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<title>ProGuard Troubleshooting</title>
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<h2>Troubleshooting</h2>
While preparing a configuration for processing your code, you may bump into a
few problems. The following sections discuss some common issues and solutions:
<h3><a href="#processing">Problems while processing</a></h3>
<ul>
<li><a href="#dynamicalclass">Note: can't find dynamically referenced class</a></li>
<li><a href="#dynamicalclasscast">Note: ... calls '(...)Class.forName(variable).newInstance()'</a></li>
<li><a href="#dynamicalclassmember">Note: ... accesses a field/method '...' dynamically</a></li>
<li><a href="#descriptorclass">Note: the configuration keeps the entry point '...', but not the descriptor class '...'</a></li>
<li><a href="#duplicateclass">Note: duplicate definition of program/library class</a></li>
<li><a href="#duplicatezipentry">Warning: can't write resource ... Duplicate zip entry</a></li>
<li><a href="#unresolvedclass">Warning: can't find superclass or interface</a></li>
<li><a href="#unresolvedclass">Warning: can't find referenced class</a></li>
<li><a href="#unresolvedclassmember">Warning: can't find referenced field/method</a></li>
<li><a href="#unresolvedenclosingmethod">Warning: can't find enclosing class/method</a></li>
<li><a href="#dependency">Warning: library class ... depends on program class ...</a></li>
<li><a href="#unexpectedclass">Warning: class file ... unexpectedly contains class ...</a></li>
<li><a href="#mappingconflict1">Warning: ... is not being kept as ..., but remapped to ...</a></li>
<li><a href="#mappingconflict2">Warning: field/method ... can't be mapped to ...</a></li>
<li><a href="#keep">Error: You have to specify '-keep' options</a></li>
<li><a href="#filename">Error: Expecting class path separator ';' before 'Files\Java\...' (in Windows)</a></li>
<li><a href="#macosx">Error: Can't read [.../lib/rt.jar] (No such file or directory) (in MacOS X)</a></li>
<li><a href="#outofmemoryerror">OutOfMemoryError</a></li>
<li><a href="#stackoverflowerror">StackOverflowError</a></li>
<li><a href="#unexpectederror">Unexpected error</a></li>
<li><a href="#otherwise">Otherwise...</a></li>
</ul>
<h3><a href="#afterprocessing">Unexpected observations after processing</a></h3>
<ul>
<li><a href="#disappearingclasses">Disappearing classes</a></li>
<li><a href="#notkept">Classes or class members not being kept</a></li>
<li><a href="#notobfuscated">Variable names not being obfuscated</a></li>
</ul>
<h3><a href="#preverifying">Problems while preverifying for Java Micro Edition</a></h3>
<ul>
<li><a href="#invalidclassexception1">InvalidClassException, class loading error, or verification error</a></li>
</ul>
<h3><a href="#runtime">Problems at run-time</a></h3>
<ul>
<li><a href="#stacktraces">Stack traces without class names or line numbers</a></li>
<li><a href="#noclassdeffounderror">NoClassDefFoundError</a></li>
<li><a href="#classnotfoundexception">ClassNotFoundException</a></li>
<li><a href="#nosuchmethodexception">NoSuchMethodException</a></li>
<li><a href="#missingresourceexception">MissingResourceException or NullPointerException</a></li>
<li><a href="#invalidjarfile">Invalid or corrupt jarfile</a></li>
<li><a href="#invalidclassexception2">InvalidClassException, class loading error, or verification error (in Java Micro Edition)</a></li>
<li><a href="#nosuchfieldormethod">Error: No Such Field or Method, Error verifying method (in a Java Micro Edition emulator)</a></li>
<li><a href="#failingmidlets">Failing midlets (on a Java Micro Edition device)</a></li>
<li><a href="#disappearingloops">Disappearing loops</a></li>
<li><a href="#securityexception">SecurityException: SHA1 digest error</a></li>
<li><a href="#classcastexception">ClassCastException: class not an enum</a></li><li><a href="#classcastexception">IllegalArgumentException: class not an enum type</a></li>
<li><a href="#arraystoreexception">ArrayStoreException: sun.reflect.annotation.EnumConstantNotPresentExceptionProxy</a></li>
<li><a href="#compilererror">CompilerError: duplicate addition</a></li>
<li><a href="#classformaterror">ClassFormatError: repetitive field name/signature</a></li>
<li><a href="#nosuchmethoderror">NoSuchMethodError or AbstractMethodError</a></li>
<li><a href="#verifyerror">VerifyError</a></li>
</ul>
<a name="processing">&nbsp;</a>
<h2>Problems while processing</h2>
ProGuard may print out some notes and non-fatal warnings:
<dl>
<dt><a name="dynamicalclass"><b>Note: can't find dynamically referenced class</b></a></dt>
<dd>ProGuard can't find a class or interface that your code is accessing by
means of introspection. You should check if you want to add the jar that
contains this class.</dd>
<dt><a name="dynamicalclasscast"><b>Note: ... calls '(...)Class.forName(variable).newInstance()'</b></a></dt>
<dd>ProGuard lists all class casts of dynamically created class instances,
like "<code>(MyClass)Class.forName(variable).newInstance()</code>".
