/* * @(#)Modifier.java 1.24 06/10/10 * * Copyright 1990-2008 Sun Microsystems, Inc. All Rights Reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER * * This program 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. * * This program 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 at /legal/license.txt). * * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa * Clara, CA 95054 or visit www.sun.com if you need additional * information or have any questions. * */ package java.lang.reflect; /** * The Modifier class provides <code>static</code> 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 <a * href="http://java.sun.com/docs/books/vmspec/2nd-edition/html/VMSpecTOC.doc.html"><i>The * Java</i><sup><small>TM</small></sup> <i>Virtual Machine Specification, Second * edition</i></a> tables * <a href="http://java.sun.com/docs/books/vmspec/2nd-edition/html/ClassFile.doc.html#75734">4.1</a>, * <a href="http://java.sun.com/docs/books/vmspec/2nd-edition/html/ClassFile.doc.html#88358">4.4</a>, * <a href="http://java.sun.com/docs/books/vmspec/2nd-edition/html/ClassFile.doc.html#75568">4.5</a>, and * <a href="http://java.sun.com/docs/books/vmspec/2nd-edition/html/ClassFile.doc.html#88478">4.7</a>. * * @see Class#getModifiers() * @see Member#getModifiers() * * @author Nakul Saraiya */ public class Modifier { /** * Return <tt>true</tt> if the integer argument includes the * <tt>public</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>public</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isPublic(int mod) { return (mod & PUBLIC) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>private</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>private</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isPrivate(int mod) { return (mod & PRIVATE) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>protected</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>protected</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isProtected(int mod) { return (mod & PROTECTED) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>static</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>static</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isStatic(int mod) { return (mod & STATIC) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>final</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>final</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isFinal(int mod) { return (mod & FINAL) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>synchronized</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>synchronized</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isSynchronized(int mod) { return (mod & SYNCHRONIZED) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>volatile</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>volatile</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isVolatile(int mod) { return (mod & VOLATILE) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>transient</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>transient</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isTransient(int mod) { return (mod & TRANSIENT) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>native</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>native</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isNative(int mod) { return (mod & NATIVE) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>interface</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>interface</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isInterface(int mod) { return (mod & INTERFACE) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>abstract</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>abstract</tt> modifier; <tt>false</tt> otherwise. */ public static boolean isAbstract(int mod) { return (mod & ABSTRACT) != 0; } /** * Return <tt>true</tt> if the integer argument includes the * <tt>strictfp</tt> modifer, <tt>false</tt> otherwise. * * @param mod a set of modifers * @return <tt>true</tt> if <code>mod</code> includes the * <tt>strictfp</tt> modifier; <tt>false</tt> 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 <a * href="http://java.sun.com/docs/books/jls/second_edition/html/j.title.doc.html"><em>The * Java Language Specification, Second Edition</em></a> sections * <a href="http://java.sun.com/docs/books/jls/second_edition/html/classes.doc.html#21613">§8.1.1</a>, * <a href="http://java.sun.com/docs/books/jls/second_edition/html/classes.doc.html#78091">§8.3.1</a>, * <a href="http://java.sun.com/docs/books/jls/second_edition/html/classes.doc.html#78188">§8.4.3</a>, * <a href="http://java.sun.com/docs/books/jls/second_edition/html/classes.doc.html#42018">§8.8.3</a>, and * <a href="http://java.sun.com/docs/books/jls/second_edition/html/interfaces.doc.html#235947">§9.1.1</a>. * The full modifier ordering used by this method is: * <blockquote> <code> * public protected private abstract static final transient * volatile synchronized native strictfp * interface </code> </blockquote> * The <code>interface</code> 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. * * @param mod a set of modifers * @return a string representation of the set of modifers * represented by <code>mod</code> */ 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 <em>The Java Virtual * Machine Specification, Second Edition</em>, tables 4.1, 4.4, * 4.5, and 4.7. */ /** * The <code>int</code> value representing the <code>public</code> * modifier. */ public static final int PUBLIC = 0x00000001; /** * The <code>int</code> value representing the <code>private</code> * modifier. */ public static final int PRIVATE = 0x00000002; /** * The <code>int</code> value representing the <code>protected</code> * modifier. */ public static final int PROTECTED = 0x00000004; /** * The <code>int</code> value representing the <code>static</code> * modifier. */ public static final int STATIC = 0x00000008; /** * The <code>int</code> value representing the <code>final</code> * modifier. */ public static final int FINAL = 0x00000010; /** * The <code>int</code> value representing the <code>synchronized</code> * modifier. */ public static final int SYNCHRONIZED = 0x00000020; /** * The <code>int</code> value representing the <code>volatile</code> * modifier. */ public static final int VOLATILE = 0x00000040; /** * The <code>int</code> value representing the <code>transient</code> * modifier. */ public static final int TRANSIENT = 0x00000080; /** * The <code>int</code> value representing the <code>native</code> * modifier. */ public static final int NATIVE = 0x00000100; /** * The <code>int</code> value representing the <code>interface</code> * modifier. */ public static final int INTERFACE = 0x00000200; /** * The <code>int</code> value representing the <code>abstract</code> * modifier. */ public static final int ABSTRACT = 0x00000400; /** * The <code>int</code> value representing the <code>strictfp</code> * modifier. */ public static final int STRICT = 0x00000800; }