docs/manual/usage.html

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<title>ProGuard Usage</title>
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<h2>Usage</h2>

To run ProGuard, just type:
<p class="code">
<code><b>java -jar proguard.jar </b></code><i>options</i> ...
</p>
You can find the ProGuard jar in the <code>lib</code> directory of the
ProGuard distribution. Options can also be put in one or more configuration
files. Typically, you'll put most options in a configuration file (say,
<code>myconfig.pro</code>), and just call:
<p class="code">
<code><b>java -jar proguard.jar @myconfig.pro</b></code>
</p>
You can combine command line options and options from configuration files, for
instance:
<p class="code">
<code><b>java -jar proguard.jar @myconfig.pro -verbose</b></code>
</p>
<p>
In a configuration file, a <code><b>#</b></code> sign and all remaining
characters on that line are ignored, allowing you to add comments.
<p>
Extra whitespace between words and delimiters is ignored. To specify file
names with spaces or special characters, words can be quoted with single or
double quotes. Note that the quotes may need to be escaped when used on the
command line, to avoid them being gobbled by the shell.
<p>
Options can be grouped arbitrarily in arguments on the command line and in
lines in configuration files. This means that you can quote any arbitrary
section of command line options, to avoid shell expansion of special
characters, for instance.
<p>
The order of the options is generally irrelevant. They can be abbreviated to
their first unique characters.
<p>

The sections below provide more details:
<ul>
<li><a href="#iooptions">Input/Output Options</a>
<li><a href="#keepoptions">Keep Options</a>
<li><a href="#shrinkingoptions">Shrinking Options</a>
<li><a href="#optimizationoptions">Optimization Options</a>
<li><a href="#obfuscationoptions">Obfuscation Options</a>
<li><a href="#preverificationoptions">Preverification Options</a>
<li><a href="#generaloptions">General Options</a>
<li><a href="#classpath">Class Paths</a>
<li><a href="#filename">File Names</a>
<li><a href="#filefilters">File Filters</a>
<li><a href="#filters">Filters</a>
<li><a href="#keepoverview">Overview of <code>Keep</code> Options</a>
<li><a href="#keepoptionmodifiers">Keep Option Modifiers</a>
<li><a href="#classspecification">Class Specifications</a>
</ul>

<a name="iooptions">&nbsp;</a>
<h2>Input/Output Options</h2>

<dl>
<dt><a name="at"><code><b>@</b></code></a><a href="#filename"><i>filename</i></a></dt>

<dd>Short for '<a href="#include"><code>-include</code></a>
     <a href="#filename"><i>filename</i></a>'.</dd>

<dt><a name="include"><code><b>-include</b></code></a>
    <a href="#filename"><i>filename</i></a></dt>

<dd>Recursively reads configuration options from the given file
    <i>filename</i>.</dd>

<dt><a name="basedirectory"><code><b>-basedirectory</b></code></a>
    <a href="#filename"><i>directoryname</i></a></dt>

<dd>Specifies the base directory for all subsequent relative file names in
    these configuration arguments or this configuration file.</dd>

<dt><a name="injars"><code><b>-injars</b></code></a>
    <a href="#classpath"><i>class_path</i></a></dt>

<dd>Specifies the input jars (or wars, ears, zips, or directories) of the
    application to be processed. The class files in these jars will be
    processed and written to the output jars. By default, any non-class files
    will be copied without changes. Please be aware of any temporary files
    (e.g. created by IDEs), especially if you are reading your input files
    straight from directories. The entries in the class path can be filtered,
    as explained in the <a href="#filefilters">filters</a> section. For better
    readability, class path entries can be specified using multiple
    <code>-injars</code> options.</dd>

<dt><a name="outjars"><code><b>-outjars</b></code></a>
    <a href="#classpath"><i>class_path</i></a></dt>

<dd>Specifies the names of the output jars (or wars, ears, zips, or
    directories). The processed input of the preceding <code>-injars</code>
    options will be written to the named jars. This allows you to collect the
    contents of groups of input jars into corresponding groups of output jars.
    In addition, the output entries can be filtered, as explained in
    the <a href="#filefilters">filters</a> section. Each processed class file
    or resource file is then written to the first output entry with a matching
    filter, within the group of output jars.
    <p>
    You must avoid letting the output files overwrite any input files. For
    better readability, class path entries can be specified using multiple
    <code>-outjars</code> options. Without any <code>-outjars</code> options,
    no jars will be written.</dd>

<dt><a name="libraryjars"><code><b>-libraryjars</b></code></a>
    <a href="#classpath"><i>class_path</i></a></dt>

<dd>Specifies the library jars (or wars, ears, zips, or directories) of the
    application to be processed. The files in these jars will not be included
    in the output jars. The specified library jars should at least contain the
    class files that are <i>extended</i> by application class files. Library
    class files that are only <i>called</i> needn't be present, although their
    presence can improve the results of the optimization step. The entries in
    the class path can be filtered, as explained in the <a
    href="#filefilters">filters</a> section. For better readability, class path
    entries can be specified using multiple <code>-libraryjars</code> options.
    <p>
    Please note that the boot path and the class path set for running ProGuard
    are not considered when looking for library classes. This means that you
    explicitly have to specify the run-time jar that your code will use.
    Although this may seem cumbersome, it allows you to process applications
    targeted at different run-time environments. For example, you can process
    <a href="examples.html#application">J2SE applications</a> as well as <a
    href="examples.html#midlet">JME midlets</a>, just by specifying the
    appropriate run-time jar.</dd>

<dt><a name="dontskipnonpubliclibraryclasses"><code><b>-dontskipnonpubliclibraryclasses</b></code></a></dt>

<dd>Specifies not to ignore non-public library classes. By default, non-public
    library classes are skipped while parsing library jars. The classes are
    typically not relevant during processing, since they don't affect the
    actual program code in the input jars. Ignoring them reduces memory usage
    and processing time. Occasionally, a badly designed library may contain a
    non-public library class that is extended/implemented by a public library
    class. If the latter library class in turn is extended/implemented by a
    program class, ProGuard will complain that it can't find the non-public
    library class, which it had ignored during parsing. This option will
    overcome that problem, at the cost of greater memory usage and longer
    processing time.</dd>

<dt><a name="dontskipnonpubliclibraryclassmembers"><code><b>-dontskipnonpubliclibraryclassmembers</b></code></a></dt>

<dd>Specifies not to ignore package visible library class members (fields and
    methods). By default, these class members are skipped while parsing
    library classes, as program classes will generally not refer to them.
    Sometimes however, program classes reside in the same packages as library
    classes, and they do refer to their package visible class members. In
    those cases, it can be useful to actually read the class members, in order
    to make sure the processed code remains consistent.</dd>

<dt><a name="keepdirectories"><code><b>-keepdirectories</b></code></a>
    [<i><a href="#filefilters">directory_filter</a></i>]</dt>

