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  * 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

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 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&trade; 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&trade; 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) {

         StringBuffer sb = new StringBuffer();

         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&trade; 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 boolean isSynthetic(int mod) {

       return (mod & SYNTHETIC) != 0;

     }

     /**

      * See JLSv3 section 8.1.1.

      */

     private static final int CLASS_MODIFIERS =

         Modifier.PUBLIC         | Modifier.PROTECTED    | Modifier.PRIVATE |

         Modifier.ABSTRACT       | Modifier.STATIC       | Modifier.FINAL   |

         Modifier.STRICT;

     /**

      * See JLSv3 section 9.1.1.

      */

     private static final int INTERFACE_MODIFIERS =

         Modifier.PUBLIC         | Modifier.PROTECTED    | Modifier.PRIVATE |

         Modifier.ABSTRACT       | Modifier.STATIC       | Modifier.STRICT;

     /**

      * See JLSv3 section 8.8.3.

      */

     private static final int CONSTRUCTOR_MODIFIERS =

         Modifier.PUBLIC         | Modifier.PROTECTED    | Modifier.PRIVATE;

     /**

      * See JLSv3 section 8.4.3.

      */

     private static final int METHOD_MODIFIERS =

         Modifier.PUBLIC         | Modifier.PROTECTED    | Modifier.PRIVATE |

         Modifier.ABSTRACT       | Modifier.STATIC       | Modifier.FINAL   |

         Modifier.SYNCHRONIZED   | Modifier.NATIVE       | Modifier.STRICT;

     /**

      * See JLSv3 section 8.3.1.

      */

     private static final int FIELD_MODIFIERS =

         Modifier.PUBLIC         | Modifier.PROTECTED    | Modifier.PRIVATE |

         Modifier.STATIC         | Modifier.FINAL        | Modifier.TRANSIENT |

         Modifier.VOLATILE;

     /**

      * 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 inteface.

      *

      * @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;

     }

 }