/*
* The MIT License
*
* Copyright (c) 2004-2010, Sun Microsystems, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package hudson;
import jenkins.YesNoMaybe;
import net.java.sezpoz.Indexable;
import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import static java.lang.annotation.ElementType.*;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
import static jenkins.YesNoMaybe.MAYBE;
/**
* Marks a field, a method, or a class for automatic discovery, so that Hudson can locate
* implementations of {@link ExtensionPoint}s automatically.
*
* <p>
* (In contrast, in earlier Hudson, the registration was manual.)
*
* <p>
* In a simplest case, put this on your class, and Hudson will create an instance of it
* and register it to the appropriate {@link ExtensionList}.
*
* <p>
* If you'd like Hudson to call
* a factory method instead of a constructor, put this annotation on your static factory
* method. Hudson will invoke it and if the method returns a non-null instance, it'll be
* registered. The return type of the method is used to determine which {@link ExtensionList}
* will get the instance.
*
* Finally, you can put this annotation on a static field if the field contains a reference
* to an instance that you'd like to register.
*
* <p>
* This is the default way of having your implementations auto-registered to Hudson,
* but Hudson also supports arbitrary DI containers for hosting your implementations.
* See {@link ExtensionFinder} for more details.
*
* @author Kohsuke Kawaguchi
* @since 1.286
* @see <a href="http://sezpoz.java.net/">SezPoz</a>
* @see ExtensionFinder
* @see ExtensionList
*/
@Indexable
@Retention(RUNTIME)
@Target({TYPE, FIELD, METHOD})
@Documented
public @interface Extension {
/**
* Used for sorting extensions.
*
* Extensions will be sorted in the descending order of the ordinal.
* This is a rather poor approach to the problem, so its use is generally discouraged.
*
* @since 1.306
*/
double ordinal() default 0;
/**
* If an extension is optional, don't log any class loading errors when reading it.
* @since 1.358
*/
boolean optional() default false;
/**
* Marks whether this extension works with dynamic loading of a plugin.
*
* <p>
* "Yes" indicates an explicit sign-off from the developer indicating this component supports that.
* Similarly, "No" indicates that this extension is known not to support it, which forces Jenkins
* not to offer dynamic loading as an option.
*
* <p>
* The "MayBe" value indicates that there's no such explicit sign-off. So the dynamic loading may or may not
* work.
*
* <p>
* If your plugin contains any extension that has dynamic loadability set to NO, then Jenkins
* will prompt the user to restart Jenkins to have the plugin take effect. If every component
* is marked as YES, then Jenkins will simply dynamic load the plugin without asking the user.
* Otherwise, Jenkins will ask the user if he wants to restart, or go ahead and dynamically deploy.
*
* @since 1.442
*/
YesNoMaybe dynamicLoadable() default MAYBE;
}