/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited

  *

  * Licensed under the Apache License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  *     http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 package org.acegisecurity.intercept.method;

 import org.acegisecurity.ConfigAttribute;

 import org.acegisecurity.ConfigAttributeDefinition;

 import org.springframework.metadata.Attributes;

 import java.lang.reflect.Method;

 import java.util.Collection;

 import java.util.Iterator;

 /**

  * Stores a {@link ConfigAttributeDefinition} for each method signature defined by Commons Attributes.<P>This class

  * will only detect those attributes which are defined for:

  *  <ul>

  *      <li>The class-wide attributes defined for the intercepted class.</li>

  *      <li>The class-wide attributes defined for interfaces explicitly implemented by the intercepted class.</li>

  *      <li>The method-specific attributes defined for the intercepted method of the intercepted class.</li>

  *      <li>The method-specific attributes defined by any explicitly implemented interface if that interface

  *      contains a method signature matching that of the intercepted method.</li>

  *  </ul>

  *  </p>

  *  <P>Note that attributes defined against parent classes (either for their methods or interfaces) are not

  * detected. The attributes must be defined against an explicit method or interface on the intercepted class.</p>

  *  <p>Attributes detected that do not implement {@link ConfigAttribute} will be ignored.</p>

  *

  * @author Cameron Braid

  * @author Ben Alex

  * @version $Id: MethodDefinitionAttributes.java 1784 2007-02-24 21:00:24Z luke_t $

  */

 public class MethodDefinitionAttributes extends AbstractMethodDefinitionSource {

     //~ Instance fields ================================================================================================

     private Attributes attributes;

     //~ Methods ========================================================================================================

     private void add(ConfigAttributeDefinition definition, Collection attribs) {

         for (Iterator iter = attribs.iterator(); iter.hasNext();) {

             Object o = (Object) iter.next();

             if (o instanceof ConfigAttribute) {

                 definition.addConfigAttribute((ConfigAttribute) o);

             }

         }

     }

     private void addClassAttributes(ConfigAttributeDefinition definition, Class clazz) {

         addClassAttributes(definition, new Class[] {clazz});

     }

     private void addClassAttributes(ConfigAttributeDefinition definition, Class[] clazz) {

         for (int i = 0; i < clazz.length; i++) {

             Collection classAttributes = attributes.getAttributes(clazz[i]);

             if (classAttributes != null) {

                 add(definition, classAttributes);

             }

         }

     }

     private void addInterfaceMethodAttributes(ConfigAttributeDefinition definition, Method method) {

         Class[] interfaces = method.getDeclaringClass().getInterfaces();

         for (int i = 0; i < interfaces.length; i++) {

             Class clazz = interfaces[i];

             try {

                 Method m = clazz.getDeclaredMethod(method.getName(), (Class[]) method.getParameterTypes());

                 addMethodAttributes(definition, m);

             } catch (Exception e) {

                 // this won't happen since we are getting a method from an interface that

                 // the declaring class implements

             }

         }

     }

     private void addMethodAttributes(ConfigAttributeDefinition definition, Method method) {

         // add the method level attributes

         Collection methodAttributes = attributes.getAttributes(method);

         if (methodAttributes != null) {

             add(definition, methodAttributes);

         }

     }

     public Iterator getConfigAttributeDefinitions() {

         return null;

     }

     protected ConfigAttributeDefinition lookupAttributes(Method method) {

         ConfigAttributeDefinition definition = new ConfigAttributeDefinition();

         Class interceptedClass = method.getDeclaringClass();

         // add the class level attributes for the implementing class

         addClassAttributes(definition, interceptedClass);

         // add the class level attributes for the implemented interfaces

         addClassAttributes(definition, interceptedClass.getInterfaces());

         // add the method level attributes for the implemented method

         addMethodAttributes(definition, method);

         // add the method level attributes for the implemented intreface methods

         addInterfaceMethodAttributes(definition, method);

         if (definition.size() == 0) {

             return null;

         } else {

             return definition;

         }

     }

     public void setAttributes(Attributes attributes) {

         this.attributes = attributes;

     }

 }