/*
* $Id$
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.struts2.convention.annotation;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.annotation.ElementType;
/**
* <!-- START SNIPPET: javadoc -->
* <p>
* This annotation defines how actions can modify the namespace
* that they are added to. This overrides the behavior of the
* Convention plugin which by default uses the package names for
* namespaces. Since XWork packages are created by the Convention
* plugin via the Java packages that the actions exist in, there
* is some tricky handling of XWork parent packages and namespaces
* of the XWork packages for the Convention plugin discovered
* actions so that two actions in the same package can specify
* different parents and namespaces without collision.
* </p>
*
* <p>
* In order to handle this correctly, the name of the XWork
* package that actions are placed into is built using this
* format:
* </p>
*
* <pre>
* <java-package>#<parent-xwork-package>#<namespace>
* </pre>
*
* <p>
* This mechanism will guarantee that two actions in the same
* Java package can specify different parent packages (using the
* {@link org.apache.struts2.convention.annotation.ParentPackage} annotation)
* and namespaces (using this annotation).
* </p>
*
* <p>
* The value of a Namespace annotation should specify the portion of
* the action URL between the context path and the action name. For
* example:
* </p>
* <pre>
* @Namespace("/careers/job-postings-overview/job-postings")
* </pre>
*
* <p>
* This annotation can also be placed inside the special Java file
* named <strong>package-info.java</strong>, which allows package
* level annotations. If this is used in this manner it changes the
* default namespace for all actions within that Java package. The
* search order for the namespace of a particular class is therefore:
* </p>
*
* <ol>
* <li>If the {@link Action} annotation exists within the action and
* specifies a full URI (i.e. it starts with a / character)</li>
* <li>Any Namespace annotations placed on individual action classes</li>
* <li>Any Namespace annotations placed in the package-info.java file</li>
* <li>The namespace as determined using the Java package name and the
* standard convention based naming.</li>
* </ol>
* <!-- END SNIPPET: javadoc -->
*/
@Target({ElementType.PACKAGE, ElementType.TYPE})
@Retention(value = RetentionPolicy.RUNTIME)
public @interface Namespace {
/**
* @return The namespace value.
*/
String value();
}