ENH: meta-annotation support similar to spring.

See http://docs.spring.io/spring/docs/current/spring-framework-reference/html/beans.html#beans-meta-annotations for detailed explanation

src/main/java/com/avaje/ebeaninternal/server/changelog/DefaultChangeLogRegister.java

@@ -5,6 +5,7 @@ import com.avaje.ebean.annotation.ChangeLogInsertMode;
 import com.avaje.ebean.event.BeanPersistRequest;
 import com.avaje.ebean.event.changelog.ChangeLogFilter;
 import com.avaje.ebean.event.changelog.ChangeLogRegister;
+import com.avaje.ebeaninternal.server.deploy.parse.AnnotationBase;
 
 import java.util.HashSet;
 import java.util.Set;
@@ -52,14 +53,7 @@ public class DefaultChangeLogRegister implements ChangeLogRegister {
    * Find and return the ChangeLog annotation in the inheritance hierarchy.
    */
   private ChangeLog getChangeLog(Class<?> beanType) {
-    ChangeLog changeLog = beanType.getAnnotation(ChangeLog.class);
-    if (changeLog != null) {
-      return changeLog;
-    }
-    if (Object.class.equals(beanType.getSuperclass())) {
-      return null;
-    }
-    return getChangeLog(beanType.getSuperclass());
+    return AnnotationBase.findAnnotation(beanType, ChangeLog.class);
   }
 
   /**

src/main/java/com/avaje/ebeaninternal/server/deploy/BeanDescriptorManager.java

@@ -38,6 +38,7 @@ import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssocMany;
 import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssocOne;
 import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanTable;
 import com.avaje.ebeaninternal.server.deploy.meta.DeployTableJoin;
+import com.avaje.ebeaninternal.server.deploy.parse.AnnotationBase;
 import com.avaje.ebeaninternal.server.deploy.parse.DeployBeanInfo;
 import com.avaje.ebeaninternal.server.deploy.parse.DeployCreateProperties;
 import com.avaje.ebeaninternal.server.deploy.parse.DeployInherit;
@@ -1457,7 +1458,7 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
    * If so it is ok for it not to be enhanced.
    */
   private boolean isMappedSuperWithNoProperties(Class<?> beanClass) {
-
+    // Attention: do not use AnnotationBase.findAnnotation(cls,...) here.
     MappedSuperclass annotation = beanClass.getAnnotation(MappedSuperclass.class);
     if (annotation == null) {
       return false;

src/main/java/com/avaje/ebeaninternal/server/deploy/meta/DeployBeanProperty.java

@@ -18,6 +18,7 @@ import com.avaje.ebeaninternal.server.core.InternString;
 import com.avaje.ebeaninternal.server.deploy.BeanProperty;
 import com.avaje.ebeaninternal.server.deploy.DeployDocPropertyOptions;
 import com.avaje.ebeaninternal.server.deploy.generatedproperty.GeneratedProperty;
+import com.avaje.ebeaninternal.server.deploy.parse.AnnotationBase;
 import com.avaje.ebeaninternal.server.el.ElPropertyValue;
 import com.avaje.ebeaninternal.server.properties.BeanPropertyGetter;
 import com.avaje.ebeaninternal.server.properties.BeanPropertySetter;
@@ -233,29 +234,29 @@ public class DeployBeanProperty {
     if (field == null) {
       return 0;
     }
-    if (field.getAnnotation(Id.class) != null) {
+    if (AnnotationBase.findAnnotation(field, Id.class) != null) {
       return ID_ORDER;
-    } else if (field.getAnnotation(EmbeddedId.class) != null) {
+    } else if (AnnotationBase.findAnnotation(field, EmbeddedId.class) != null) {
       return ID_ORDER;
     } else if (undirectionalShadow) {
       return UNIDIRECTIONAL_ORDER;
     } else if (isAuditProperty()) {
       return AUDITCOLUMN_ORDER;
-    } else if (field.getAnnotation(Version.class) != null) {
+    } else if (AnnotationBase.findAnnotation(field, Version.class) != null) {
       return VERSIONCOLUMN_ORDER;
-    } else if (field.getAnnotation(SoftDelete.class) != null) {
+    } else if (AnnotationBase.findAnnotation(field, SoftDelete.class) != null) {
       return VERSIONCOLUMN_ORDER;
     }
     return 0;
   }
 
