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	/*
	* Copyright (c) 1996, 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.reflect;

	import java.security.AccessController;
	import sun.reflect.LangReflectAccess;
	import sun.reflect.ReflectionFactory;

	/**
	* The Modifier class provides {@code static} methods and
	* constants to decode class and member access modifiers. The sets of
	* modifiers are represented as integers with distinct bit positions
	* representing different modifiers. The values for the constants
	* representing the modifiers are taken from the tables in sections 4.1, 4.4, 4.5, and 4.7 of
	* <cite>The Java™ Virtual Machine Specification</cite>.
	*
	* @see Class#getModifiers()
	* @see Member#getModifiers()
	*
	* @author Nakul Saraiya
	* @author Kenneth Russell
	*/
	public class Modifier {

	/*
	* Bootstrapping protocol between java.lang and java.lang.reflect
	* packages
	*/
	static {
	sun.reflect.ReflectionFactory factory =
	AccessController.doPrivileged(
	new ReflectionFactory.GetReflectionFactoryAction());
	factory.setLangReflectAccess(new java.lang.reflect.ReflectAccess());
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code public} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code public} modifier; {@code false} otherwise.
	*/
	public static boolean isPublic(int mod) {
	return (mod & PUBLIC) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code private} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code private} modifier; {@code false} otherwise.
	*/
	public static boolean isPrivate(int mod) {
	return (mod & PRIVATE) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code protected} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code protected} modifier; {@code false} otherwise.
	*/
	public static boolean isProtected(int mod) {
	return (mod & PROTECTED) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code static} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code static} modifier; {@code false} otherwise.
	*/
	public static boolean isStatic(int mod) {
	return (mod & STATIC) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code final} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code final} modifier; {@code false} otherwise.
	*/
	public static boolean isFinal(int mod) {
	return (mod & FINAL) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code synchronized} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code synchronized} modifier; {@code false} otherwise.
	*/
	public static boolean isSynchronized(int mod) {
	return (mod & SYNCHRONIZED) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code volatile} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code volatile} modifier; {@code false} otherwise.
	*/
	public static boolean isVolatile(int mod) {
	return (mod & VOLATILE) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code transient} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code transient} modifier; {@code false} otherwise.
	*/
	public static boolean isTransient(int mod) {
	return (mod & TRANSIENT) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code native} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code native} modifier; {@code false} otherwise.
	*/
	public static boolean isNative(int mod) {
	return (mod & NATIVE) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code interface} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code interface} modifier; {@code false} otherwise.
	*/
	public static boolean isInterface(int mod) {
	return (mod & INTERFACE) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code abstract} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code abstract} modifier; {@code false} otherwise.
	*/
	public static boolean isAbstract(int mod) {
	return (mod & ABSTRACT) != 0;
	}

	/**
	* Return {@code true} if the integer argument includes the
	* {@code strictfp} modifier, {@code false} otherwise.
	*
	* @param mod a set of modifiers
	* @return {@code true} if {@code mod} includes the
	* {@code strictfp} modifier; {@code false} otherwise.
	*/
	public static boolean isStrict(int mod) {
	return (mod & STRICT) != 0;
	}

	/**
	* Return a string describing the access modifier flags in
	* the specified modifier. For example:
	* <blockquote><pre>
	* public final synchronized strictfp
	* </pre></blockquote>
	* The modifier names are returned in an order consistent with the
	* suggested modifier orderings given in sections 8.1.1, 8.3.1, 8.4.3, 8.8.3, and 9.1.1 of
	* <cite>The Java™ Language Specification</cite>.
	* The full modifier ordering used by this method is:
	* <blockquote> {@code
	* public protected private abstract static final transient
	* volatile synchronized native strictfp
	* interface } </blockquote>
	* The {@code interface} modifier discussed in this class is
	* not a true modifier in the Java language and it appears after
	* all other modifiers listed by this method. This method may
	* return a string of modifiers that are not valid modifiers of a
	* Java entity; in other words, no checking is done on the
	* possible validity of the combination of modifiers represented
	* by the input.
	*
	* Note that to perform such checking for a known kind of entity,
	* such as a constructor or method, first AND the argument of
	* {@code toString} with the appropriate mask from a method like
	* {@link #constructorModifiers} or {@link #methodModifiers}.
	*
	* @param mod a set of modifiers
	* @return a string representation of the set of modifiers
	* represented by {@code mod}
	*/
	public static String toString(int mod) {
	StringBuilder sb = new StringBuilder();
	int len;

	if ((mod & PUBLIC) != 0) sb.append("public ");
	if ((mod & PROTECTED) != 0) sb.append("protected ");
	if ((mod & PRIVATE) != 0) sb.append("private ");