<dd>Specifies the directories to be kept in the output jars (or wars, ears, or
    directories). By default, directory entries are removed. This reduces the
    jar size, but it may be undesirable if the program code tries to find them
    with constructs like "<code>MyClass.class.getResource("")</code>". If the
    option is specified without a filter, all directories are kept. With a
    filter, only matching directories are kept.</dd>

<dt><a name="target"><code><b>-target</b></code></a> <i>version</i></dt>

<dd>Specifies the version number to be set in the processed class files. The
    version number can be one of <code>1.0</code>, <code>1.1</code>,
    <code>1.2</code>, <code>1.3</code>, <code>1.4</code>, <code>1.5</code> (or
    just <code>5</code>), or <code>1.6</code> (or just <code>6</code>). By
    default, the version numbers of the class files are left unchanged. For
    example, you may want to <a href="examples.html#upgrade">upgrade class
    files to Java 6</a>, by changing their version numbers and having them
    preverified.</dd>

<dt><a name="forceprocessing"><code><b>-forceprocessing</b></code></a></dt>

<dd>Specifies to process the input, even if the output seems up to date. The
    up-to-dateness test is based on a comparison of the date stamps of the
    specified input, output, and configuration files or directories.</dd>

</dl>
<p>

<a name="keepoptions">&nbsp;</a>
<h2>Keep Options</h2>

<dl>
<dt><a name="keep"><code><b>-keep</b></code></a>
    [<a href="#keepoptionmodifiers">,<i>modifier</i></a>,...]
    <a href="#classspecification"><i>class_specification</i></a></dt>

<dd>Specifies classes and class members (fields and methods) to be preserved
    as entry points to your code. For example, in order to <a
    href="examples.html#application">keep an application</a>, you can specify
    the main class along with its main method. In order to <a
    href="examples.html#library">process a library</a>, you should specify all
    publicly accessible elements.</dd>

<dt><a name="keepclassmembers"><code><b>-keepclassmembers</b></code></a>
    [<a href="#keepoptionmodifiers">,<i>modifier</i></a>,...]
    <a href="#classspecification"><i>class_specification</i></a></dt>

<dd>Specifies class members to be preserved, if their classes are preserved as
    well. For example, you may want to <a
    href="examples.html#serializable">keep all serialization fields and
    methods</a> of classes that implement the <code>Serializable</code>
    interface.</dd>

<dt><a name="keepclasseswithmembers"><code><b>-keepclasseswithmembers</b></code></a>
    [<a href="#keepoptionmodifiers">,<i>modifier</i></a>,...]
    <a href="#classspecification"><i>class_specification</i></a></dt>

<dd>Specifies classes and class members to be preserved, on the condition that
    all of the specified class members are present. For example, you may want
    to <a href="examples.html#applications">keep all applications</a> that
    have a main method, without having to list them explicitly.</dd>

<dt><a name="keepnames"><code><b>-keepnames</b></code></a>
    <a href="#classspecification"><i>class_specification</i></a></dt>

<dd>Short for <a href="#keep"><code>-keep</code></a>,<a href="#allowshrinking"><code>allowshrinking</code></a>
    <a href="#classspecification"><i>class_specification</i></a>
    <p>
    Specifies classes and class members whose names are to be preserved, if
    they aren't removed in the shrinking phase. For example, you may want to
    <a href="examples.html#serializable">keep all class names</a> of classes
    that implement the <code>Serializable</code> interface, so that the
    processed code remains compatible with any originally serialized classes.
    Classes that aren't used at all can still be removed. Only applicable when
    obfuscating.</dd>

<dt><a name="keepclassmembernames"><code><b>-keepclassmembernames</b></code></a>
    <a href="#classspecification"><i>class_specification</i></a></dt>

<dd>Short for <a href="#keepclassmembers"><code>-keepclassmembers</code></a>,<a href="#allowshrinking"><code>allowshrinking</code></a>
    <a href="#classspecification"><i>class_specification</i></a>
    <p>
    Specifies class members whose names are to be preserved, if they aren't
    removed in the shrinking phase. For example, you may want to preserve the
    name of the synthetic <code>class$</code> methods when <a
    href="examples.html#library">processing a library</a>, so obfuscators can
    detect it again when processing an application that uses the processed
    library (although ProGuard itself doesn't need this). Only applicable when
    obfuscating.</dd>

<dt><a name="keepclasseswithmembernames"><code><b>-keepclasseswithmembernames</b></code></a>
    <a href="#classspecification"><i>class_specification</i></a></dt>

<dd>Short for <a href="#keepclasseswithmembers"><code>-keepclasseswithmembers</code></a>,<a href="#allowshrinking"><code>allowshrinking</code></a>
    <a href="#classspecification"><i>class_specification</i></a>
    <p>
    Specifies classes and class members whose names are to be preserved, on
    the condition that all of the specified class members are present after
    the shrinking phase. For example, you may want to <a
    href="examples.html#native">keep all native method names</a> and the names
    of their classes, so that the processed code can still link with the
    native library code. Native methods that aren't used at all can still be
    removed. If a class file is used, but none of its native methods are, its
    name will still be obfuscated. Only applicable when obfuscating.</dd>

<dt><a name="printseeds"><code><b>-printseeds</b></code></a>
    [<a href="#filename"><i>filename</i></a>]</dt>

<dd>Specifies to exhaustively list classes and class members matched by the
    various <code>-keep</code> options. The list is printed to the standard
    output or to the given file. The list can be useful to verify if the
    intended class members are really found, especially if you're using
    wildcards. For example, you may want to list all the <a
    href="examples.html#applications">applications</a> or all the <a
    href="examples.html#applets">applets</a> that you are keeping.</dd>

</dl>
<p>

<a name="shrinkingoptions">&nbsp;</a>
<h2>Shrinking Options</h2>

<dl>
<dt><a name="dontshrink"><code><b>-dontshrink</b></code></a></dt>

<dd>Specifies not to shrink the input class files. By default, shrinking is
    applied; all classes and class members are removed, except for the ones
    listed by the various <code>-keep</code> options, and the ones on which
    they depend, directly or indirectly. A shrinking step is also applied
    after each optimization step, since some optimizations may open the
    possibility to remove more classes and class members.</dd>

<dt><a name="printusage"><code><b>-printusage</b></code></a>
    [<a href="#filename"><i>filename</i></a>]</dt>

<dd>Specifies to list dead code of the input class files. The list is printed
    to the standard output or to the given file. For example, you can <a
    href="examples.html#deadcode">list the unused code of an application</a>.
    Only applicable when shrinking.</dd>

<dt><a name="whyareyoukeeping"><code><b>-whyareyoukeeping</b></code></a>
    <a href="#classspecification"><i>class_specification</i></a></dt>