Depending on your application, you may need to keep the mentioned classes
with an option like "<code>-keep class MyClass</code>", or their
implementations with an option like "<code>-keep class * implements
MyClass</code>". You can switch off these notes by specifying the
<a href="usage.html#dontnote"><code>-dontnote</code></a> option.</dd>
<dt><a name="dynamicalclassmember"><b>Note: ... accesses a field/method '...' dynamically</b></a></dt>
<dd>ProGuard lists a number of constructs like
"<code>.getField("myField")</code>". Depending on your application, you
may need to figure out where the mentioned class members are defined and
keep them with an option like "<code>-keep class MyClass { MyFieldType
myField; }</code>". Otherwise, ProGuard might remove or obfuscate the
class members, since it can't know which ones they are exactly. It does
list possible candidates, for your information. You can switch off these
notes by specifying the <a
href="usage.html#dontnote"><code>-dontnote</code></a> option.</dd>
<dt><a name="descriptorclass"><b>Note: the configuration keeps the entry point '...', but not the descriptor class '...'</b></a></dt>
<dd>Your configuration contains a <code>-keep</code> option to preserve the
given method (or field), but no <code>-keep</code> option for the given
class that is an argument type or return type in the method's descriptor.
You may then want to keep the class too. Otherwise, ProGuard will
obfuscate its name, thus changing the method's signature. The method might
then become unfindable as an entry point, e.g. if it is part of a public
API. You can switch off these notes by specifying the <a
href="usage.html#dontnote"><code>-dontnote</code></a> option.</dd>
<dt><a name="duplicateclass"><b>Note: duplicate definition of program/library class</b></a></dt>
<dd>Your program jars or library jars contain multiple definitions of the
listed classes. ProGuard continues processing as usual, only considering
the first definitions. The warning may be an indication of some problem
though, so it's advisable to remove the duplicates. A convenient way to do
so is by specifying filters on the input jars or library jars. You can
switch off these notes by specifying the <a
href="usage.html#dontnote"><code>-dontnote</code></a> option.</dd>
<dt><a name="duplicatezipentry"><b>Warning: can't write resource ... Duplicate zip entry</b></a></dt>
<dd>Your input jars contain multiple resource files with the same name.
ProGuard continues copying the resource files as usual, skipping any files
with previously used names. Once more, the warning may be an indication of
some problem though, so it's advisable to remove the duplicates. A
convenient way to do so is by specifying filters on the input jars. There
is no option to switch off these warnings.</dd>
</dl>
<p>
ProGuard may terminate when it encounters parsing errors or I/O errors, or
some more serious warnings:
<dl>
<dt><a name="unresolvedclass"><b>Warning: can't find superclass or interface</b><br/><b>Warning: can't find referenced class</b></a></dt>
<dd>If there are unresolved references to classes or interfaces, you most
likely forgot to specify an essential library. For proper processing, all
libraries that are referenced by your code must be specified, including
the Java run-time library. For specifying libraries, use
the <a href="usage.html#libraryjars"><code>-libraryjars</code></a> option.
