removed some unused code, improved doc

org.springframework.expression/src/main/java/org/springframework/expression/spel/reflection/ReflectionPropertyResolver.java

@@ -25,25 +25,39 @@ import org.springframework.expression.PropertyWriterExecutor;
 
 /**
  * Simple PropertyResolver that uses reflection to access properties for reading and writing. A property can be accessed
- * if it is accessible as a field on the object or through a getter (if being read) or a setter (if being written).
+ * if it is accessible as a field on the object or through a getter (if being read) or a setter (if being written). This
+ * implementation currently follows the Resolver/Executor model (it extends CacheablePropertyAccessor) - the code that
+ * would be used if it were a simple property accessor is shown at the end.
  * 
  * @author Andy Clement
  */
 public class ReflectionPropertyResolver extends CacheablePropertyAccessor {
 
-	public static boolean useResolverExecutorModel = true;
+	/**
-
+	 * @return null which means this is a general purpose accessor
-	public boolean supportsResolverExecutorModel() {
+	 */
-		return useResolverExecutorModel;
+	public Class<?>[] getSpecificTargetClasses() {
+		return null;
 	}
 
-	public PropertyReaderExecutor getReaderAccessor(EvaluationContext relatedContext, Object target, Object name) {
+	/**
+	 * Use reflection to discover if a named property is accessible on an target type and if it is return an executor
+	 * object that can be called repeatedly to retrieve that property. A property is accessible either as a field or
+	 * through a getter.
+	 * 
+	 * @param context the context in which the access is being attempted
+	 * @param target the target object on which the property is being accessed
+	 * @param name the name of the property
+	 */
+	@Override
+	public PropertyReaderExecutor getReaderAccessor(EvaluationContext context, Object target, Object name) {
 		if (target == null) {
 			return null;
 		}
 		Class<?> relevantClass = (target instanceof Class ? (Class<?>) target : target.getClass());
 		if (!(name instanceof String)) {
-			return null; // TODO should raise an exception when the property-name is not a String?
+			// A property not found exception will occur if the reflection finder was supposed to find it
+			return null;
 		}
 		String propertyName = (String) name;
 		if (relevantClass.isArray() && propertyName.equals("length")) {
@@ -60,12 +74,23 @@ public class ReflectionPropertyResolver extends CacheablePropertyAccessor {
 		return null;
 	}
 
+	/**
+	 * Use reflection to discover if a named property is accessible on an target type and if it is return an executor
+	 * object that can be called repeatedly to set that property. A property is writable either as a field or through a
+	 * setter.
+	 * 
+	 * @param context the context in which the set is being attempted
+	 * @param target the target object on which the property is being set
+	 * @param name the name of the property
+	 */
+	@Override
 	public PropertyWriterExecutor getWriterAccessor(EvaluationContext context, Object target, Object name) {
 		if (target == null) {
 			return null;
 		}
 		Class<?> relevantClass = (target instanceof Class ? (Class<?>) target : target.getClass());
 		if (!(name instanceof String)) {
+			// A property not found exception will occur if the reflection finder was supposed to find it
 			return null;
 		}
 		Field field = ReflectionUtils.findField((String) name, relevantClass);
@@ -79,16 +104,16 @@ public class ReflectionPropertyResolver extends CacheablePropertyAccessor {
 		return null;
 	}
 
-	/**
+	// /**
-	 * Return true if the resolver is able to read the specified property from the specified target.
+	// * Return true if the resolver is able to read the specified property from the specified target.
-	 */
+	// */
 	// public boolean canRead(EvaluationContext relatedContext, Object target, Object name) throws AccessException {
 	// if (target==null) {
 	// return false;
 	// }
 	// Class<?> relevantClass = (target instanceof Class ? (Class<?>) target : target.getClass());
 	// if (!(name instanceof String)) {
-//			return false; // TODO should raise an exception when the property-name is not a String?
+	// return false;
 	// }
 	// String propertyName = (String) name;
 	// Field field = ReflectionUtils.findField(propertyName, relevantClass);
@@ -101,9 +126,9 @@ public class ReflectionPropertyResolver extends CacheablePropertyAccessor {
 	// }
 	// return false;
 	// }
-
+	//
-	/**
+	// /**
-	 * Read the specified property from the specified target.
+	// * Read the specified property from the specified target. //
 	// */
 	// public Object read(EvaluationContext context, Object target, Object name) throws AccessException {
 	// if (target==null) {
@@ -111,7 +136,7 @@ public class ReflectionPropertyResolver extends CacheablePropertyAccessor {
 	// }
 	// Class<?> relevantClass = (target instanceof Class ? (Class<?>) target : target.getClass());
 	// if (!(name instanceof String)) {
-//			return null; // TODO should raise an exception if the property cannot be found?
+	// return null;
 	// }
 	// String propertyName = (String) name;
 	// Field field = ReflectionUtils.findField(propertyName, relevantClass);
@@ -143,8 +168,8 @@ public class ReflectionPropertyResolver extends CacheablePropertyAccessor {
 	// }
 	// return null;
 	// }
-
+	// public void write(EvaluationContext context, Object target, Object name, Object newValue) throws AccessException
-//	public void write(EvaluationContext context, Object target, Object name, Object newValue) throws AccessException {
+	// {
 	// if (target==null) {
 	// return;
 	// }
@@ -178,11 +203,8 @@ public class ReflectionPropertyResolver extends CacheablePropertyAccessor {
 	// }
 	// }
 	// }
-
+	//
-	public Class<?>[] getSpecificTargetClasses() {
+	//
-		return null; // this is a general purpose resolver that will try to access properties on any type!
-	}
-
 	// public boolean canWrite(EvaluationContext context, Object target, Object name) throws AccessException {
 	// if (target==null) {
 	// return false;
@@ -198,5 +220,4 @@ public class ReflectionPropertyResolver extends CacheablePropertyAccessor {
 	// return true;
 	// return false;
 	// }
-
 }