   private boolean isAuditProperty() {
-    return (field.getAnnotation(WhenCreated.class) != null
-        || field.getAnnotation(WhenModified.class) != null
-        || field.getAnnotation(WhoModified.class) != null
-        || field.getAnnotation(WhoCreated.class) != null
-        || field.getAnnotation(UpdatedTimestamp.class) != null
-        || field.getAnnotation(CreatedTimestamp.class) != null);
+    return (AnnotationBase.findAnnotation(field, WhenCreated.class) != null
+        || AnnotationBase.findAnnotation(field, WhenModified.class) != null
+        || AnnotationBase.findAnnotation(field, WhoModified.class) != null
+        || AnnotationBase.findAnnotation(field, WhoCreated.class) != null
+        || AnnotationBase.findAnnotation(field, UpdatedTimestamp.class) != null
+        || AnnotationBase.findAnnotation(field, CreatedTimestamp.class) != null);
   }
 
   public String getFullBeanName() {

src/main/java/com/avaje/ebeaninternal/server/deploy/parse/AnnotationBase.java

@@ -1,8 +1,11 @@
 package com.avaje.ebeaninternal.server.deploy.parse;
 
 import java.lang.annotation.Annotation;
+import java.lang.reflect.AnnotatedElement;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
+import java.util.HashSet;
+import java.util.Set;
 
 import com.avaje.ebean.config.NamingConvention;
 import com.avaje.ebean.config.dbplatform.DatabasePlatform;
@@ -46,12 +49,12 @@ public abstract class AnnotationBase {
     T a = null;
     Field field = prop.getField();
     if (field != null) {
-      a = field.getAnnotation(annClass);
+      a = findAnnotation(field, annClass);
     }
     if (a == null) {
       Method m = prop.getReadMethod();
       if (m != null) {
-        a = m.getAnnotation(annClass);
+        a = findAnnotation(m, annClass);
       }
     }
     return a;
@@ -66,10 +69,95 @@ public abstract class AnnotationBase {
   protected <T extends Annotation> T find(DeployBeanProperty prop, Class<T> annClass) {
     T a = get(prop, annClass);
     if (a == null) {
-      a = prop.getOwningType().getAnnotation(annClass);
+      a = findAnnotation(prop.getOwningType(),annClass);
     }
     return a;
   }
 
+  
+  // this code is taken from the spring framework to find annotations recursively
+  
+  /**
+   * Determine if the supplied {@link Annotation} is defined in the core JDK
+   * {@code java.lang.annotation} package.
+   */
+  public static boolean isInJavaLangAnnotationPackage(Annotation annotation) {
+    return annotation.annotationType().getName().startsWith("java.lang.annotation");
+  }
+  
+  /**
+   * Find a single {@link Annotation} of {@code annotationType} on the
+   * supplied {@link AnnotatedElement}.
+   * <p>Meta-annotations will be searched if the annotation is not
+   * <em>directly present</em> on the supplied element.
+   * <p><strong>Warning</strong>: this method operates generically on
+   * annotated elements. In other words, this method does not execute
+   * specialized search algorithms for classes or methods. It only
+   * traverses through Annotations!</p>
+   */
+  public static <A extends Annotation> A findAnnotation(AnnotatedElement annotatedElement, Class<A> annotationType) {
+    if (annotationType == null) {
+      return null;
+    }
+    // check if directly present, if not, start recursive traversal
+    A ann = annotatedElement.getAnnotation(annotationType);
+    if (ann != null) {
+      return ann;
+    } else {
+      return findAnnotation(annotatedElement, annotationType, new HashSet<Annotation>());
+    }
+  }
 
+  /**
+   * Find a single {@link Annotation} of {@code annotationType} on the
+   * supplied {@link clazz}.
+   * <p>Meta-annotations will be searched if the annotation is not
+   * <em>directly present</em> on the supplied element.
+   * <p><strong>Note</strong>: this method searches for annotations at 
+   * class & superClass(es)!</p>
+   */
+  public static <A extends Annotation> A findAnnotation(Class<?> clazz, Class<A> annotationType) {
+    if (annotationType == null) {
+      return null;
+    }
+    // check if directly present, if not, start recursive traversal
+    A ann = clazz.getAnnotation(annotationType);
+    if (ann != null) {
+      return ann;
+    } else {
+      while (clazz != null && clazz != Object.class) {
+        ann = findAnnotation(clazz, annotationType, new HashSet<Annotation>());
+        if (ann != null) {
+          return ann;
+        }
+        // not present at this class - traverse to superclass
+        clazz = clazz.getSuperclass();
+      }
+      return null;
+    }
+  }
+  /**
+   * Perform the search algorithm for {@link #findAnnotation(AnnotatedElement, Class)}
+   * avoiding endless recursion by tracking which annotations have already
+   * been <em>visited</em>.
+   */
+  @SuppressWarnings("unchecked")
+  private static <A extends Annotation> A findAnnotation(AnnotatedElement annotatedElement, Class<A> annotationType, Set<Annotation> visited) {
+  
+      Annotation[] anns = annotatedElement.getDeclaredAnnotations();
+      for (Annotation ann : anns) {
+        if (ann.annotationType() == annotationType) {
+          return (A) ann;
+        }
+      }
+      for (Annotation ann : anns) {
+        if (!isInJavaLangAnnotationPackage(ann) && visited.add(ann)) {
+          A annotation = findAnnotation((AnnotatedElement) ann.annotationType(), annotationType, visited);
+          if (annotation != null) {
+            return annotation;
+          }
+        }
+      }
+    return null;
+  }
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/parse/AnnotationClass.java

