IPROTO-311 Simple enums

core/src/main/java/org/infinispan/protostream/annotations/Proto.java

@@ -7,10 +7,17 @@
 import java.lang.annotation.Target;
 
 /**
- * Defines a Protocol Buffers message without having to annotate all fields with {@link ProtoField}.
- * Use this annotation to quickly generate messages from records or classes with public fields.
- * Fields must be public and they will be assigned incremental numbers based on the declaration order.
- * It is possible to override the automated defaults for a field by using the {@link ProtoField} annotation.
+ * Defines a Protocol Buffers message or enum without having to annotate all fields with {@link ProtoField} or {@link ProtoEnumValue}.
+ * <p>
+ *   Use this annotation on records or classes with public fields to quickly generate protocol buffers messages.
+ *   Fields must be public and they will be assigned incremental numbers based on the declaration order.
+ *   It is possible to override the automated defaults for a field by using the {@link ProtoField} annotation.
+ * </p>
+ * <p>
+ *   Use this annotation on Java enums to quickly generate protocol buffer enums.
+ *   The enums will use the natural ordinal number of the values.
+ *   It is possible to override the automated defaults for an enum value by using the {@link ProtoEnumValue} annotation.
+ * </p>
  *
  * @since 5.0
  */

core/src/main/java/org/infinispan/protostream/annotations/impl/ProtoEnumTypeMetadata.java

@@ -5,6 +5,7 @@
 import java.util.SortedMap;
 import java.util.TreeMap;
 
+import org.infinispan.protostream.annotations.Proto;
 import org.infinispan.protostream.annotations.ProtoEnumValue;
 import org.infinispan.protostream.annotations.ProtoName;
 import org.infinispan.protostream.annotations.ProtoSchemaBuilderException;
@@ -73,20 +74,21 @@ public boolean isAdapter() {
 
    @Override
    public void scanMemberAnnotations() {
+      final boolean implicit = annotatedEnumClass.getAnnotation(Proto.class) != null;
       if (membersByNumber == null) {
          membersByNumber = new TreeMap<>();
          membersByName = new HashMap<>();
          for (XEnumConstant ec : annotatedEnumClass.getEnumConstants()) {
             ProtoEnumValue annotation = ec.getAnnotation(ProtoEnumValue.class);
-            if (annotation == null) {
-               throw new ProtoSchemaBuilderException("Enum constants must have the @ProtoEnumValue annotation: " + getAnnotatedClassName() + '.' + ec.getName());
+            if (annotation == null && !implicit) {
+               throw Log.LOG.explicitEnumValueAnnotations(ec.getName(), annotatedEnumClass.getName());
             }
-            int number = getNumber(annotation, ec);
+            int number = annotation == null ? ec.getOrdinal() : getNumber(annotation, ec);
             if (membersByNumber.containsKey(number)) {
                throw new ProtoSchemaBuilderException("Found duplicate definition of Protobuf enum tag " + number + " on enum constant: " + getAnnotatedClassName() + '.' + ec.getName()
                      + " clashes with " + membersByNumber.get(number).getJavaEnumName());
             }
-            String name = annotation.name();
+            String name = annotation == null ? ec.getName() : annotation.name();
             if (name.isEmpty()) {
                name = ec.getName();
             }

core/src/main/java/org/infinispan/protostream/impl/Log.java

@@ -114,6 +114,9 @@ default MalformedProtobufException messageTruncated() {
    @Message(value = "@ProtoFactory annotated method has wrong return type: %s", id = 28)
    ProtoSchemaBuilderException wrongFactoryReturnType(String s);
 
+   @Message(value = "Value `%s` on enum `%s` must be annotated with @ProtoEnumValue", id = 29)
+   ProtoSchemaBuilderException explicitEnumValueAnnotations(String value, String name);
+
    class LogFactory {
       public static Log getLog(Class<?> clazz) {
          return Logger.getMessageLogger(Log.class, clazz.getName());

processor/src/main/java/org/infinispan/protostream/annotations/impl/processor/AnnotatedClassScanner.java

@@ -155,7 +155,7 @@ void discoverClasses(RoundEnvironment roundEnv) throws AnnotationProcessingExcep
          }
 
          for (Element e : roundEnv.getElementsAnnotatedWith(Proto.class)) {
-            visitProtoMessage(e);
+            visitProto(e);
          }
 
          for (Element e : roundEnv.getElementsAnnotatedWith(ProtoAdapter.class)) {
@@ -187,7 +187,7 @@ private void visitTypeElement(TypeElement e) {
          visitProtoName(e);
       }
       if (e.getAnnotation(Proto.class) != null) {
-         visitProtoMessage(e);
+         visitProto(e);
       }
 
       for (Element member : e.getEnclosedElements()) {
@@ -238,29 +238,27 @@ private void visitProtoAdapter(Element e) {
    }
 
