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	/*
	* Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.lang.annotation;

	/**
	* The common interface extended by all annotation types. Note that an
	* interface that manually extends this one does <i>not</i> define
	* an annotation type. Also note that this interface does not itself
	* define an annotation type.
	*
	* More information about annotation types can be found in section 9.6 of
	* <cite>The Java™ Language Specification</cite>.
	*
	* The {@link java.lang.reflect.AnnotatedElement} interface discusses
	* compatibility concerns when evolving an annotation type from being
	* non-repeatable to being repeatable.
	*
	* @author Josh Bloch
	* @since 1.5
	*/
	public interface Annotation {
	/**
	* Returns true if the specified object represents an annotation
	* that is logically equivalent to this one. In other words,
	* returns true if the specified object is an instance of the same
	* annotation type as this instance, all of whose members are equal
	* to the corresponding member of this annotation, as defined below:
	* <ul>
	* <li>Two corresponding primitive typed members whose values are
	* <tt>x</tt> and <tt>y</tt> are considered equal if <tt>x == y</tt>,
	* unless their type is <tt>float</tt> or <tt>double</tt>.
	*
	* <li>Two corresponding <tt>float</tt> members whose values
	* are <tt>x</tt> and <tt>y</tt> are considered equal if
	* <tt>Float.valueOf(x).equals(Float.valueOf(y))</tt>.
	* (Unlike the <tt>==</tt> operator, NaN is considered equal
	* to itself, and <tt>0.0f</tt> unequal to <tt>-0.0f</tt>.)
	*
	* <li>Two corresponding <tt>double</tt> members whose values
	* are <tt>x</tt> and <tt>y</tt> are considered equal if
	* <tt>Double.valueOf(x).equals(Double.valueOf(y))</tt>.
	* (Unlike the <tt>==</tt> operator, NaN is considered equal
	* to itself, and <tt>0.0</tt> unequal to <tt>-0.0</tt>.)
	*
	* <li>Two corresponding <tt>String</tt>, <tt>Class</tt>, enum, or
	* annotation typed members whose values are <tt>x</tt> and <tt>y</tt>
	* are considered equal if <tt>x.equals(y)</tt>. (Note that this
	* definition is recursive for annotation typed members.)
	*
	* <li>Two corresponding array typed members <tt>x</tt> and <tt>y</tt>
	* are considered equal if <tt>Arrays.equals(x, y)</tt>, for the
	* appropriate overloading of {@link java.util.Arrays#equals}.
	* </ul>
	*
	* @return true if the specified object represents an annotation
	* that is logically equivalent to this one, otherwise false
	*/
	boolean equals(Object obj);

	/**
	* Returns the hash code of this annotation, as defined below:
	*
	* <p>The hash code of an annotation is the sum of the hash codes
	* of its members (including those with default values), as defined
	* below:
	*
	* The hash code of an annotation member is (127 times the hash code
	* of the member-name as computed by {@link String#hashCode()}) XOR
	* the hash code of the member-value, as defined below:
	*
	* <p>The hash code of a member-value depends on its type:
	* <ul>
	* <li>The hash code of a primitive value <tt><i>v</i></tt> is equal to
	* <tt><i>WrapperType</i>.valueOf(<i>v</i>).hashCode()</tt>, where
	* <tt><i>WrapperType</i></tt> is the wrapper type corresponding
	* to the primitive type of <tt><i>v</i></tt> ({@link Byte},
	* {@link Character}, {@link Double}, {@link Float}, {@link Integer},
	* {@link Long}, {@link Short}, or {@link Boolean}).
	*
	* <li>The hash code of a string, enum, class, or annotation member-value
	I <tt><i>v</i></tt> is computed as by calling
	* <tt><i>v</i>.hashCode()</tt>. (In the case of annotation
	* member values, this is a recursive definition.)
	*
	* <li>The hash code of an array member-value is computed by calling
	* the appropriate overloading of
	* {@link java.util.Arrays#hashCode(long[]) Arrays.hashCode}
	* on the value. (There is one overloading for each primitive
	* type, and one for object reference types.)
	* </ul>
	*
	* @return the hash code of this annotation
	*/
	int hashCode();

	/**
	* Returns a string representation of this annotation. The details
	* of the representation are implementation-dependent, but the following
	* may be regarded as typical:
	* <pre>
	* @com.acme.util.Name(first=Alfred, middle=E., last=Neuman)
	* </pre>
	*
	* @return a string representation of this annotation
	*/
	String toString();

	/**
	* Returns the annotation type of this annotation.
	* @return the annotation type of this annotation
	*/
	Class<? extends Annotation> annotationType();
	}

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