001// Copyright 2005 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry.annotations;
016
017import java.lang.annotation.Documented;
018import java.lang.annotation.ElementType;
019import java.lang.annotation.Retention;
020import java.lang.annotation.RetentionPolicy;
021import java.lang.annotation.Target;
022
023/**
024 * Annotation used to <em>define</em> new managed beans, including limited/lightweight
025 * initialization. For complex initialiation, the XML specification is necessary.
026 * <p>
027 * One of the advantages is that, on the XML side, it is always necessary to provide complete class
028 * names; here on the Java/annotation side, we can leverage imports.
029 * <p>
030 * The managed bean will have a name that matches the property name; this allows such a bean to be
031 * referenced via the "bean:" binding prefix, or via
032 * {@link org.apache.tapestry.IComponent#getBeans()}.
033 * <p>
034 * This annotation adds a new {@link org.apache.tapestry.spec.IBeanSpecification} to the
035 * {@link org.apache.tapestry.spec.IComponentSpecification}.
036 * 
037 * @author Howard M. Lewis Ship
038 * @since 4.0
039 */
040
041@Target(
042{ ElementType.METHOD })
043@Retention(RetentionPolicy.RUNTIME)
044@Documented
045public @interface Bean {
046    /**
047     * The Java class to instantiate. The default is Object.class; if a non-default value is
048     * specified, that will be the class to instantiate; otherwise, the bean class will be
049     * determined from the property type. Generally, this annotation is only used when the property
050     * type is an interface (or abstract base class).
051     */
052
053    Class value() default Object.class;
054
055    /**
056     * Optional initializer string for the bean, as <em>lightweight initialization</em> (a list of
057     * properties and values).
058     */
059
060    String initializer() default "";
061
062    /**
063     * The lifecycle of the bean, defaults to Lifecycle.REQUEST.
064     * 
065     * @see BeanLifecycle
066     */
067
068    Lifecycle lifecycle() default Lifecycle.REQUEST;
069}