Value.Default annotation is redundant for Java 8 default interface

method #125
immutables · Jun 30, 2015 · ad64b08 · ad64b08
1 parent 89aea68
commit ad64b08
Show file tree

Hide file tree

Showing 9 changed files with 81 additions and 13 deletions.
diff --git a/value-annotations/src/org/immutables/value/Value.java b/value-annotations/src/org/immutables/value/Value.java
@@ -531,6 +531,15 @@
      */
     boolean allParameters() default false;
 
+    /**
+     * This funny-named named attribute, when enabled makes default accessor methods defined in
+     * interfaces/traits to behave as if they annotated as {@literal @}{@link Value.Default}.
+     * This is not a default behaviour to preserve compatibility and also to have an choice to not
+     * opt-in for this new functionality when not needed.
+     * @return if consider default method accessors as {@literal @}{@code Value.Default}
+     */
+    boolean defaultAsDefault() default false;
+
     /**
      * List type of annotations to copy over from abstract value type to immutable implementation
      * class. Very often this functionality is not needed when annoatations are declared as

diff --git a/value-fixture/src/org/immutables/fixture/DefaultAsDefault.java b/value-fixture/src/org/immutables/fixture/DefaultAsDefault.java
@@ -0,0 +1,15 @@
+package org.immutables.fixture;
+
+import org.immutables.value.Value;
+
+@Value.Immutable
+@Value.Style(defaultAsDefault = true)
+public interface DefaultAsDefault {
+  default int a() {
+    return 1;
+  }
+
+  default int b() {
+    return 2;
+  }
+}
diff --git a/value-fixture/test/org/immutables/fixture/ValuesTest.java b/value-fixture/test/org/immutables/fixture/ValuesTest.java
@@ -102,6 +102,16 @@ public void resetCollectionTest() {
     check(a).is(b);
   }
 
+  @Test
+  public void defaultAsDefault() {
+    DefaultAsDefault d = ImmutableDefaultAsDefault.builder()
+        .b(1)
+        .build();
+
+    check(d.a()).is(1);
+    check(d.b()).is(1);
+  }
+
   @Test
   public void extendsBuilderIfaceValue() {
     ExtendedBuilderInterface ifc = ExtendedBuilderInterface.builder()

diff --git a/value-processor/src/org/immutables/value/processor/meta/AccessorAttributesCollector.java b/value-processor/src/org/immutables/value/processor/meta/AccessorAttributesCollector.java
@@ -188,10 +188,17 @@ private void processGenerationCandidateMethod(ExecutableElement attributeMethodC
       }
     }
 
-    if (isDiscoveredAttribute(attributeMethodCandidate)) {
+    boolean useDefaultAsDefault = type.constitution.style().defaultAsDefault();
+
+    if (isDiscoveredAttribute(attributeMethodCandidate, useDefaultAsDefault)) {
       TypeMirror returnType = resolveReturnType(attributeMethodCandidate);
 
       ValueAttribute attribute = new ValueAttribute();
+      attribute.reporter = reporter;
+      attribute.returnType = returnType;
+      attribute.names = deriveNames(name.toString());
+      attribute.element = attributeMethodCandidate;
+      attribute.containingType = type;
 
       boolean isFinal = isFinal(attributeMethodCandidate);
       boolean isAbstract = isAbstract(attributeMethodCandidate);
@@ -239,8 +246,17 @@ private void processGenerationCandidateMethod(ExecutableElement attributeMethodC
             .error("Annotated attribute '%s' will be overriden and cannot be final", name);
       } else if (defaultAnnotationPresent) {
         attribute.isGenerateDefault = true;
+
+        if (useDefaultAsDefault && attribute.isInterfaceDefaultMethod()) {
+          report(attributeMethodCandidate)
+              .annotationNamed(DefaultMirror.simpleName())
+              .warning("@Value.Default annotation is superflous for default annotation attribute"
+                  + " when 'defaultAsDefault' style is enabled");
+        }
       } else if (derivedAnnotationPresent) {
         attribute.isGenerateDerived = true;
+      } else if (useDefaultAsDefault) {
+        attribute.isGenerateDefault = attribute.isInterfaceDefaultMethod();
       }
 
       if (LazyMirror.isPresent(attributeMethodCandidate)) {
@@ -252,14 +268,10 @@ private void processGenerationCandidateMethod(ExecutableElement attributeMethodC
               .error("@Value.Lazy attribute '%s' cannot be @Value.Derived or @Value.Default", name);
         } else {
           attribute.isGenerateLazy = true;
+          attribute.isGenerateDefault = false;
         }
       }
 