@@ -66,7 +66,7 @@ public class AnnotationClass extends AnnotationParser {
   public void parseAttributeOverride() {
 
     Class<?> cls = descriptor.getBeanType();
-    AttributeOverride override = cls.getAnnotation(AttributeOverride.class);
+    AttributeOverride override = AnnotationBase.findAnnotation(cls,AttributeOverride.class);
     if (override != null) {
       String propertyName = override.name();
       Column column = override.column();
@@ -103,7 +103,7 @@ public class AnnotationClass extends AnnotationParser {
 
   private void read(Class<?> cls) {
 
-    Entity entity = cls.getAnnotation(Entity.class);
+    Entity entity = AnnotationBase.findAnnotation(cls,Entity.class);
     if (entity != null) {
       if (entity.name().equals("")) {
         descriptor.setName(cls.getSimpleName());
@@ -112,27 +112,27 @@ public class AnnotationClass extends AnnotationParser {
       }
     }
 
-    Embeddable embeddable = cls.getAnnotation(Embeddable.class);
+    Embeddable embeddable = AnnotationBase.findAnnotation(cls,Embeddable.class);
     if (embeddable != null) {
       descriptor.setEntityType(EntityType.EMBEDDED);
       descriptor.setName("Embeddable:" + cls.getSimpleName());
     }
 
-    Index index = cls.getAnnotation(Index.class);
+    Index index = AnnotationBase.findAnnotation(cls,Index.class);
     if (index != null) {
       descriptor.addIndex(new IndexDefinition(index.columnNames(), index.name(), index.unique()));
     }
 
-    UniqueConstraint uc = cls.getAnnotation(UniqueConstraint.class);
+    UniqueConstraint uc = AnnotationBase.findAnnotation(cls,UniqueConstraint.class);
     if (uc != null) {
       descriptor.addIndex(new IndexDefinition(uc.columnNames()));
     }
 
-    View view = cls.getAnnotation(View.class);
+    View view = AnnotationBase.findAnnotation(cls,View.class);
     if (view != null) {
       descriptor.setView(view.name(), view.dependentTables());
     }
-    Table table = cls.getAnnotation(Table.class);
+    Table table = AnnotationBase.findAnnotation(cls,Table.class);
     if (table != null) {
       UniqueConstraint[] uniqueConstraints = table.uniqueConstraints();
       for (UniqueConstraint c : uniqueConstraints) {
@@ -140,54 +140,54 @@ public class AnnotationClass extends AnnotationParser {
       }
     }
 
-    Draftable draftable = cls.getAnnotation(Draftable.class);
+    Draftable draftable = AnnotationBase.findAnnotation(cls,Draftable.class);
     if (draftable != null) {
       descriptor.setDraftable();
     }
 
-    DraftableElement draftableElement = cls.getAnnotation(DraftableElement.class);
+    DraftableElement draftableElement = AnnotationBase.findAnnotation(cls,DraftableElement.class);
     if (draftableElement != null) {
       descriptor.setDraftableElement();
     }
 
-    ReadAudit readAudit = cls.getAnnotation(ReadAudit.class);
+    ReadAudit readAudit = AnnotationBase.findAnnotation(cls,ReadAudit.class);
     if (readAudit != null) {
       descriptor.setReadAuditing();
     }
 
-    History history = cls.getAnnotation(History.class);
+    History history = AnnotationBase.findAnnotation(cls,History.class);
     if (history != null) {
       descriptor.setHistorySupport();
     }
 
-    DbComment comment = cls.getAnnotation(DbComment.class);
+    DbComment comment = AnnotationBase.findAnnotation(cls,DbComment.class);
     if (comment != null) {
       descriptor.setDbComment(comment.value());
     }
 
-    DocStore docStore = cls.getAnnotation(DocStore.class);
+    DocStore docStore = AnnotationBase.findAnnotation(cls,DocStore.class);
     if (docStore != null) {
       descriptor.readDocStore(docStore);
     }
 
-    UpdateMode updateMode = cls.getAnnotation(UpdateMode.class);
+    UpdateMode updateMode = AnnotationBase.findAnnotation(cls,UpdateMode.class);
     if (updateMode != null) {
       descriptor.setUpdateChangesOnly(updateMode.updateChangesOnly());
     }
 
-    Cache cache = cls.getAnnotation(Cache.class);
+    Cache cache = AnnotationBase.findAnnotation(cls,Cache.class);
     if (cache != null && !disableL2Cache) {
       descriptor.setCache(cache);
     }
 