<dd>Specifies to print details on why the given classes and class members are
    being kept in the shrinking step. This can be useful if you are wondering
    why some given element is present in the output. In general, there can be
    many different reasons. This option prints the shortest chain of methods
    to a specified seed or entry point, for each specified class and class
    member. <i>In the current implementation, the shortest chain that is
    printed out may sometimes contain circular deductions -- these do not
    reflect the actual shrinking process.</i> If the <a
    href="#verbose"><code>-verbose</code></a> option if specified, the traces
    include full field and method signatures. Only applicable when
    shrinking.</dd>

</dl>
<p>

<a name="optimizationoptions">&nbsp;</a>
<h2>Optimization Options</h2>

<dl>
<dt><a name="dontoptimize"><code><b>-dontoptimize</b></code></a></dt>

<dd>Specifies not to optimize the input class files. By default, optimization
    is enabled; all methods are optimized at a bytecode level.</dd>

<dt><a name="optimizations"><code><b>-optimizations</b></code></a>
    <a href="optimizations.html"><i>optimization_filter</i></a></dt>

<dd>Specifies the optimizations to be enabled and disabled, at a more
    fine-grained level. Only applicable when optimizing. <i>This is an expert
    option.</i></dd>

<dt><a name="optimizationpasses"><code><b>-optimizationpasses</b></code></a> <i>n</i></dt>

<dd>Specifies the number of optimization passes to be performed. By default, a
    single pass is performed. Multiple passes may result in further
    improvements. If no improvements are found after an optimization pass, the
    optimization is ended. Only applicable when optimizing.</dd>

<dt><a name="assumenosideeffects"><code><b>-assumenosideeffects</b></code></a>
    <a href="#classspecification"><i>class_specification</i></a></dt>

<dd>Specifies methods that don't have any side effects (other than maybe
    returning a value). In the optimization step, ProGuard will then remove
    calls to such methods, if it can determine that the return values aren't
    used. Note that ProGuard will analyze your program code to find such
    methods automatically. It will not analyze library code, for which this
    option can thus be useful. For example, you could specify the method
    <code>System.currentTimeMillis()</code>, so that any idle calls to it will
    be removed. Note that ProGuard applies the option to the entire hierarchy
    of the specified methods. Only applicable when optimizing. In general,
    making assumptions can be dangerous; you can easily break the processed
    code. <i>Only use this option if you know what you're doing!</i></dd>

<dt><a name="allowaccessmodification"><code><b>-allowaccessmodification</b></code></a></dt>

<dd>Specifies that the access modifiers of classes and class members may be
    broadened during processing. This can improve the results of the
    optimization step. For instance, when inlining a public getter, it may be
    necessary to make the accessed field public too. Although Java's binary
    compatibility specifications formally do not require this (cfr. <a href=
    "http://java.sun.com/docs/books/jls/second_edition/html/j.title.doc.html"
    >The Java Language Specification, Second Edition</a>, <a href=
    "http://java.sun.com/docs/books/jls/second_edition/html/binaryComp.doc.html#47259"
    >Section 13.4.6</a>), some virtual machines would have problems with the
    processed code otherwise. Only applicable when optimizing (and when
    obfuscating with the <a
    href="#repackageclasses"><code>-repackageclasses</code></a> option).
    <p>
    <i>Counter-indication:</i> you probably shouldn't use this option when
    processing code that is to be used as a library, since classes and class
    members that weren't designed to be public in the API may become
    public.</dd>

<dt><a name="mergeinterfacesaggressively"><code><b>-mergeinterfacesaggressively</b></code></a></dt>

<dd>Specifies that interfaces may be merged, even if their implementing
    classes don't implement all interface methods. This can reduce the size of
    the output by reducing the total number of classes. Note that Java's
    binary compatibility specifications allow such constructs (cfr. <a href=
    "http://java.sun.com/docs/books/jls/second_edition/html/j.title.doc.html"
    >The Java Language Specification, Second Edition</a>, <a href=
    "http://java.sun.com/docs/books/jls/second_edition/html/binaryComp.doc.html#45347"
    >Section 13.5.3</a>), even if they are not allowed in the Java language
    (cfr. <a href=
    "http://java.sun.com/docs/books/jls/second_edition/html/j.title.doc.html"
    >The Java Language Specification, Second Edition</a>, <a href=
    "http://java.sun.com/docs/books/jls/second_edition/html/classes.doc.html#34031"
    >Section 8.1.4</a>). Only applicable when optimizing.
    <p>
    <i>Counter-indication:</i> setting this option can reduce the performance
    of the processed code on some JVMs, since advanced just-in-time
    compilation tends to favor more interfaces with fewer implementing
    classes. Worse, some JVMs may not be able to handle the resulting code.
    Notably:
    <ul>
    <li>Sun's JRE 1.3 may throw an <code>InternalError</code> when
        encountering more than 256 <i>Miranda</i> methods (interface methods
        without implementations) in a class.
    </ul></dd>

</dl>
<p>

<a name="obfuscationoptions">&nbsp;</a>
<h2>Obfuscation Options</h2>

<dl>
<dt><a name="dontobfuscate"><code><b>-dontobfuscate</b></code></a></dt>

<dd>Specifies not to obfuscate the input class files. By default, obfuscation
    is applied; classes and class members receive new short random names,
    except for the ones listed by the various <code>-keep</code> options.
    Internal attributes that are useful for debugging, such as source files
    names, variable names, and line numbers are removed.</dd>

<dt><a name="printmapping"><code><b>-printmapping</b></code></a>
    [<a href="#filename"><i>filename</i></a>]</dt>

<dd>Specifies to print the mapping from old names to new names for classes and
    class members that have been renamed. The mapping is printed to the
    standard output or to the given file. For example, it is required for
    subsequent <a href="examples.html#incremental">incremental
    obfuscation</a>, or if you ever want to make sense again of <a
    href="examples.html#stacktrace">obfuscated stack traces</a>. Only
    applicable when obfuscating.</dd>

<dt><a name="applymapping"><code><b>-applymapping</b></code></a>
    <a href="#filename"><i>filename</i></a></dt>

<dd>Specifies to reuse the given name mapping that was printed out in a
    previous obfuscation run of ProGuard. Classes and class members that are
    listed in the mapping file receive the names specified along with them.
    Classes and class members that are not mentioned receive new names. The
    mapping may refer to input classes as well as library classes. This option
    can be useful for <a href="examples.html#incremental">incremental
    obfuscation</a>, i.e. processing add-ons or small patches to an existing
    piece of code. In such cases, you should consider whether you also need
    the option <a
    href="#useuniqueclassmembernames"><code>-useuniqueclassmembernames</code></a>.
    Only applicable when obfuscating.</dd>

<dt><a name="obfuscationdictionary"><code><b>-obfuscationdictionary</b></code></a>
    <a href="#filename"><i>filename</i></a></dt>

