| // Copyright 2006 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.tapestry.ioc.services;
|
|
|
| /**
|
| * Creates a "shadow" of a property of an object. The shadow has the same type as the property, and
|
| * delegates all method invocations to the property. Each method invocation on the shadow
|
| * re-acquires the value of the property from the underlying object and delegates to the current
|
| * value of the property.
|
| * <p/>
|
| * Typically, the object in question is another service, one with the "perthread" service lifecycle.
|
| * This allows a global singleton to shadow a value that is specific to the current thread (and
|
| * therefore, the current request).
|
| */
|
| public interface PropertyShadowBuilder
|
| {
|
| /**
|
| * @param <T>
|
| * @param source the object from which a property will be extracted
|
| * @param propertyName the name of a property of the object, which must be readable
|
| * @param propertyType the expected type of the property, the actual property type must be assignable to
|
| * this type
|
| * @return the shadow
|
| */
|
| <T> T build(Object source, String propertyName, Class<T> propertyType);
|
| }
|