-    NamedQueries namedQueries = cls.getAnnotation(NamedQueries.class);
+    NamedQueries namedQueries = AnnotationBase.findAnnotation(cls,NamedQueries.class);
     if (namedQueries != null) {
       for (NamedQuery namedQuery : namedQueries.value()) {
         descriptor.addNamedQuery(namedQuery.name(), namedQuery.query());
       }
     }
 
-    NamedQuery namedQuery = cls.getAnnotation(NamedQuery.class);
+    NamedQuery namedQuery = AnnotationBase.findAnnotation(cls,NamedQuery.class);
     if (namedQuery != null) {
       descriptor.addNamedQuery(namedQuery.name(), namedQuery.query());
     }

src/main/java/com/avaje/ebeaninternal/server/deploy/parse/AnnotationSql.java

@@ -14,7 +14,7 @@ public class AnnotationSql extends AnnotationParser {
 
   public void parse() {
     Class<?> cls = descriptor.getBeanType();
-    Sql sql = cls.getAnnotation(Sql.class);
+    Sql sql = AnnotationBase.findAnnotation(cls,Sql.class);
     if (sql != null) {
       descriptor.setEntityType(BeanDescriptor.EntityType.SQL);
     }

src/main/java/com/avaje/ebeaninternal/server/deploy/parse/DeployCreateProperties.java

@@ -223,7 +223,7 @@ public class DeployCreateProperties {
 
     Class<?> propertyType = field.getType();
     
-    ManyToOne manyToOne = field.getAnnotation(ManyToOne.class);
+    ManyToOne manyToOne = AnnotationBase.findAnnotation(field,ManyToOne.class);
     if (manyToOne != null){
     	Class<?> tt = manyToOne.targetEntity();
     	if (!tt.equals(void.class)){
@@ -240,7 +240,7 @@ public class DeployCreateProperties {
       // List, Set or Map based object
       Class<?> targetType = determineTargetType(field);
       if (targetType == null) {
-        Transient transAnnotation = field.getAnnotation(Transient.class);
+        Transient transAnnotation = AnnotationBase.findAnnotation(field,Transient.class);
         if (transAnnotation != null) {
           // not supporting this field (generic type used)
           return null;
@@ -298,15 +298,15 @@ public class DeployCreateProperties {
    * Return true if the field has one of the special mappings.
    */
   private boolean isSpecialScalarType(Field field) {
-    return (field.getAnnotation(DbJson.class) != null)
-        || (field.getAnnotation(DbJsonB.class) != null)
-        || (field.getAnnotation(DbArray.class) != null)
-        || (field.getAnnotation(DbHstore.class) != null);
+    return (AnnotationBase.findAnnotation(field,DbJson.class) != null)
+        || (AnnotationBase.findAnnotation(field,DbJsonB.class) != null)
+        || (AnnotationBase.findAnnotation(field,DbArray.class) != null)
+        || (AnnotationBase.findAnnotation(field,DbHstore.class) != null);
   }
   
   private boolean isTransientField(Field field) {
 
-    Transient t = field.getAnnotation(Transient.class);
+    Transient t = AnnotationBase.findAnnotation(field,Transient.class);
     return (t != null);
   }
 

src/main/java/com/avaje/ebeaninternal/server/deploy/parse/DeployInherit.java

@@ -111,11 +111,11 @@ public class DeployInherit {
       info.setParent(parent);
     }
 
-    Inheritance ia = cls.getAnnotation(Inheritance.class);
+    Inheritance ia = AnnotationBase.findAnnotation(cls,Inheritance.class);
     if (ia != null) {
       ia.strategy();
     }
-    DiscriminatorColumn da = cls.getAnnotation(DiscriminatorColumn.class);
+    DiscriminatorColumn da = AnnotationBase.findAnnotation(cls,DiscriminatorColumn.class);
     if (da != null) {
       // lowercase the discriminator column for RawSql and JSON
       info.setDiscriminatorColumn(da.name().toLowerCase());
@@ -128,7 +128,7 @@ public class DeployInherit {
       info.setDiscriminatorLength(da.length());
     }
 
-    DiscriminatorValue dv = cls.getAnnotation(DiscriminatorValue.class);
+    DiscriminatorValue dv = AnnotationBase.findAnnotation(cls,DiscriminatorValue.class);
     if (dv != null) {
       info.setDiscriminatorValue(dv.value());
     }
@@ -149,7 +149,7 @@ public class DeployInherit {
     if (cls.equals(Object.class)) {
       return false;
     }
-    Annotation a = cls.getAnnotation(Inheritance.class);
+    Annotation a = AnnotationBase.findAnnotation(cls,Inheritance.class);
     if (a != null) {
       return true;
     }