<dd>Specifies a text file from which all valid words are used as obfuscated
    field and method names. By default, short names like 'a', 'b', etc. are
    used as obfuscated names. With an obfuscation dictionary, you can specify
    a list of reserved key words, or identifiers with foreign characters, for
    instance. White space, punctuation characters, duplicate words, and
    comments after a <code><b>#</b></code> sign are ignored. Note that an
    obfuscation dictionary hardly improves the obfuscation. Decent compilers
    can automatically replace them, and the effect can fairly simply be undone
    by obfuscating again with simpler names. The most useful application is
    specifying strings that are typically already present in class files (such
    as 'Code'), thus reducing the class file sizes just a little bit more.
    Only applicable when obfuscating.</dd>

<dt><a name="classobfuscationdictionary"><code><b>-classobfuscationdictionary</b></code></a>
    <a href="#filename"><i>filename</i></a></dt>

<dd>Specifies a text file from which all valid words are used as obfuscated
    class names. The obfuscation dictionary is similar to the one of the
    option <a
    href="#obfuscationdictionary"><code>-obfuscationdictionary</code></a>.
    Only applicable when obfuscating.</dd>

<dt><a name="packageobfuscationdictionary"><code><b>-packageobfuscationdictionary</b></code></a>
    <a href="#filename"><i>filename</i></a></dt>

<dd>Specifies a text file from which all valid words are used as obfuscated
    package names. The obfuscation dictionary is similar to the one of the
    option <a
    href="#obfuscationdictionary"><code>-obfuscationdictionary</code></a>.
    Only applicable when obfuscating.</dd>

<dt><a name="overloadaggressively"><code><b>-overloadaggressively</b></code></a></dt>

<dd>Specifies to apply aggressive overloading while obfuscating. Multiple
    fields and methods can then get the same names, as long as their arguments
    and return types are different (not just their arguments). This option can
    make the processed code even smaller (and less comprehensible). Only
    applicable when obfuscating.
    <p>
    <i>Counter-indication:</i> the resulting class files fall within the Java
    bytecode specification (cfr. <a href=
    "http://java.sun.com/docs/books/vmspec/2nd-edition/html/VMSpecTOC.doc.html"
    >The Java Virtual Machine Specification, Second Edition</a>, first
    paragraphs of <a href=
    "http://java.sun.com/docs/books/vmspec/2nd-edition/html/ClassFile.doc.html#2877"
    >Section 4.5</a> and <a href=
    "http://java.sun.com/docs/books/vmspec/2nd-edition/html/ClassFile.doc.html#1513"
    >Section 4.6</a>), even though this kind of overloading is not allowed in
    the Java language (cfr. <a href=
    "http://java.sun.com/docs/books/jls/second_edition/html/j.title.doc.html"
    >The Java Language Specification, Second Edition</a>, <a href=
    "http://java.sun.com/docs/books/jls/second_edition/html/classes.doc.html#40898"
    >Section 8.3</a> and <a href=
    "http://java.sun.com/docs/books/jls/second_edition/html/classes.doc.html#227768"
    >Section 8.4.7</a>). Still, some tools have problems with it. Notably:
    <ul>
    <li>Sun's JDK 1.2.2 <code>javac</code> compiler produces an exception when
        compiling with such a library (cfr. <a href=
        "http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4216736">Bug
        #4216736</a>). You probably shouldn't use this option for processing
        libraries.
    <li>Sun's JRE 1.4 and later fail to serialize objects with overloaded
        primitive fields.
    <li>Sun's JRE 1.5 <code>pack200</code> tool reportedly has problems with
        overloaded class members.
    </ul></dd>

<dt><a name="useuniqueclassmembernames"><code><b>-useuniqueclassmembernames</b></code></a></dt>

<dd>Specifies to assign the same obfuscated names to class members that have
    the same names, and different obfuscated names to class members that have
    different names (for each given class member signature). Without the
    option, more class members can be mapped to the same short names like 'a',
    'b', etc. The option therefore increases the size of the resulting code
    slightly, but it ensures that the saved obfuscation name mapping can
    always be respected in subsequent incremental obfuscation steps.
    <p>
    For instance, consider two distinct interfaces containing methods with the
    same name and signature. Without this option, these methods may get
    different obfuscated names in a first obfuscation step. If a patch is then
    added containing a class that implements both interfaces, ProGuard will
    have to enforce the same method name for both methods in an incremental
    obfuscation step. The original obfuscated code is changed, in order to
    keep the resulting code consistent. With this option <i>in the initial
    obfuscation step</i>, such renaming will never be necessary.
    <p>
    This option is only applicable when obfuscating. In fact, if you are
    planning on performing incremental obfuscation, you probably want to avoid
    shrinking and optimization altogether, since these steps could remove or
    modify parts of your code that are essential for later additions.</dd>

<dt><a name="dontusemixedcaseclassnames"><code><b>-dontusemixedcaseclassnames</b></code></a></dt>

<dd>Specifies not to generate mixed-case class names while obfuscating. By
    default, obfuscated class names can contain a mix of upper-case characters
    and lower-case characters. This creates perfectly acceptable and usable
    jars. Only if a jar is unpacked on a platform with a case-insensitive
    filing system (say, Windows), the unpacking tool may let similarly named
    class files overwrite each other. Code that self-destructs when it's
    unpacked! Developers who really want to unpack their jars on Windows can
    use this option to switch off this behavior. Note that the obfuscated jars
    will become larger as a result. Only applicable when obfuscating.</dd>

<dt><a name="keeppackagenames"><code><b>-keeppackagenames</b></code></a>
    [<i><a href="#filters">package_filter</a></i>]</dt>

<dd>Specifies not obfuscate the given package names. The optional filter is a
    comma-separated list of package names. Package names can contain <b>?</b>,
    <b>*</b>, and <b>**</b> wildcards, and they can be preceded by the
    <b>!</b> negator. Only applicable when obfuscating.</dd>

<dt><a name="flattenpackagehierarchy"><code><b>-flattenpackagehierarchy</b></code></a>
    [<i>package_name</i>]</dt>

<dd>Specifies to repackage all packages that are renamed, by moving them into
    the single given parent package. Without argument or with an empty string
    (''), the packages are moved into the root package. This option is one
    example of further <a href="examples.html#repackaging">obfuscating package
    names</a>. It can make the processed code smaller and less comprehensible.
    Only applicable when obfuscating.</dd>

<dt><a name="repackageclasses"><code><b>-repackageclasses</b></code></a>
    [<i>package_name</i>]</dt>

<dd>Specifies to repackage all class files that are renamed, by moving them
    into the single given package. Without argument or with an empty string
    (''), the package is removed completely. This option option overrides the
    <a
    href="#flattenpackagehierarchy"><code>-flattenpackagehierarchy</code></a>
    option. It is another example of further <a
    href="examples.html#repackaging">obfuscating package names</a>. It can
    make the processed code even smaller and less comprehensible. Its
    deprecated name is <code>-defaultpackage</code>. Only applicable when
    obfuscating.
    <p>
    <i>Counter-indication:</i> classes that look for resource files in their
    package directories will no longer work properly if they are moved
    elsewhere. When in doubt, just leave the packaging untouched by not using
    this option.</dd>

