDescriptor(key, e);
-                return null;
-            }
-
-        } else if (descriptorResult == DataPool.NO_DESCRIPTOR) {
-            return null;
-        }
-
-        return descriptorResult;
+                        args.pool,
+                        descriptorRequest,
+                        args.session,
+                        newContext.withDependency(newDependency).dependency,
+                        results,
+                        context.parents);
     }
 
     static class ParallelDescriptorResolver implements Closeable {

maven-resolver-impl/src/main/java/org/eclipse/aether/internal/impl/collect/df/DfDependencyCollector.java

@@ -48,7 +48,6 @@
 import org.eclipse.aether.internal.impl.collect.DependencyCollectorDelegate;
 import org.eclipse.aether.internal.impl.collect.PremanagedDependency;
 import org.eclipse.aether.repository.RemoteRepository;
-import org.eclipse.aether.resolution.ArtifactDescriptorException;
 import org.eclipse.aether.resolution.ArtifactDescriptorRequest;
 import org.eclipse.aether.resolution.ArtifactDescriptorResult;
 import org.eclipse.aether.resolution.VersionRangeRequest;
@@ -368,33 +367,8 @@ private ArtifactDescriptorResult getArtifactDescriptorResult(
             ArtifactDescriptorRequest descriptorRequest) {
         return noDescriptor
                 ? new ArtifactDescriptorResult(descriptorRequest)
-                : resolveCachedArtifactDescriptor(args.pool, descriptorRequest, args.session, d, results, args);
-    }
-
-    private ArtifactDescriptorResult resolveCachedArtifactDescriptor(
-            DataPool pool,
-            ArtifactDescriptorRequest descriptorRequest,
-            RepositorySystemSession session,
-            Dependency d,
-            Results results,
-            Args args) {
-        Object key = pool.toKey(descriptorRequest);
-        ArtifactDescriptorResult descriptorResult = pool.getDescriptor(key, descriptorRequest);
-        if (descriptorResult == null) {
-            try {
-                descriptorResult = descriptorReader.readArtifactDescriptor(session, descriptorRequest);
-                pool.putDescriptor(key, descriptorResult);
-            } catch (ArtifactDescriptorException e) {
-                results.addException(d, e, args.nodes.nodes);
-                pool.putDescriptor(key, e);
-                return null;
-            }
-
-        } else if (descriptorResult == DataPool.NO_DESCRIPTOR) {
-            return null;
-        }
-
-        return descriptorResult;
+                : resolveCachedArtifactDescriptor(
+                        args.pool, descriptorRequest, args.session, d, results, args.nodes.nodes);
     }
 
     static class Args {