<p>
If the class that is reported as missing is a non-public library class,
you should specify the <a
href="usage.html#dontskipnonpubliclibraryclasses"><code>-dontskipnonpubliclibraryclasses</code></a>
option. Common examples are the classes
<code>javax.swing.TransferHandler$HasGetTransferHandler</code> and
<code>java.util.zip.ZipConstants</code>, which are used as interfaces in
some public classes, even though they are only package visible. This
option is not set by default for reasons of efficiency. Setting it increases
the processing time a bit, but it won't hurt the output in any way.
<p>
If you're missing a library and you're absolutely sure it isn't used
anyway, you can try your luck with the <a
href="usage.html#ignorewarnings"><code>-ignorewarnings</code></a> option,
or even the <a href="usage.html#dontwarn"><code>-dontwarn</code></a>
option. Only use these options if you really know what you're doing
though.</dd>
<dt><a name="unresolvedclassmember"><b>Warning: can't find referenced field/method</b></a></dt>
<dd>If there are unresolved references to class members in input classes, your
class files are most likely inconsistent. Possibly, some class file didn't
get recompiled properly, or some class file was left behind after its
source file was removed. Try removing all class files, recompiling them,
zipping them up, and running ProGuard again.
<p>
If the class member that is reported as missing is actually implemented in
a non-public library class, you should specify the
<a href="usage.html#dontskipnonpubliclibraryclasses"><code>-dontskipnonpubliclibraryclasses</code></a> option. A common example is
the method <code>setLength(int)</code> in the public class
<code>java.lang.StringBuilder</code>. This method is actually defined in
the package visible superclass
<code>java.lang.AbstractStringBuilder</code>, which ProGuard ignores by
default.
<p>
If your program classes reside in the same packages as library classes,
and refer to their package visible class members, then you should specify
the <a
href="usage.html#dontskipnonpubliclibraryclassmembers"><code>-dontskipnonpubliclibraryclassmembers</code></a>
option.</dd>
<dt><a name="unresolvedenclosingmethod"><b>Warning: can't find enclosing class/method</b></a></dt>
<dd>If there are unresolved references to classes that are defined inside
methods in your input, once more, your class files are most likely
inconsistent. Possibly, some class file didn't get recompiled properly, or
some class file was left behind after its source file was removed. Try
removing all class files, recompiling them, zipping them up, and running
ProGuard again.</dd>
<dt><a name="dependency"><b>Warning: library class ... depends on program class ...</b></a></dt>
<dd>If any of your library classes depend on your program classes, by
extending, implementing or just referencing them, your processed code will
generally be unusable. Program classes can depend on library classes, but
not the other way around. Program classes are processed, while library
classes always remain unchanged. It is therefore impossible to adapt
references from library classes to program classes, for instance if the
program classes are renamed. You should define a clean separation between
program code and library code, and try again.</dd>
<dt><a name="unexpectedclass"><b>Warning: class file ... unexpectedly contains class ...</b></a></dt>
<dd>The given class file contains a definition for the given class, but the
directory name of the file doesn't correspond to the package name of the
class. ProGuard will accept the class definition, but the current
implementation will not write out the processed version. Please make sure
your input classes are packaged correctly. Notably, class files that are
in the <code>WEB-INF/classes</code> directory in a war should be packaged
in a jar and put in the <code>WEB-INF/lib</code> directory. If you don't
mind these classes not being written to the output, you can specify the <a
href="usage.html#ignorewarnings"><code>-ignorewarnings</code></a> option,
or even the <a href="usage.html#dontwarn"><code>-dontwarn</code></a>
option.</dd>
<dt><a name="mappingconflict1"><b>Warning: ... is not being kept as ..., but remapped to ...</b></a></dt>
<dd>There is a conflict between a <code>-keep</code> option in the
configuration, and the mapping file, in the obfuscation step. The given
class name or class member name can't be kept by its original name, as
specified in the configuration, but it has to be mapped to the other given
name, as specified in the mapping file. You should adapt your
configuration or your mapping file to remove the conflict. Alternatively,
if you're sure the renaming won't hurt, you can specify the <a
href="usage.html#ignorewarnings"><code>-ignorewarnings</code></a> option,
or even the <a href="usage.html#dontwarn"><code>-dontwarn</code></a>
option.</dd>
<dt><a name="mappingconflict2"><b>Warning: field/method ... can't be mapped to ...</b></a></dt>
