// Copyright 2006, 2008, 2009 The Apache Software Foundation

 //

 // 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.apache.tapestry5.internal.bindings;

 import org.apache.tapestry5.PropertyConduit;

 import org.apache.tapestry5.internal.services.Invariant;

 import org.apache.tapestry5.ioc.Location;

 import org.apache.tapestry5.ioc.internal.util.TapestryException;

 import java.lang.annotation.Annotation;

 /**

  * Base class for bindings created by the {@link org.apache.tapestry5.internal.bindings.PropBindingFactory}. A subclass

  * of this is created at runtime.

  */

 public class PropBinding extends AbstractBinding

 {

     private final Object root;

     private final PropertyConduit conduit;

     private final String toString;

     private boolean invariant;

     public PropBinding(final Location location, final Object root, final PropertyConduit conduit, final String toString

     )

     {

         super(location);

         this.root = root;

         this.conduit = conduit;

         this.toString = toString;

         invariant = conduit.getAnnotation(Invariant.class) != null;

     }

     /**

      * The default implementation of get() will throw a TapestryException (binding is write only). The fabricated

      * subclass <em>may</em> override this method (as well as set()).

      */

     public Object get()

     {

         try

         {

             return conduit.get(root);

         }

         catch (Exception ex)

         {

             throw new TapestryException(ex.getMessage(), getLocation(), ex);

         }

     }

     @Override

     public void set(Object value)

     {

         try

         {

             conduit.set(root, value);

         }

         catch (Exception ex)

         {

             throw new TapestryException(ex.getMessage(), getLocation(), ex);

         }

     }

     @Override

     public String toString()

     {

         return toString;

     }

     /**

      * Almost always returns false, unless the conduit provides the {@link org.apache.tapestry5.internal.services.Invariant}

      * annotation.

      */

     @Override

     public boolean isInvariant()

     {

         return invariant;

     }

     @Override

     public Class getBindingType()

     {

         return conduit.getPropertyType();

     }

     @Override

     public <T extends Annotation> T getAnnotation(Class<T> annotationClass)

     {

         return conduit.getAnnotation(annotationClass);

     }

 }