    private void visitProtoTypeId(Element e) {
-      if (e.getKind() != ElementKind.CLASS && e.getKind() != ElementKind.INTERFACE && e.getKind() != ElementKind.ENUM) {
-         throw new AnnotationProcessingException(e, "@ProtoTypeId can only be applied to classes, interfaces and enums.");
+      switch (e.getKind()) {
+         case CLASS, INTERFACE, RECORD, ENUM -> collectClasses((TypeElement) e);
+         default ->
+               throw new AnnotationProcessingException(e, "@ProtoTypeId can only be applied to classes, records, interfaces and enums.");
       }
-      collectClasses((TypeElement) e);
    }
 
    private void visitProtoName(Element e) {
-      if (e.getKind() != ElementKind.CLASS && e.getKind() != ElementKind.INTERFACE && e.getKind() != ElementKind.ENUM) {
-         throw new AnnotationProcessingException(e, "@ProtoName can only be applied to classes, interfaces and enums.");
-      }
-      collectClasses((TypeElement) e);
-   }
-
-   private void visitProtoMessage(Element e) {
-      if (e.getKind() != ElementKind.CLASS && e.getKind() != ElementKind.INTERFACE && e.getKind() != ElementKind.RECORD) {
-         throw new AnnotationProcessingException(e, "@ProtoMessage can only be applied to classes and interfaces.");
+      switch (e.getKind()) {
+         case CLASS, INTERFACE, RECORD, ENUM -> collectClasses((TypeElement) e);
+         default ->
+               throw new AnnotationProcessingException(e, "@ProtoName can only be applied to classes, interfaces, records and enums.");
       }
       collectClasses((TypeElement) e);
    }
 
-   private void visitProtoEnum(Element e) {
-      if (e.getKind() != ElementKind.CLASS && e.getKind() != ElementKind.INTERFACE) {
-         throw new AnnotationProcessingException(e, "@ProtoEnum can only be applied to enums.");
+   private void visitProto(Element e) {
+      switch (e.getKind()) {
+         case CLASS, INTERFACE, RECORD, ENUM -> collectClasses((TypeElement) e);
+         default ->
+               throw new AnnotationProcessingException(e, "@Proto can only be applied to classes, interfaces, records and enums.");
       }
       collectClasses((TypeElement) e);
    }

processor/src/main/java/org/infinispan/protostream/annotations/impl/processor/CompileTimeProtoSchemaGenerator.java

@@ -15,7 +15,6 @@
 import org.infinispan.protostream.annotations.impl.AbstractMarshallerCodeGenerator;
 import org.infinispan.protostream.annotations.impl.BaseProtoSchemaGenerator;
 import org.infinispan.protostream.annotations.impl.ImportedProtoTypeMetadata;
-import org.infinispan.protostream.annotations.impl.ProtoEnumTypeMetadata;
 import org.infinispan.protostream.annotations.impl.ProtoTypeMetadata;
 import org.infinispan.protostream.annotations.impl.processor.dependency.CompileTimeDependency;
 import org.infinispan.protostream.annotations.impl.processor.types.MirrorTypeFactory;
@@ -52,11 +51,6 @@ protected AbstractMarshallerCodeGenerator makeMarshallerCodeGenerator() {
       return marshallerSourceCodeGenerator;
    }
 
-   @Override
-   protected ProtoTypeMetadata makeEnumTypeMetadata(XClass javaType) {
-      return new ProtoEnumTypeMetadata(javaType, getTargetClass(javaType));
-   }
-
    @Override
    protected ProtoTypeMetadata makeMessageTypeMetadata(XClass javaType) {
       XClass targetClass = getTargetClass(javaType);

processor/src/test/java/org/infinispan/protostream/annotations/impl/processor/tests/ProtoSchemaTest.java

@@ -1384,16 +1384,25 @@ public void testGenericMessage() throws Exception {
       assertEquals("asdfg", ((GenericMessage.OtherMessage) genericMessage.field4.getValue()).field1);
    }
 
+   @Proto
+   enum BareEnum {
+      ZERO,
+      ONE,
+      TWO
+   }
+
    @Proto
    static final class BareMessage {
       public int anInt;
       public String aString;
       public List<String> things;
       public Map<String, String> moreThings;
+      public BareEnum anEnum;
    }
 
    @ProtoSchema(schemaFileName = "bare_message.proto",
          includeClasses = {
+               BareEnum.class,
                BareMessage.class,
          }, syntax = ProtoSyntax.PROTO3
    )
@@ -1430,6 +1439,10 @@ public void testBareMessage() {
       assertEquals(4, map.getNumber());
       assertEquals(Type.STRING, map.getKeyType());
       assertEquals(Type.STRING, map.getType());
+      field = message.getFields().get(4);
+      assertEquals("anEnum", field.getName());
+      assertEquals(5, field.getNumber());
+      assertEquals(Type.ENUM, field.getType());
    }
 
    //todo warnings logged to log4j during generation do not end up in compiler's message log