<dd>There is a conflict between some new program code and the mapping file, in
the obfuscation step. The given class member can't be mapped to the given
name, because it would conflict with another class member that is already
being mapped to the same name. This can happen if you are performing
incremental obfuscation, applying an obfuscation mapping file from an
initial obfuscation step. For instance, some new class may have been added
that extends two existing classes, introducing a conflict in the name
space of its class members. If you're sure the class member receiving
another name than the one specified won't hurt, you can specify the <a
href="usage.html#ignorewarnings"><code>-ignorewarnings</code></a> option,
or even the <a href="usage.html#dontwarn"><code>-dontwarn</code></a>
option. Note that you should always use the <a
href="usage.html#useuniqueclassmembernames"><code>-useuniqueclassmembernames</code></a>
option in the initial obfuscation step, in order to reduce the risk of
conflicts.</dd>
<dt><a name="keep"><b>Error: You have to specify '-keep' options</b></a></dt>
<dd>You either forgot to specify <a
href="usage.html#keep"><code>-keep</code></a> options, or you mistyped the
class names. ProGuard has to know exactly what you want to keep: an
application, an applet, a servlet, a midlet,..., or any combination of
these. Without the proper seed specifications, ProGuard would shrink,
optimize, or obfuscate all class files away.</dd>
<dt><a name="filename"><b>Error: Expecting class path separator ';' before 'Files\Java\</b>...<b>'</b> (in Windows)</a></dt>
<dd>If the path of your run-time jar contains spaces, like in "Program Files",
you have to enclose it with single or double quotes, as explained in the
section on <a href="usage.html#filename">file names</a>. This is actually
true for all file names containing special characters, on all
platforms.</dd>
<dt><a name="macosx"><b>Error: Can't read [</b>...<b>/lib/rt.jar] (No such file or directory)</b> (in MacOS X)</a></dt>
<dd>In MacOS X, the run-time classes may be in a different place than on most
other platforms. You'll then have to adapt your configuration, replacing
the path <code>&lt;java.home&gt;/lib/rt.jar</code> by
<code>&lt;java.home&gt;/../Classes/classes.jar</code>.</dd>
</dl>
<p>
Should ProGuard crash while processing your application:
<dl>
<dt><a name="outofmemoryerror"><b>OutOfMemoryError</b></a></dt>
<dd>You can try increasing the heap size of the Java virtual machine (with the
usual <code>-Xms</code> and <code>-Xmx</code> options). You can also
reduce the amount of memory that ProGuard needs by removing unnecessary
library jars from your configuration, or by filtering out unused library
packages and classes. Remember that only classes or interfaces that are
extended or implemented by classes in your input jars are required.</dd>
<dt><a name="stackoverflowerror"><b>StackOverflowError</b></a></dt>
<dd>This error might occur when processing a large code base on Windows
(surprisingly, not so easily on Linux). In theory, increasing the stack
size of the Java virtual machine (with the usual <code>-Xss</code> option)
should help too. In practice however, the <code>-Xss</code> setting
doesn't have any effect on the main thread, due to <a
href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4362291">Sun Bug
#4362291</a>. As a result, this solution will only work when running
ProGuard in a different thread, e.g. from its GUI.</dd>
<dt><a name="unexpectederror"><b>Unexpected error</b></a></dt>
<dd>ProGuard has encountered an unexpected condition, typically in the
optimization step. It may or may not recover. You should be able to avoid
it using the <a
href="usage.html#dontoptimize"><code>-dontoptimize</code></a> option. In
any case, please report the problem, preferably with the simplest example
that causes ProGuard to crash.</dd>
<dt><a name="otherwise"><b>Otherwise...</b></a></dt>
<dd>Maybe your class files are corrupt. See if recompiling them and trying
again helps. If not, please report the problem, preferably with the
simplest example that causes ProGuard to crash.</dd>
</dl>
<p>
<a name="afterprocessing">&nbsp;</a>
<h2>Unexpected observations after processing</h2>
If ProGuard seems to run fine, but your processed code doesn't look right,
there might be a couple of reasons:
<dl>
<dt><a name="disappearingclasses"><b>Disappearing classes</b></a></dt>
<dd>If you are working on Windows and it looks like some classes have
disappeared from your output, you should make sure you're not writing your
output class files to a directory (or unpacking the output jar). On
platforms with case-insensitive file systems, such as Windows, unpacking
tools often let class files with similar lower-case and upper-case names
overwrite each other. If you really can't switch to a different operating
system, you could consider using ProGuard's <a
href="usage.html#dontusemixedcaseclassnames"><code>-dontusemixedcaseclassnames</code></a>
option.