<dt><a name="keepattributes"><code><b>-keepattributes</b></code></a>
    [<i><a href="#filters">attribute_filter</a></i>]</dt>

<dd>Specifies any optional attributes to be preserved. The attributes can be
    specified with one or more <code>-keepattributes</code> directives. The
    optional filter is a comma-separated list of attribute names. Attribute
    names can contain <b>?</b>, <b>*</b>, and <b>**</b> wildcards, and they
    can be preceded by the <b>!</b> negator. Typical optional attributes are
    <code>Exceptions</code>, <code>Signature</code>, <code>Deprecated</code>,
    <code>SourceFile</code>, <code>SourceDir</code>,
    <code>LineNumberTable</code>, <code>LocalVariableTable</code>,
    <code>LocalVariableTypeTable</code>, <code>Synthetic</code>,
    <code>EnclosingMethod</code>, <code>RuntimeVisibleAnnotations</code>,
    <code>RuntimeInvisibleAnnotations</code>,
    <code>RuntimeVisibleParameterAnnotations</code>,
    <code>RuntimeInvisibleParameterAnnotations</code>, and
    <code>AnnotationDefault</code>. The <code>InnerClasses</code> attribute
    name can be specified as well, referring to the source name part of this
    attribute. For example, you should at least keep the
    <code>Exceptions</code>, <code>InnerClasses</code>, and
    <code>Signature</code> attributes when <a
    href="examples.html#library">processing a library</a>. As another example,
    you should keep the <code>SourceFile</code> and
    <code>LineNumberTable</code> attributes for <a
    href="examples.html#stacktrace">producing useful obfuscated stack
    traces</a>. Only applicable when obfuscating.</dd>

<dt><a name="renamesourcefileattribute"><code><b>-renamesourcefileattribute</b></code></a>
    [<i>string</i>]</dt>

<dd>Specifies a constant string to be put in the <code>SourceFile</code>
    attributes (and <code>SourceDir</code> attributes) of the class files.
    Note that the attribute has to be present to start with, so it also has to
    be preserved explicitly using the <code>-keepattributes</code> directive.
    For example, you may want to have your processed libraries and
    applications produce <a href="examples.html#stacktrace">useful obfuscated
    stack traces</a>. Only applicable when obfuscating.</dd>

<dt><a name="adaptclassstrings"><code><b>-adaptclassstrings</b></code></a>
    [<i><a href="#filters">class_filter</a></i>]</dt>

<dd>Specifies that string constants that correspond to class names should be
    obfuscated as well. Without a filter, all string constants that correspond
    to class names are adapted. With a filter, only string constants in
    classes that match the filter are adapted. For example, if your code
    contains a large number of hard-coded strings that refer to classes, and
    you prefer not to keep their names, you may want to use this option.
    Primarily applicable when obfuscating, although corresponding classes are
    automatically kept in the shrinking step too.</dd>

<dt><a name="adaptresourcefilenames"><code><b>-adaptresourcefilenames</b></code></a>
    [<i><a href="#filefilters">file_filter</a></i>]</dt>

<dd>Specifies the resource files to be renamed, based on the obfuscated names
    of the corresponding class files (if any). Without a filter, all resource
    files that correspond to class files are renamed. With a filter, only
    matching files are renamed. For example, see <a
    href="examples.html#resourcefiles">processing resource files</a>. Only
    applicable when obfuscating.</dd>

<dt><a name="adaptresourcefilecontents"><code><b>-adaptresourcefilecontents</b></code></a>
    [<i><a href="#filefilters">file_filter</a></i>]</dt>

<dd>Specifies the resource files whose contents are to be updated. Any class
    names mentioned in the resource files are renamed, based on the obfuscated
    names of the corresponding classes (if any). Without a filter, the
    contents of all resource files updated. With a filter, only matching files
    are updated. The resource files are parsed and written using the
    platform's default character set. You can change this default character set
    by setting the environment variable <code>LANG</code> or the Java system
    property <code>file.encoding</code>. For an example,
    see <a href="examples.html#resourcefiles">processing resource files</a>.
    Only applicable when obfuscating.</dd>

</dl>
<p>

<a name="preverificationoptions">&nbsp;</a>
<h2>Preverification Options</h2>

<dl>
<dt><a name="dontpreverify"><code><b>-dontpreverify</b></code></a></dt>

<dd>Specifies not to preverify the processed class files. By default, class
    files are preverified if they are targeted at Java Micro Edition or at
    Java 6 or higher. For Java Micro Edition, preverification is required, so
    you will need to run an external preverifier on the processed code if you
    specify this option. For Java 6, preverification is not required (yet),
    but it improves the efficiency of the class loading in the Java Virtual
    Machine.</dd>

<dt><a name="microedition"><code><b>-microedition</b></code></a></dt>

<dd>Specifies that the processed class files are targeted at Java Micro
    Edition. The preverifier will then add the appropriate StackMap
    attributes, which are different from the default StackMapTable attributes
    for Java Standard Edition. For example, you will need this option if you
    are <a href="examples.html#midlets">processing midlets</a>.</dd>

</dl>
<p>

<a name="generaloptions">&nbsp;</a>
<h2>General Options</h2>

<dl>
<dt><a name="verbose"><code><b>-verbose</b></code></a></dt>

<dd>Specifies to write out some more information during processing. If the
    program terminates with an exception, this option will print out the entire
    stack trace, instead of just the exception message.</dd>

<dt><a name="dontnote"><code><b>-dontnote</b></code></a>
    [<i><a href="#filters">class_filter</a></i>]</dt>

<dd>Specifies not to print notes about potential mistakes or omissions in the
    configuration, like typos in class names, or like missing options that
    might be useful. The optional filter is a regular expression; ProGuard
    doesn't print notes about classes with matching names.</dd>

<dt><a name="dontwarn"><code><b>-dontwarn</b></code></a>
    [<i><a href="#filters">class_filter</a></i>]</dt>

<dd>Specifies not to warn about unresolved references and other important
    problems at all. The optional filter is a regular expression; ProGuard
    doesn't print warnings about classes with matching names. Ignoring
    warnings can be dangerous. For instance, if the unresolved classes or
    class members are indeed required for processing, the processed code will
    not function properly. <i>Only use this option if you know what you're
    doing!</i></dd>

<dt><a name="ignorewarnings"><code><b>-ignorewarnings</b></code></a></dt>

<dd>Specifies to print any warnings about unresolved references and other
    important problems, but to continue processing in any case. Ignoring
    warnings can be dangerous. For instance, if the unresolved classes or
    class members are indeed required for processing, the processed code will
    not function properly. <i>Only use this option if you know what you're
    doing!</i></dd>