	/* Canonical order */
	if ((mod & ABSTRACT) != 0) sb.append("abstract ");
	if ((mod & STATIC) != 0) sb.append("static ");
	if ((mod & FINAL) != 0) sb.append("final ");
	if ((mod & TRANSIENT) != 0) sb.append("transient ");
	if ((mod & VOLATILE) != 0) sb.append("volatile ");
	if ((mod & SYNCHRONIZED) != 0) sb.append("synchronized ");
	if ((mod & NATIVE) != 0) sb.append("native ");
	if ((mod & STRICT) != 0) sb.append("strictfp ");
	if ((mod & INTERFACE) != 0) sb.append("interface ");

	if ((len = sb.length()) > 0) /* trim trailing space */
	return sb.toString().substring(0, len-1);
	return "";
	}

	/*
	* Access modifier flag constants from tables 4.1, 4.4, 4.5, and 4.7 of
	* <cite>The Java™ Virtual Machine Specification</cite>
	*/

	/**
	* The {@code int} value representing the {@code public}
	* modifier.
	*/
	public static final int PUBLIC = 0x00000001;

	/**
	* The {@code int} value representing the {@code private}
	* modifier.
	*/
	public static final int PRIVATE = 0x00000002;

	/**
	* The {@code int} value representing the {@code protected}
	* modifier.
	*/
	public static final int PROTECTED = 0x00000004;

	/**
	* The {@code int} value representing the {@code static}
	* modifier.
	*/
	public static final int STATIC = 0x00000008;

	/**
	* The {@code int} value representing the {@code final}
	* modifier.
	*/
	public static final int FINAL = 0x00000010;

	/**
	* The {@code int} value representing the {@code synchronized}
	* modifier.
	*/
	public static final int SYNCHRONIZED = 0x00000020;

	/**
	* The {@code int} value representing the {@code volatile}
	* modifier.
	*/
	public static final int VOLATILE = 0x00000040;

	/**
	* The {@code int} value representing the {@code transient}
	* modifier.
	*/
	public static final int TRANSIENT = 0x00000080;

	/**
	* The {@code int} value representing the {@code native}
	* modifier.
	*/
	public static final int NATIVE = 0x00000100;

	/**
	* The {@code int} value representing the {@code interface}
	* modifier.
	*/
	public static final int INTERFACE = 0x00000200;

	/**
	* The {@code int} value representing the {@code abstract}
	* modifier.
	*/
	public static final int ABSTRACT = 0x00000400;

	/**
	* The {@code int} value representing the {@code strictfp}
	* modifier.
	*/
	public static final int STRICT = 0x00000800;

	// Bits not (yet) exposed in the public API either because they
	// have different meanings for fields and methods and there is no
	// way to distinguish between the two in this class, or because
	// they are not Java programming language keywords
	static final int BRIDGE = 0x00000040;
	static final int VARARGS = 0x00000080;
	static final int SYNTHETIC = 0x00001000;
	static final int ANNOTATION = 0x00002000;
	static final int ENUM = 0x00004000;
	static final int MANDATED = 0x00008000;
	static boolean isSynthetic(int mod) {
	return (mod & SYNTHETIC) != 0;
	}

	static boolean isMandated(int mod) {
	return (mod & MANDATED) != 0;
	}

	// Note on the FOO_MODIFIERS fields and fooModifiers() methods:
	// the sets of modifiers are not guaranteed to be constants
	// across time and Java SE releases. Therefore, it would not be
	// appropriate to expose an external interface to this information
	// that would allow the values to be treated as Java-level
	// constants since the values could be constant folded and updates
	// to the sets of modifiers missed. Thus, the fooModifiers()
	// methods return an unchanging values for a given release, but a
	// value that can potentially change over time.

