org.osgi.resource.Requirement Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of aspectjtools Show documentation

AspectJ tools most notably contains the AspectJ compiler (AJC). AJC applies aspects to Java classes during compilation, fully replacing Javac for plain Java classes and also compiling native AspectJ or annotation-based @AspectJ syntax. Furthermore, AJC can weave aspects into existing class files in a post-compile binary weaving step. This library is a superset of AspectJ weaver and hence also of AspectJ runtime.

There is a newer version: 1.9.22.1

Show newest version

/*
 * Copyright (c) OSGi Alliance (2011, 2015). All Rights Reserved.
 * 
 * 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.osgi.resource;

import java.util.Map;
import org.osgi.annotation.versioning.ConsumerType;

/**
 * A requirement that has been declared from a {@link Resource} .
 * 
 * 
 * Instances of this type must be effectively immutable. That is, for a
 * given instance of this interface, the methods defined by this interface must
 * always return the same result.
 * 
 * @ThreadSafe
 * @author $Id: 210e427134eaf0404c4f374f619af972fb570572 $
 */
@ConsumerType
public interface Requirement {
	/**
	 * Returns the namespace of this requirement.
	 * 
	 * @return The namespace of this requirement.
	 */
	String getNamespace();

	/**
	 * Returns the directives of this requirement.
	 * 
	 * @return An unmodifiable map of directive names to directive values for
	 *         this requirement, or an empty map if this requirement has no
	 *         directives.
	 */
	Map getDirectives();

	/**
	 * Returns the attributes of this requirement.
	 * 
	 * 

	 * Requirement attributes have no specified semantics and are considered
	 * extra user defined information.
	 * 
	 * @return An unmodifiable map of attribute names to attribute values for
	 *         this requirement, or an empty map if this requirement has no
	 *         attributes.
	 */
	Map getAttributes();

	/**
	 * Returns the resource declaring this requirement.
	 * 
	 * @return The resource declaring this requirement. This can be {@code null}
	 *         if this requirement is synthesized.
	 */
	Resource getResource();

	/**
	 * Compares this {@code Requirement} to another {@code Requirement}.
	 * 
	 * 
	 * This {@code Requirement} is equal to another {@code Requirement} if they
	 * have the same namespace, directives and attributes and are declared by
	 * the same resource.
	 * 
	 * @param obj The object to compare against this {@code Requirement}.
	 * @return {@code true} if this {@code Requirement} is equal to the other
	 *         object; {@code false} otherwise.
	 */
	@Override
	boolean equals(Object obj);

	/**
	 * Returns the hashCode of this {@code Requirement}.
	 * 
	 * @return The hashCode of this {@code Requirement}.
	 */
	@Override
	int hashCode();
}