<dt><a name="printconfiguration"><code><b>-printconfiguration</b></code></a>
    [<a href="#filename"><i>filename</i></a>]</dt>

<dd>Specifies to write out the entire configuration that has been parsed, with
    included files and replaced variables. The structure is printed to the
    standard output or to the given file. This can sometimes be useful for
    debugging configurations, or for converting XML configurations into a more
    readable format.</dd>

<dt><a name="dump"><code><b>-dump</b></code></a>
    [<a href="#filename"><i>filename</i></a>]</dt>

<dd>Specifies to write out the internal structure of the class files, after
    any processing. The structure is printed to the standard output or to the
    given file. For example, you may want to <a
    href="examples.html#structure">write out the contents of a given jar
    file</a>, without processing it at all.</dd>

</dl>
<p>

<a name="classpath">&nbsp;</a>
<h2>Class Paths</h2>

ProGuard accepts a generalization of class paths to specify input files and
output files. A class path consists of entries, separated by the traditional
path separator (e.g. '<b>:</b>' on Unix, or '<b>;</b>' on Windows platforms).
The order of the entries determines their priorities, in case of duplicates.
<p>
Each input entry can be:
<ul>
<li>A class file or resource file.
<li>A jar file, containing any of the above,
<li>A war file, containing any of the above,
<li>An ear file, containing any of the above,
<li>A zip file, containing any of the above,
<li>A directory (structure), containing any of the above.
</ul>
<p>
The paths of directly specified class files and resource files is ignored, so
class files should generally be part of a jar file, a war file, an ear file, a
zip file, or a directory. In addition, the paths of class files should not have
any additional directory prefixes inside the archives or directories.

<p>
Each output entry can be:
<ul>
<li>A jar file, in which all processed class files and resource files will be
    collected.
<li>A war file, in which any and all of the above will be collected,
<li>An ear file, in which any and all of the above will be collected,
<li>A zip file, in which any and all of the above will be collected,
<li>A directory, in which any and all of the above will be collected.
</ul>
<p>
When writing output entries, ProGuard will generally package the results in a
sensible way, reconstructing the input entries as much as required. Writing
everything to an output directory is the most straightforward option: the
output directory will contain a complete reconstruction of the input entries.
The packaging can be almost arbitrarily complex though: you could process an
entire application, packaged in a zip file along with its documentation,
writing it out as a zip file again. The Examples section shows a few ways
to <a href="examples.html#restructuring">restructure output archives</a>.
<p>
Files and directories can be specified as discussed in the section on <a
href="#filename">file names</a> below.
<p>
In addition, ProGuard provides the possibility to filter the class path
entries and their contents, based on their full relative file names. Each
class path entry can be followed by up to 5 types of <a
href="#filefilters">file filters</a> between parentheses, separated by
semi-colons:
<ul>
<li>A filter for all zip names that are encountered,
<li>A filter for all ear names that are encountered,
<li>A filter for all war names that are encountered,
<li>A filter for all jar names that are encountered,
<li>A filter for all class file names and resource file names that are
    encountered.
</ul>
<p>
If fewer than 5 filters are specified, they are assumed to be the latter
filters. Any empty filters are ignored. More formally, a filtered class path
entry looks like this:
<pre>
<i>classpathentry</i><b>(</b>[[[[<i>zipfilter</i><b>;</b>]<i>earfilter</i><b>;</b>]<i>warfilter</i><b>;</b>]<i>jarfilter</i><b>;</b>]<i>filefilter</i><b>)</b>
</pre>
<p>
Square brackets "[]" mean that their contents are optional.
<p>
For example, "<code>rt.jar(java/**.class,javax/**.class)</code>" matches all
class files in the <code>java</code> and <code>javax</code> directories inside
the <code>rt</code> jar.
<p>
For example, "<code>input.jar(!**.gif,images/**)</code>" matches all files in
the <code>images</code> directory inside the <code>input</code> jar, except
gif files.
<p>
Note that the different filters are applied to all corresponding file types,
irrespective of their nesting levels in the input; they are orthogonal.
<p>
For example,
"<code>input.war(lib/**.jar,support/**.jar;**.class,**.gif)</code>" only
considers jar files in the <code>lib</code> and <code>support</code>
directories in the <code>input</code> war, not any other jar files. It then
matches all class files and gif files that are encountered.
<p>
The filters allow for an almost infinite number of packaging and repackaging
possibilities. The Examples section provides a few more examples
for <a href="examples.html#filtering">filtering input and output</a>.
<p>

<a name="filename">&nbsp;</a>
<h2>File Names</h2>

ProGuard accepts absolute paths and relative paths for the various file names
and directory names. A relative path is interpreted as follows:
<ul>
<li>relative to the base directory, if set, or otherwise
<li>relative to the configuration file in which it is specified, if any, or
    otherwise
<li>relative to the working directory.
</ul>
<p>
The names can contain Java system properties delimited by '<b>&lt;</b>' and
'<b>&gt;</b>'. The system properties
are automatically replaced by their respective values.
<p>
For example, <code>&lt;java.home&gt;/lib/rt.jar</code> will automatically be
expanded to something like <code>/usr/local/java/jdk/jre/lib/rt.jar</code>.
Similarly, <code>&lt;user.home&gt;</code> will be expanded to the user's home
directory, and <code>&lt;user.dir&gt;</code> will be expanded to the current
working directory.
<p>
Names with special characters like spaces and parentheses must be quoted with
single or double quotes. Note that each file name in a list of names has to be
quoted individually. Also note that the quotes themselves may need to be
escaped when used on the command line, to avoid them being gobbled by the
shell.
<p>
For example, on the command line, you could use an option like <code>'-injars
"my program.jar":"/your directory/your program.jar"'</code>.
<p>

<a name="filefilters">&nbsp;</a>
<h2>File Filters</h2>

Like general <a href="#filters">filters</a>, a file filter is a
comma-separated list of file names that can contain wildcards. Only files with
matching file names are read (in the case of input jars), or written (in the
case of output jars). The following wildcards are supported:

<table cellspacing="10">
<tr><td valign="top"><code><b>?</b></code></td>
    <td>matches any single character in a file name.</td></tr>
<tr><td valign="top"><code><b>*</b></code></td>
    <td>matches any part of a filename not containing the directory
        separator.</td></tr>
<tr><td valign="top"><code><b>**</b></code></td>
    <td>matches any part of a filename, possibly containing any number of
        directory separators.</td></tr>
</table>

For example, "<code>java/**.class,javax/**.class</code>" matches all
class files in the <code>java</code> and <code>javax</code>.
<p>

Furthermore, a file name can be preceded by an exclamation mark '<b>!</b>' to
<i>exclude</i> the file name from further attempts to match with
<i>subsequent</i> file names.
<p>
For example, "<code>!**.gif,images/**</code>" matches all files in the
<code>images</code> directory, except gif files.
<p>
The Examples section provides a few more examples for <a
href="examples.html#filtering">filtering input and output</a>.

