/*
* @(#)Modifier.java 1.27 04/02/17
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.lang.reflect;
import java.security.AccessController;
import sun.reflect.LangReflectAccess;
import sun.reflect.ReflectionFactory;
/**
* 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
* @author Kenneth Russell
*/
public
class Modifier {
/*
* Bootstrapping protocol between java.lang and java.lang.reflect
* packages
*/
static {
sun.reflect.ReflectionFactory factory =
(sun.reflect.ReflectionFactory) AccessController.doPrivileged(
new ReflectionFactory.GetReflectionFactoryAction()
);
factory.setLangReflectAccess(new java.lang.reflect.ReflectAccess());
}
/**
* Return <tt>true</tt> if the integer argument includes the
* <tt>public</tt> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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> modifier, <tt>false</tt> otherwise.
*
* @param mod a set of modifiers
* @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 modifiers
* @return a string representation of the set of modifiers
* 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;
// 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;
}
}
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