-      attribute.reporter = reporter;
-      attribute.returnType = returnType;
-      attribute.names = deriveNames(name.toString());
-      attribute.element = attributeMethodCandidate;
-      attribute.containingType = type;
       attributes.add(attribute);
 
       // Compute this eagerly here, for no strong reason
@@ -333,10 +345,12 @@ private static boolean isFinal(Element element) {
     return element.getModifiers().contains(Modifier.FINAL);
   }
 
-  private static boolean isDiscoveredAttribute(ExecutableElement attributeMethodCandidate) {
+  private static boolean isDiscoveredAttribute(ExecutableElement attributeMethodCandidate, boolean isDefaultAsDefault) {
     return attributeMethodCandidate.getParameters().isEmpty()
         && attributeMethodCandidate.getReturnType().getKind() != TypeKind.VOID
-        && (isAbstract(attributeMethodCandidate) || hasGenerateAnnotation(attributeMethodCandidate));
+        && (isAbstract(attributeMethodCandidate)
+            || hasGenerateAnnotation(attributeMethodCandidate)
+            || isDefaultAsDefault);
   }
 
   private static boolean hasGenerateAnnotation(ExecutableElement attributeMethodCandidate) {

diff --git a/value-processor/src/org/immutables/value/processor/meta/Proto.java b/value-processor/src/org/immutables/value/processor/meta/Proto.java
@@ -983,6 +983,7 @@ public StyleInfo apply(StyleMirror input) {
           ToImmutableInfo.FUNCTION.apply(input.defaults()),
           input.strictBuilder(),
           input.allParameters(),
+          input.defaultAsDefault(),
           input.jdkOnly(),
           ImmutableSet.copyOf(input.passAnnotationsName()),
           input.visibility());

diff --git a/value-processor/src/org/immutables/value/processor/meta/StyleInfo.java b/value-processor/src/org/immutables/value/processor/meta/StyleInfo.java
@@ -118,6 +118,10 @@ public Class<? extends Annotation> annotationType() {
   @Override
   public abstract boolean allParameters();
 
+  @Value.Parameter
+  @Override
+  public abstract boolean defaultAsDefault();
+
   @Value.Parameter
   @Override
   public abstract boolean jdkOnly();

diff --git a/value-processor/src/org/immutables/value/processor/meta/ValueAttribute.java b/value-processor/src/org/immutables/value/processor/meta/ValueAttribute.java
@@ -324,25 +324,29 @@ public boolean isGuavaImmutableDeclared() {
   }
 
   @Nullable
-  private CharSequence defaultInterface;
+  private String defaultInterface;
 
-  public CharSequence defaultInterface() {
+  public String defaultInterface() {
     if (defaultInterface == null) {
       defaultInterface = inferDefaultInterface();
     }
     return defaultInterface;
   }
 
-  private CharSequence inferDefaultInterface() {
+  private String inferDefaultInterface() {
-    if (element.getEnclosingElement().getKind() == ElementKind.INTERFACE
+    if (isInterfaceDefaultMethod()) {
-        && !element.getModifiers().contains(Modifier.ABSTRACT)) {
       if (containingType.element.getKind() == ElementKind.INTERFACE) {
         return containingType.typeAbstract().relative();
       }
     }
     return "";
   }
 
+  public boolean isInterfaceDefaultMethod() {
+    return element.getEnclosingElement().getKind() == ElementKind.INTERFACE
+        && !element.getModifiers().contains(Modifier.ABSTRACT);
+  }
+
   public boolean isGenerateEnumMap() {
     return typeKind.isEnumMap();
   }

diff --git a/value-processor/src/org/immutables/value/processor/meta/ValueMirrors.java b/value-processor/src/org/immutables/value/processor/meta/ValueMirrors.java
@@ -121,6 +121,8 @@ private ValueMirrors() {}
 
     boolean allParameters() default false;
 
+    boolean defaultAsDefault() default false;
+
     boolean jdkOnly() default false;
 
     Class<? extends Annotation>[] passAnnotations() default {};

diff --git a/value/src/org/immutables/value/Value.java b/value/src/org/immutables/value/Value.java
@@ -531,6 +531,15 @@
      */
     boolean allParameters() default false;
 
+    /**
+     * This funny-named named attribute, when enabled makes default accessor methods defined in
+     * interfaces/traits to behave as if they annotated as {@literal @}{@link Value.Default}.
+     * This is not a default behaviour to preserve compatibility and also to have an choice to not
+     * opt-in for this new functionality when not needed.
+     * @return if consider default method accessors as {@literal @}{@code Value.Default}
+     */
+    boolean defaultAsDefault() default false;
+
     /**
      * List type of annotations to copy over from abstract value type to immutable implementation
      * class. Very often this functionality is not needed when annoatations are declared as