Review: We have to always ensure the whole component type chain is pr…

…esent. Background is, that if those component types are not referenced in another place (e.g. the two-dim component type is not also a field type somewhere, etc.), we will otherwise create a "simple" class stub here on the fly, and that simple stub will not get processed anymore and thus will not get any component type. In other words, the component type chain would then be broken.

Issue: #187
Signed-off-by: Peter Gafert <peter.gafert@tngtech.com>

archunit/src/main/java/com/tngtech/archunit/core/domain/ImportContext.java

@@ -57,5 +57,5 @@ public interface ImportContext {
 
     Set<ThrowsDeclaration<JavaConstructor>> getConstructorThrowsDeclarationsOfType(JavaClass javaClass);
 
-    Optional<JavaClass> resolveComponentType(JavaType type);
+    JavaClass resolveClass(String fullyQualifiedClassName);
 }

archunit/src/main/java/com/tngtech/archunit/core/domain/JavaClass.java

@@ -847,7 +847,7 @@ public Map<String, JavaAnnotation> get() {
     }
 
     CompletionProcess completeFrom(ImportContext context) {
-        componentType = context.resolveComponentType(javaType);
+        completeComponentType(context);
         enclosingClass = context.createEnclosingClass(this);
         memberDependenciesOnClass = new MemberDependenciesOnClass(
                 context.getFieldsOfType(this),
@@ -859,6 +859,15 @@ CompletionProcess completeFrom(ImportContext context) {
         return new CompletionProcess();
     }
 
+    private void completeComponentType(ImportContext context) {
+        JavaClass current = this;
+        while (current.isArray() && !current.componentType.isPresent()) {
+            JavaClass componentType = context.resolveClass(current.javaType.tryGetComponentType().get().getName());
+            current.componentType = Optional.of(componentType);
+            current = componentType;
+        }
+    }
+
     @Override
     public String toString() {
         return "JavaClass{name='" + javaType.getName() + "\'}";

archunit/src/main/java/com/tngtech/archunit/core/importer/ClassGraphCreator.java

@@ -40,7 +40,6 @@
 import com.tngtech.archunit.core.domain.JavaMethod;
 import com.tngtech.archunit.core.domain.JavaMethodCall;
 import com.tngtech.archunit.core.domain.JavaStaticInitializer;
-import com.tngtech.archunit.core.domain.JavaType;
 import com.tngtech.archunit.core.domain.ThrowsDeclaration;
 import com.tngtech.archunit.core.importer.AccessRecord.FieldAccessRecord;
 import com.tngtech.archunit.core.importer.DomainBuilders.JavaConstructorCallBuilder;
@@ -277,13 +276,8 @@ public Optional<JavaClass> createEnclosingClass(JavaClass owner) {
     }
 
     @Override
-    public Optional<JavaClass> resolveComponentType(JavaType array) {
-        return array.tryGetComponentType().transform(new Function<JavaType, JavaClass>() {
-            @Override
-            public JavaClass apply(JavaType input) {
-                return classes.getOrResolve(input.getName());
-            }
-        });
+    public JavaClass resolveClass(String fullyQualifiedClassName) {
+        return classes.getOrResolve(fullyQualifiedClassName);
     }
 
     private static class MemberDependenciesByTarget {
@@ -347,4 +341,4 @@ Set<ThrowsDeclaration<JavaConstructor>> getConstructorThrowsDeclarationsOfType(J
             return constructorThrowsDeclarationDependencies.get(javaClass);
         }
     }
-}
+}

archunit/src/test/java/com/tngtech/archunit/core/domain/JavaClassTest.java

@@ -105,6 +105,27 @@ public void finds_multidimensional_array_type() {
         assertThat(oneDimArray.tryGetComponentType().get()).isEqualTo(type);
         assertThat(twoDimArray.isArray()).isTrue();
         assertThat(twoDimArray.tryGetComponentType().get()).isEqualTo(oneDimArray);
+        assertThat(twoDimArray.tryGetComponentType().get().tryGetComponentType().get()).isEqualTo(type);
+    }
+
+    @Test
+    public void finds_component_type_chain_of_otherwise_unreferenced_component_type() {
+        class OnlyReferencingMultiDimArray {
+            OnlyReferencingMultiDimArray[][][] field;
+        }
+
+        JavaClass javaClass = importClassesWithContext(OnlyReferencingMultiDimArray.class)
+                .get(OnlyReferencingMultiDimArray.class);
+
+        JavaClass arrayType = javaClass.getField("field").getRawType();
+        JavaClass twoDim = arrayType.tryGetComponentType().get();
+        assertThat(twoDim.getName()).isEqualTo(OnlyReferencingMultiDimArray[][].class.getName());
+
+        JavaClass oneDim = twoDim.tryGetComponentType().get();
+        assertThat(oneDim.getName()).isEqualTo(OnlyReferencingMultiDimArray[].class.getName());
+
+        JavaClass original = oneDim.tryGetComponentType().get();
+        assertThat(original).isEqualTo(javaClass);
     }
 
     @Test

archunit/src/test/java/com/tngtech/archunit/core/importer/ImportTestUtils.java

@@ -430,8 +430,8 @@ public Set<ThrowsDeclaration<JavaConstructor>> getConstructorThrowsDeclarationsO
         }
 
         @Override
-        public Optional<JavaClass> resolveComponentType(JavaType type) {
-            return Optional.absent();
+        public JavaClass resolveClass(String fullyQualifiedClassName) {
+            throw new UnsupportedOperationException("Override me where necessary");
         }
     }
-}
+}