<a name="filters">&nbsp;</a>
<h2>Filters</h2>

ProGuard offers options with filters for many different aspects of the
configuration: names of files, directories, classes, packages, attributes,
optimizations, etc.
<p>
A filter is a list of comma-separated names that can contain wildcards. Only
names that match an item on the list pass the filter. The supported wildcards
depend on the type of names for which the filter is being used, but the
following wildcards are typical:

<table cellspacing="10">
<tr><td valign="top"><code><b>?</b></code></td>
    <td>matches any single character in a name.</td></tr>
<tr><td valign="top"><code><b>*</b></code></td>
    <td>matches any part of a name not containing the package separator or
        directory separator.</td></tr>
<tr><td valign="top"><code><b>**</b></code></td>
    <td>matches any part of a name, possibly containing any number of
        package separators or directory separators.</td></tr>
</table>

For example, "<code>foo,*bar</code>" matches the name <code>foo</code> and
all names ending with <code>bar</code>.
<p>

Furthermore, a name can be preceded by a negating exclamation mark '<b>!</b>'
to <i>exclude</i> the name from further attempts to match
with <i>subsequent</i> names. So, if a name matches an item in the filter, it
is accepted or rejected right away, depending on whether the item has a
negator. If the name doesn't match the item, it is tested against the next
item, and so on. It if doesn't match any items, it is accepted or rejected,
depending on the whether the last item has a negator or not.
<p>
For example, "<code>!foobar,*bar</code>" matches all names ending with
<code>bar</code>, except <code>foobar</code>.
<p>

<a name="keepoverview">&nbsp;</a>
<h2>Overview of <code>Keep</code> Options</h2>

The various <code>-keep</code> options for shrinking and obfuscation may seem
a bit confusing at first, but there's actually a pattern behind them. The
following table summarizes how they are related:
<p>

<table cellpadding="5">

<tr>
<th>Keep</th>
<td>From being removed or renamed</td>
<td>From being renamed</td>
</tr>

<tr>
<td>Classes and class members</td>
<td bgcolor="#E0E0E0"><a href="#keep"><code>-keep</code></a></td>
<td bgcolor="#E0E0E0"><a href="#keepnames"><code>-keepnames</code></a></td>
</tr>

<tr>
<td>Class members only</td>
<td bgcolor="#E0E0E0"><a href="#keepclassmembers"><code>-keepclassmembers</code></a></td>
<td bgcolor="#E0E0E0"><a href="#keepclassmembernames"><code>-keepclassmembernames</code></a></td>
</tr>

<tr>
<td>Classes and class members, if class members present</td>
<td bgcolor="#E0E0E0"><a href="#keepclasseswithmembers"><code>-keepclasseswithmembers</code></a></td>
<td bgcolor="#E0E0E0"><a href="#keepclasseswithmembernames"><code>-keepclasseswithmembernames</code></a></td>
</tr>

</table>
<p>

Each of these <code>-keep</code> options is of course followed by a
<a href="#classspecification">specification</a> of the classes and class
members (fields and methods) to which it should be applied.
<p>
If you're not sure which option you need, you should probably simply use
<code>-keep</code>. It will make sure the specified classes and class members
are not removed in the shrinking step, and not renamed in the obfuscation step.
<p>
<table>
<tr><td valign="top">
<img src="attention.gif" width="64" height="64"alt="attention">
</td><td>
Always remember:
<ul>
<li>Specifying a class without class members only preserves the class as an
    entry point &mdash; any class members may then still be removed, optimized,
    or obfuscated.</li>
<li>Specifying a class member only preserves the class member as an entry
    point &mdash; any associated code may still be optimized and adapted.</li>
</ul>
</td></tr>
</table>
<p>

<a name="keepoptionmodifiers">&nbsp;</a>
<h2>Keep Option Modifiers</h2>

<dl>
<dt><a name="allowshrinking"><code><b>allowshrinking</b></code></a></dt>

<dd>Specifies that the entry points specified in the <a href="#keep">-keep</a>
    option may be shrunk, even if they have to be preserved otherwise. That
    is, the entry points may be removed in the shrinking step, but if they are
    necessary after all, they may not be optimized or obfuscated.</dd>

<dt><a name="allowoptimization"><code><b>allowoptimization</b></code></a></dt>

<dd>Specifies that the entry points specified in the <a href="#keep">-keep</a>
    option may be optimized, even if they have to be preserved otherwise. That
    is, the entry points may be altered in the optimization step, but they may
    not be removed or obfuscated. This modifier is only useful for achieving
    unusual requirements.</dd>

<dt><a name="allowobfuscation"><code><b>allowobfuscation</b></code></a></dt>

<dd>Specifies that the entry points specified in the <a href="#keep">-keep</a>
    option may be obfuscated, even if they have to be preserved otherwise. That
    is, the entry points may be renamed in the obfuscation step, but they may
    not be removed or optimized. This modifier is only useful for achieving
    unusual requirements.</dd>

</dl>
<p>

<a name="classspecification">&nbsp;</a>
<h2>Class Specifications</h2>

A class specification is a template of classes and class members (fields and
methods). It is used in the various <code>-keep</code> options and in the
<code>-assumenosideeffects</code> option. The corresponding option is only
applied to classes and class members that match the template.
<p>
The template was designed to look very Java-like, with some extensions for
wildcards. To get a feel for the syntax, you should probably look at the <a
href="examples.html">examples</a>, but this is an attempt at a complete formal
definition:
<p>

<pre>
[<b>@</b><i>annotationtype</i>] [[<b>!</b>]<b>public</b>|<b>final</b>|<b>abstract</b>|<b>@</b> ...] [<b>!</b>]<b>interface</b>|<b>class</b>|<b>enum</b> <i>classname</i>
    [<b>extends</b>|<b>implements</b> [<b>@</b><i>annotationtype</i>] <i>classname</i>]
[<b>{</b>
    [<b>@</b><i>annotationtype</i>] [[<b>!</b>]<b>public</b>|<b>private</b>|<b>protected</b>|<b>static</b>|<b>volatile</b>|<b>transient</b> ...] <b>&lt;fields&gt;</b> |
                                                                      (<i>fieldtype fieldname</i>)<b>;</b>
    [<b>@</b><i>annotationtype</i>] [[<b>!</b>]<b>public</b>|<b>private</b>|<b>protected</b>|<b>static</b>|<b>synchronized</b>|<b>native</b>|<b>abstract</b>|<b>strictfp</b> ...] <b>&lt;methods&gt;</b> |
                                                                                           <b>&lt;init&gt;(</b><i>argumenttype,...</i><b>)</b> |
                                                                                           <i>classname</i><b>(</b><i>argumenttype,...</i><b>)</b> |
                                                                                           (<i>returntype methodname</i><b>(</b><i>argumenttype,...</i><b>)</b>)<b>;</b>
    [<b>@</b><i>annotationtype</i>] [[<b>!</b>]<b>public</b>|<b>private</b>|<b>protected</b>|<b>static</b> ... ] <b>*;</b>
    ...
<b>}</b>]
</pre>
<p>
Square brackets "[]" mean that their contents are optional. Ellipsis dots
"..." mean that any number of the preceding items may be specified. A vertical
bar "|" delimits two alternatives. Non-bold parentheses "()" just group parts
of the specification that belong together. The indentation tries to clarify
the intended meaning, but white-space is irrelevant in actual configuration
files.
<p>
<ul>

