DATACMNS-534 - Add support to mark a persistent property as read only.

This commit introduces @ReadOnlyProperty to mark properties as not to be persisted. That trait is exposed via the newly added PersistentProperty.isWritable() which supersedes shallBePersisted(). Currently all non-transient property that are not annotated with @ReadOnlyProperty are considered writable.

Original pull request: #88.

src/main/java/org/springframework/data/mapping/PersistentProperty.java

@@ -147,8 +147,21 @@ public interface PersistentProperty<P extends PersistentProperty<P>> {
 	 */
 	boolean isTransient();
 
+	/**
+	 * @return
+	 * @deprecated use {@link #isWritable()} instead, will be removed in 1.9 RC1.
+	 */
+	@Deprecated
 	boolean shallBePersisted();
 
+	/**
+	 * Returns whether the current property is writable, i.e. if the value held for it shall be written to the data store.
+	 * 
+	 * @return
+	 * @since 1.9
+	 */
+	boolean isWritable();
+
 	/**
 	 * Returns whether the property is an {@link Association}.
 	 * 

src/main/java/org/springframework/data/mapping/model/AbstractPersistentProperty.java

@@ -36,6 +36,7 @@ import org.springframework.util.ReflectionUtils;
  * 
  * @author Jon Brisbin
  * @author Oliver Gierke
+ * @author Christoph Strobl
  */
 public abstract class AbstractPersistentProperty<P extends PersistentProperty<P>> implements PersistentProperty<P> {
 
@@ -203,7 +204,17 @@ public abstract class AbstractPersistentProperty<P extends PersistentProperty<P>
 	 * (non-Javadoc)
 	 * @see org.springframework.data.mapping.PersistentProperty#shallBePersisted()
 	 */
+	@Override
 	public boolean shallBePersisted() {
+		return isWritable();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mapping.PersistentProperty#isWritable()
+	 */
+	@Override
+	public boolean isWritable() {
 		return !isTransient();
 	}
 
@@ -215,6 +226,10 @@ public abstract class AbstractPersistentProperty<P extends PersistentProperty<P>
 		return field == null ? false : AnnotationUtils.getAnnotation(field, Reference.class) != null;
 	}
 
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mapping.PersistentProperty#getAssociation()
+	 */
 	public Association<P> getAssociation() {
 		return association;
 	}

src/main/java/org/springframework/data/mapping/model/AnnotationBasedPersistentProperty.java

@@ -29,6 +29,7 @@ import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.data.annotation.AccessType;
 import org.springframework.data.annotation.AccessType.Type;
 import org.springframework.data.annotation.Id;
+import org.springframework.data.annotation.ReadOnlyProperty;
 import org.springframework.data.annotation.Reference;
 import org.springframework.data.annotation.Transient;
 import org.springframework.data.annotation.Version;
@@ -41,6 +42,7 @@ import org.springframework.util.Assert;
  * Special {@link PersistentProperty} that takes annotations at a property into account.
  * 
  * @author Oliver Gierke
+ * @author Christoph Strobl
  */
 public abstract class AnnotationBasedPersistentProperty<P extends PersistentProperty<P>> extends
 		AbstractPersistentProperty<P> {
@@ -169,6 +171,15 @@ public abstract class AnnotationBasedPersistentProperty<P extends PersistentProp
 		return !isTransient() && isAnnotationPresent(Reference.class);
 	}
 
+	/* 
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mapping.model.AbstractPersistentProperty#isWritable()
+	 */
+	@Override
+	public boolean isWritable() {
+		return !isTransient() && !isAnnotationPresent(ReadOnlyProperty.class);
+	}
+
 	/**
 	 * Returns the annotation found for the current {@link AnnotationBasedPersistentProperty}. Will prefer field
 	 * annotations over ones found at getters or setters.