<p>
Also, you should make sure your class files are in directories that
correspond to their package names. ProGuard will read misplaced class
files, but it will currently not write their processed versions. Notably,
class files that are in the <code>WEB-INF/classes</code> directory in a
war should be packaged in a jar and put in the <code>WEB-INF/lib</code>
directory.</dd>
<dt><a name="notkept"><b>Classes or class members not being kept</b></a></dt>
<dd>If ProGuard is not keeping the right classes or class members, make sure
you are using fully qualified class names. If the package name of some
class is missing, ProGuard won't match the elements that you might be
expecting. It may help to double-check for typos too. You can use the <a
href="usage.html#printseeds"><code>-printseeds</code></a> option to see
which elements are being kept exactly.
<p>
If you are using marker interfaces to keep other classes, the marker
interfaces themselves are probably being removed in the shrinking step.
You should therefore always explicitly keep any marker interfaces.</dd>
<dt><a name="notobfuscated"><b>Variable names not being obfuscated</b></a></dt>
<dd>If the names of the local variables and parameters in your obfuscated code
don't look obfuscated, because they suspiciously resemble the names of
their types, it's probably because the decompiler that you are using is
coming up with those names. ProGuard's obfuscation step does remove the
original names entirely, unless you explicitly keep the
<code>LocalVariableTable</code> or <code>LocalVariableTypeTable</code>
attributes.</dd>
</dl>
<a name="preverifying">&nbsp;</a>
<h2>Problems while preverifying for Java Micro Edition</h2>
If ProGuard seems to run fine, but the external preverifier subsequently
produces errors, it's usually for a single reason:
<dl>
<dt><a name="invalidclassexception1"><b>InvalidClassException</b>, <b>class loading error</b>, or <b>verification error</b></a></dt>
<dd>If you get any such message from the preverifier, you are probably working
on a platform with a case-insensitive file system, such as Windows. The
<code>preverify</code> tool always unpacks the jars, so class files with
similar lower-case and upper-case names overwrite each other. You can use
ProGuard's <a
href="usage.html#dontusemixedcaseclassnames"><code>-dontusemixedcaseclassnames</code></a>
option to work around this problem.
<p>
If the above doesn't help, there is probably a bug in the optimization
step of ProGuard. Make sure you are using the latest version. You should
be able to work around the problem by using the <a
href="usage.html#dontoptimize"><code>-dontoptimize</code></a> option. You
can check the bug database to see if it is a known problem (often with a
fix). Otherwise, please report it, preferably with the simplest example on
which you can find ProGuard to fail.</dd>
</dl>
Note that it is no longer necessary to use an external preverifier. With the
<a href="usage.html#microedition"><code>-microedition</code></a> option,
ProGuard will preverify the class files for Java Micro Edition.