<li>The <code><b>class</b></code> keyword refers to any interface or class.
    The <code><b>interface</b></code> keyword restricts matches to interface
    classes. The <code><b>enum</b></code> keyword restricts matches to
    enumeration classes. Preceding the <code><b>interface</b></code> or
    <code><b>enum</b></code> keywords by a <code><b>!</b></code> restricts
    matches to classes that are not interfaces or enumerations, respectively.
    <p>

<li>Every <i>classname</i> must be fully qualified, e.g.
    <code>java.lang.String</code>. Class names may be specified as regular
    expressions containing the following wildcards:

<table cellspacing="10">

<tr><td valign="top"><code><b>?</b></code></td>

<td>matches any single character in a class name, but not the package
    separator. For example, "<code>mypackage.Test?</code>" matches
    "<code>mypackage.Test1</code>" and "<code>mypackage.Test2</code>", but not
    "<code>mypackage.Test12</code>".</td></tr>

<tr><td valign="top"><code><b>*</b></code></td>

<td>matches any part of a class name not containing the package separator. For
    example, "<code>mypackage.*Test*</code>" matches
    "<code>mypackage.Test</code>" and
    "<code>mypackage.YourTestApplication</code>", but not
    "<code>mypackage.mysubpackage.MyTest</code>". Or, more generally,
    "<code>mypackage.*</code>" matches all classes in
    "<code>mypackage</code>", but not in its subpackages.</td></tr>

<tr><td valign="top"><code><b>**</b></code></td>

<td>matches any part of a class name, possibly containing any number of
    package separators. For example, "<code>**.Test</code>" matches all
    <code>Test</code> classes in all packages except the root package. Or,
    "<code>mypackage.**</code>" matches all classes in
    "<code>mypackage</code>" and in its subpackages.</td></tr>

</table>

    For additional flexibility, class names can actually be comma-separated
    lists of class names, with optional <code><b>!</b></code> negators, just
    like file name filters. This notation doesn't look very Java-like, so it
    should be used with moderation.
    <p>
    For convenience and for backward compatibility, the class name
    <code><b>*</b></code> refers to any class, irrespective of its package.
    <p>

<li>The <code><b>extends</b></code> and <code><b>implements</b></code>
    specifications are typically used to restrict classes with wildcards. They
    are currently equivalent, specifying that only classes extending or
    implementing the given class qualify. Note that the given class itself is
    not included in this set. If required, it should be specified in a
    separate option.
    <p>

<li>The <code><b>@</b></code> specifications can be used to restrict classes
    and class members to the ones that are annotated with the specified
    annotation types. An <i>annotationtype</i> is specified just like a
    <i>classname</i>.
    <p>

<li>Fields and methods are specified much like in Java, except that method
    argument lists don't contain argument names (just like in other tools
    like <code>javadoc</code> and <code>javap</code>). The specifications can
    also contain the following catch-all wildcards:

<table cellspacing="10">

<tr><td valign="top"><code><b>&lt;init&gt;</b></code></td>
<td>matches any constructor.</td></tr>

<tr><td valign="top"><code><b>&lt;fields&gt;</b></code></td>
<td>matches any field.</td></tr>

<tr><td valign="top"><code><b>&lt;methods&gt;</b></code></td>
<td>matches any method.</td></tr>

<tr><td valign="top"><code><b>*</b></code></td>
<td>matches any field or method.</td></tr>

</table>

    Note that the above wildcards don't have return types. Only the
    <code><b>&lt;init&gt;</b></code> wildcard has an argument list.
    <p>

    Fields and methods may also be specified using regular expressions. Names
    can contain the following wildcards:

<table cellspacing="10">
<tr><td valign="top"><code><b>?</b></code></td>
    <td>matches any single character in a method name.</td></tr>
<tr><td valign="top"><code><b>*</b></code></td>
    <td>matches any part of a method name.</td></tr>
</table>

    Types in descriptors can contain the following wildcards:

<table cellspacing="10">
<tr><td valign="top"><code><b>%</b></code></td>
    <td>matches any primitive type ("<code>boolean</code>", "<code>int</code>",
        etc, but not "<code>void</code>").</td></tr>
<tr><td valign="top"><code><b>?</b></code></td>
    <td>matches any single character in a class name.</td></tr>
<tr><td valign="top"><code><b>*</b></code></td>
    <td>matches any part of a class name not containing the package                     separator.</td></tr>
<tr><td valign="top"><code><b>**</b></code></td>
    <td>matches any part of a class name, possibly containing any number of
        package separators.</td></tr>
<tr><td valign="top"><code><b>***</b></code></td>
    <td>matches any type (primitive or non-primitive, array or
        non-array).</td></tr>
<tr><td valign="top"><code><b>...</b></code></td>
    <td>matches any number of arguments of any type.</td></tr>

</table>

    Note that the <code>?</code>, <code>*</code>, and <code>**</code>
    wildcards will never match primitive types. Furthermore, only the
    <code>***</code> wildcards will match array types of any dimension. For
    example, "<code>** get*()</code>" matches "<code>java.lang.Object
    getObject()</code>", but not "<code>float getFloat()</code>", nor
    "<code>java.lang.Object[] getObjects()</code>".
    <p>

<li>Constructors can also be specified using their short class names (without
    package) or using their full class names. As in the Java language, the
    constructor specification has an argument list, but no return type.
    <p>

<li>The class access modifiers and class member access modifiers are typically
    used to restrict wildcarded classes and class members. They specify that
    the corresponding access flags have to be set for the member to match. A
    preceding <code><b>!</b></code> specifies that the corresponding access
    flag should be unset.
    <p>
    Combining multiple flags is allowed (e.g. <code>public static</code>). It
    means that both access flags have to be set (e.g. <code>public</code>
    <i>and</i> <code>static</code>), except when they are conflicting, in
    which case at least one of them has to be set (e.g. at least
    <code>public</code>
    <i>or</i> <code>protected</code>).

</ul>
<p>

<hr>
<address>
Copyright &copy; 2002-2009
<a href="http://www.graphics.cornell.edu/~eric/">Eric Lafortune</a>.
</address>
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