	/**
	* The Java source modifiers that can be applied to a class.
	* @jls 8.1.1 Class Modifiers
	*/
	private static final int CLASS_MODIFIERS =
	Modifier.PUBLIC \| Modifier.PROTECTED \| Modifier.PRIVATE \|
	Modifier.ABSTRACT \| Modifier.STATIC \| Modifier.FINAL \|
	Modifier.STRICT;

	/**
	* The Java source modifiers that can be applied to an interface.
	* @jls 9.1.1 Interface Modifiers
	*/
	private static final int INTERFACE_MODIFIERS =
	Modifier.PUBLIC \| Modifier.PROTECTED \| Modifier.PRIVATE \|
	Modifier.ABSTRACT \| Modifier.STATIC \| Modifier.STRICT;


	/**
	* The Java source modifiers that can be applied to a constructor.
	* @jls 8.8.3 Constructor Modifiers
	*/
	private static final int CONSTRUCTOR_MODIFIERS =
	Modifier.PUBLIC \| Modifier.PROTECTED \| Modifier.PRIVATE;

	/**
	* The Java source modifiers that can be applied to a method.
	* @jls8.4.3 Method Modifiers
	*/
	private static final int METHOD_MODIFIERS =
	Modifier.PUBLIC \| Modifier.PROTECTED \| Modifier.PRIVATE \|
	Modifier.ABSTRACT \| Modifier.STATIC \| Modifier.FINAL \|
	Modifier.SYNCHRONIZED \| Modifier.NATIVE \| Modifier.STRICT;

	/**
	* The Java source modifiers that can be applied to a field.
	* @jls 8.3.1 Field Modifiers
	*/
	private static final int FIELD_MODIFIERS =
	Modifier.PUBLIC \| Modifier.PROTECTED \| Modifier.PRIVATE \|
	Modifier.STATIC \| Modifier.FINAL \| Modifier.TRANSIENT \|
	Modifier.VOLATILE;

	/**
	* The Java source modifiers that can be applied to a method or constructor parameter.
	* @jls 8.4.1 Formal Parameters
	*/
	private static final int PARAMETER_MODIFIERS =
	Modifier.FINAL;

	/**
	*
	*/
	static final int ACCESS_MODIFIERS =
	Modifier.PUBLIC \| Modifier.PROTECTED \| Modifier.PRIVATE;

	/**
	* Return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to a class.
	* @return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to a class.
	*
	* @jls 8.1.1 Class Modifiers
	* @since 1.7
	*/
	public static int classModifiers() {
	return CLASS_MODIFIERS;
	}

	/**
	* Return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to an interface.
	* @return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to an interface.
	*
	* @jls 9.1.1 Interface Modifiers
	* @since 1.7
	*/
	public static int interfaceModifiers() {
	return INTERFACE_MODIFIERS;
	}

	/**
	* Return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to a constructor.
	* @return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to a constructor.
	*
	* @jls 8.8.3 Constructor Modifiers
	* @since 1.7
	*/
	public static int constructorModifiers() {
	return CONSTRUCTOR_MODIFIERS;
	}

	/**
	* Return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to a method.
	* @return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to a method.
	*
	* @jls 8.4.3 Method Modifiers
	* @since 1.7
	*/
	public static int methodModifiers() {
	return METHOD_MODIFIERS;
	}

	/**
	* Return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to a field.
	* @return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to a field.
	*
	* @jls 8.3.1 Field Modifiers
	* @since 1.7
	*/
	public static int fieldModifiers() {
	return FIELD_MODIFIERS;
	}

	/**
	* Return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to a parameter.
	* @return an {@code int} value OR-ing together the source language
	* modifiers that can be applied to a parameter.
	*
	* @jls 8.4.1 Formal Parameters
	* @since 1.8
	*/
	public static int parameterModifiers() {
	return PARAMETER_MODIFIERS;
	}
	}

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