<p>
<a name="runtime">&nbsp;</a>
<h2>Problems at run-time</h2>
If ProGuard runs fine, but your processed application doesn't work, there
might be several reasons:
<dl>
<dt><a name="stacktraces"><b>Stack traces without class names or line numbers</b></a></dt>
<dd>If your stack traces don't contain any class names or lines numbers,
even though you are keeping the proper attributes, make sure this debugging
information is present in your compiled code to start with. Notably the Ant
javac task has debugging information switched off by default.</dd>
<dt><a name="noclassdeffounderror"><b>NoClassDefFoundError</b></a></dt>
<dd>Your class path is probably incorrect. It should at least contain all
library jars and, of course, your processed program jar.</dd>
<dt><a name="classnotfoundexception"><b>ClassNotFoundException</b></a></dt>
<dd>Your code is probably calling <code>Class.forName</code>, trying to create
the missing class dynamically. ProGuard can only detect constant name
arguments, like <code>Class.forName("mypackage.MyClass")</code>. For
variable name arguments like <code>Class.forName(someClass)</code>, you
have to keep all possible classes using the appropriate <a
href="usage.html#keep"><code>-keep</code></a> option, e.g. "<code>-keep
class mypackage.MyClass</code>" or "<code>-keep class * implements
mypackage.MyInterface</code>".</dd>
<dt><a name="nosuchmethodexception"><b>NoSuchMethodException</b></a></dt>
<dd>Your code is probably calling something like
<code>myClass.getMethod</code>, trying to find some method dynamically.
Since ProGuard isn't detecting this (yet), you have to keep the missing
method in using the appropriate <a
href="usage.html#keep"><code>-keep</code></a> option, e.g. "<code>-keep
class mypackage.MyClass { void myMethod(); }</code>".</dd>
<dt><a name="missingresourceexception"><b>MissingResourceException</b> or <b>NullPointerException</b></a></dt>
<dd>Your processed code may be unable to find some resource files. ProGuard
simply copies resource files over from the input jars to the output jars.
Their names and contents remain unchanged, unless you specify the options
<a
href="usage.html#adaptresourcefilenames"><code>-adaptresourcefilenames</code></a>
and/or <a
href="usage.html#adaptresourcefilecontents"><code>-adaptresourcefilecontents</code></a>.
<p>
Furthermore, directory entries in jar files aren't copied, unless you
specify the option <a
href="usage.html#keepdirectories"><code>-keepdirectories</code></a>.</dd>
<dt><a name="invalidjarfile"><b>Invalid or corrupt jarfile</b></a></dt>
<dd>You are probably starting your application with the java option
<code>-jar</code> instead of the option <code>-classpath</code>. The java
virtual machine returns with this error message if your jar doesn't
contain a manifest file (<code>META-INF/MANIFEST.MF</code>), if the
manifest file doesn't specify a main class (<code>Main-Class:</code> ...),
or if the jar doesn't contain this main class. You should then make sure
that the input jar contains a valid manifest file to start with, that this
manifest file is the one that is copied (the first manifest file that is
encountered), and that the main class is kept in your configuration,</dd>
<dt><a name="invalidclassexception2"><b>InvalidClassException</b>, <b>class loading error</b>, or <b>verification error</b> (in Java Micro Edition)</a></dt>
<dd>If you get such an error in Java Micro Edition, you may have forgotten to
specify the <a
href="usage.html#microedition"><code>-microedition</code></a> option, so
the processed class files are preverified properly.</dd>
<dt><a name="nosuchfieldormethod"><b>Error: No Such Field or Method</b>, <b>Error verifying method</b> (in a Java Micro Edition emulator)</a></dt>
<dd>If you get such a message in a Motorola or Sony Ericsson phone emulator,
it's because these emulators don't like packageless classes and/or
overloaded fields and methods. You can work around it by not using the
options <code><a href="usage.html#repackageclasses">-repackageclasses</a>
''</code> and <a
href="usage.html#overloadaggressively"><code>-overloadaggressively</code></a>.
If you're using the JME WTK plugin, you can adapt the configuration
<code>proguard/wtk/default.pro</code> that's inside the
<code>proguard.jar</code>.</dd>
<dt><a name="failingmidlets"><b>Failing midlets</b> (on a Java Micro Edition device)</a></dt>
<dd>If your midlet runs in an emulator and on some devices, but not on some
other devices, this is probably due to a bug in the latter devices. For
some older Motorola and Nokia phones, you might try specifying the <a
href="usage.html#useuniqueclassmembernames"><code>-useuniqueclassmembernames</code></a>
option. It avoids overloading class member names, which triggers a bug in
their java virtual machine.
<p>
You might also try using the <a
href="usage.html#dontusemixedcaseclassnames"><code>-dontusemixedcaseclassnames</code></a>
option. Even if the midlet has been properly processed and then
preverified on a case-sensitive file system, the device itself might not
like the mixed-case class names. Notably, the Nokia N-Gage emulator works
fine, but the actual device seems to exhibit this problem.</dd>
<dt><a name="disappearingloops"><b>Disappearing loops</b></a></dt>
<dd>If your code contains empty busy-waiting loops, ProGuard's optimization
step may remove them. More specifically, this happens if a loop
continuously checks the value of a non-volatile field that is changed in a
different thread. The specifications of the Java Virtual Machine require
that you always mark fields that are accessed across different threads
without further synchronization as <code>volatile</code>. If this is not
possible for some reason, you'll have to switch off optimization using the
<a href="usage.html#dontoptimize"><code>-dontoptimize</code></a>
option.</dd>
<dt><a name="securityexception"><b>SecurityException: SHA1 digest error</b></a></dt>
<dd>You may have forgotten to sign your program jar <i>after</i> having
processed it with ProGuard.</dd>
<dt><a name="classcastexception"><b>ClassCastException: class not an enum</b>, or <br><b>IllegalArgumentException: class not an enum type</b></a></dt>
<dd>You should make sure you're preserving the special methods of enumeration
types, which the run-time environment calls by introspection. The required
options are shown in the <a
href="examples.html#enumerations">examples</a>.</dd>
<dt><a name="arraystoreexception"><b>ArrayStoreException: sun.reflect.annotation.EnumConstantNotPresentExceptionProxy</b></a></dt>
<dd>You are probably processing annotations involving enumerations. Again, you
should make sure you're preserving the special methods of the enumeration
type, as shown in the examples.</dd>
<dt><a name="compilererror"><b>CompilerError: duplicate addition</b></a></dt>
<dd>You are probably compiling or running some code that has been obfuscated
with the <a
href="usage.html#overloadaggressively"><code>-overloadaggressively</code></a>
option. This option triggers a bug in
<code>sun.tools.java.MethodSet.add</code> in Sun's JDK 1.2.2, which is
used for (dynamic) compilation. You should then avoid this option.</dd>
<dt><a name="classformaterror"><b>ClassFormatError: repetitive field name/signature</b></a></dt>
<dd>You are probably processing some code that has been obfuscated before with
the <a
href="usage.html#overloadaggressively"><code>-overloadaggressively</code></a>
option. You should then use the same option again in the second processing
round.</dd>
<dt><a name="nosuchmethoderror"><b>NoSuchMethodError</b> or <b>AbstractMethodError</b></a></dt>
<dd>You should make sure you're not writing your output class files to a
directory on a platform with a case-insensitive file system, such as
Windows. Please refer to the section about <a
href="#disappearingclasses">disappearing classes</a> for details.
<p>
Furthermore, you should check whether you have specified your program jars
and library jars properly. Program classes can refer to library classes,
but not the other way around.
<p>
If all of this seems ok, perhaps there's a bug in ProGuard (gasp!). If so,
please report it, preferably with the simplest example on which you can
find ProGuard to fail.</dd>
<dt><a name="verifyerror"><b>VerifyError</b></a></dt>
<dd>Verification errors when executing a program are almost certainly the
result of a bug in the optimization step of ProGuard. Make sure you are
using the latest version. You should be able to work around the problem by
using the <a href="usage.html#dontoptimize"><code>-dontoptimize</code></a>
option. You can check the bug database to see if it is a known problem
(often with a fix). Otherwise, please report it, preferably with the
simplest example on which ProGuard fails.</dd>
</dl>
<hr>
<address>
Copyright &copy; 2002-2009
<a href="http://www.graphics.cornell.edu/~eric/">Eric Lafortune</a>.
</address>
</body>
</html>