You can find the ProGuard GUI jar in the lib directory of the ProGuard distribution. To run the ProGuard graphical user interface, just type:

proguardgui [-nosplash] [configuration_file]

Alternatively, the bin directory contains some short Linux and Windows scripts containing this command. The GUI will pop up in a window. With the -nosplash option, you can switch off the short opening animation. If you have specified a ProGuard configuration file, it will be loaded. The GUI works like a wizard. You can edit the configuration and execute ProGuard through a few tabs:

ProGuard
Input/Output
Shrinking
Obfuscation
Optimization
Information
Process

In addition, there is a tab to execute ReTrace interactively:

ReTrace

You can freely toggle between the tabs by means of the buttons on the left-hand side of the window, or by means of the Previous and Next buttons at the bottom of the tabs. Tool tips briefly explain the purpose of the numerous options and text fields, although a basic understanding of the shrinking/optimization/obfuscation/preverification process is assumed. Please refer to the Introduction of this manual.

The ProGuard tab {: #proguard}

The ProGuard tab presents a welcome message and one important button at the bottom:

Load configuration...

If you don't want to load an existing configuration, you can just continue creating a new configuration from scratch.

The Input/Output tab {: #inputoutput}

The Input/Output tab contains two lists, respectively to specify the program jars (or aars, wars, ears, zips, apks, or directories), and the library jars (or aars, wars, ears, zips, apks, or directories).

  • The list of program jars contains input entries and output entries. Input entries contain the class files and resource files to be processed. Output entries specify the destinations to which the processed results will be written. They are preceded by arrows, to distinguish them from input entries. The results of each consecutive list of input entries will be written to the subsequent consecutive list of output entries.
  • The library jars are not copied to the output jars; they contain class files that are used by class files in the program jars and that are necessary for correct processing. This list typically at least contains the targeted Java runtime jar.

Each of these lists can be edited by means of a couple of buttons on the right-hand side:

Add input...
Add output...
Add...
Edit...
Filter...
Remove
Move up
Move down
Move to libraries
Move to program

Filters allow to filter files based on their names. You can specify filters for class file names and resource file names, for jar file names, for aar file names, for war file names, for ear file names, for zip file names, and for apk file names. Multiple entries in the program list only make sense when combined with filters; each output file is written to the first entry with a matching filter.

Input entries that are currently not readable are colored red.

The order of the entries in each list may matter, as the first occurrence of any duplicate entries gets precedence, just as in conventional class paths.

Corresponding configuration options:

The Shrinking tab {: #shrinking}

The Shrinking tab presents a number of options that affect the shrinking step. The basic options are followed by a few lists of classes and class members (fields and methods) that must be protected from shrinking (and implicitly from obfuscation as well).

The fixed lists contain predefined entries that are typically useful for many applications. Each of these entries can be toggled by means of a check box. The text field following each entry allows to constrain the applicable classes by means of a comma-separated list of wildcarded, fully-qualified class names. The default is “*”, which means that all input classes of the corresponding type are considered.

For example, checking the Applications entry and filling in “myapplications.**” after it would mean: keep all classes that have main methods in the “myapplications” package and all of its subpackages.

The variable list at the bottom allows to define additional entries yourself. The list can be edited by means of a couple of buttons on the right-hand side:

Add...
Edit...
Remove
Move up
Move down

The interface windows allow to specify classes, fields, and methods. They contain text fields and check boxes to constrain these items. They have Ok and Cancel buttons to apply or to cancel the operation.

For example, your application may be creating some classes dynamically using Class.forName. You should then specify them here, so they are kept by their original names. Press the Add... button to open the class window. Fill out the fully-qualified class name in the Code text field, and press the Ok button. Repeat this for all required classes. Wildcards can be helpful to specify a large number of related classes in one go. If you want to specify all implementations of a certain interface, fill out the fully qualified interface name in the Extends/implements class instead.

For more advanced settings, it is advisable to become familiar with ProGuard‘s configuration options through the Usage section and the Examples section. We’ll suffice with a brief overview of the three dialogs provided by the GUI.

The keep class dialog appears when adding or editing new special keep entries. It has text fields and selections for specifying and constraining classes and class members to keep. The Advanced options / Basic options button at the bottom of the dialog allows to toggle showing the advanced options.

  • The Comments text field allows to add optional comments to this entry. The comments will identify the entry in the list and they will appear as comments in the configuration file.
  • The Keep selection allows to specify whether you want to protect the specified classes and their specified class members, or just the specified class members from the specified classes, or the specified classes and the specified class members, if the class members are present. Note that class members will only be protected if they are explicitly specified, even if only by means of a wildcard.
  • The Allow selection allows to specify whether you want to allow the the specified classes and their specified class members to be shrunk, optimized and/or obfuscated.
  • The Access selections allows to specify constraints on the class or classes, based on their access modifiers.
  • The Annotation text field takes the fully-qualified name of an annotation that is required for matching classes. The annotation name can contain wildcards. This is an advanced option for defining keep annotations.
  • The Class text field takes the fully-qualified name of the class or classes. The class name can contain wildcards.
  • The Annotation text field takes the fully-qualified name of an annotation that is required for the class or interface that the above class must extend. The annotation name can contain wildcards. This is an advanced option for defining keep annotations.
  • The Extends/implements class text field takes the fully-qualified name of the class or interface that the above classes must extend.
  • The Class members list allows to specify a list of fields and methods to keep. It can be edited by means of a list of buttons on the right-hand side.

The keep field dialog appears when adding or editing fields within the above dialog. It has text fields and selections for specifying and constraining fields to keep. Again, the Advanced options / Basic options button at the bottom of the dialog allows to toggle showing the advanced options.

  • The Access selections allows to specify constraints on the field or fields, based on their access modifiers.
  • The Annotation text field takes the fully-qualified name of an annotation that is required for matching fields. The annotation name can contain wildcards. This is an advanced option for defining keep annotations.
  • The Return type text field takes the fully-qualified type of the field or fields. The type can contain wildcards.
  • The Name text field takes the name of the field or fields. The field name can contain wildcards.

Similarly, the keep method dialog appears when adding or editing methods within the keep class dialog. It has text fields and selections for specifying and constraining methods to keep. Again, the Advanced options / Basic options button at the bottom of the dialog allows to toggle showing the advanced options.

  • The Access selections allows to specify constraints on the method or methods, based on their access modifiers.
  • The Annotation text field takes the fully-qualified name of an annotation that is required for matching methods. The annotation name can contain wildcards. This is an advanced option for defining keep annotations.
  • The Return type text field takes the fully-qualified type of the method or methods. The type can contain wildcards.
  • The Name text field takes the name of the method or methods. The method name can contain wildcards.
  • The Arguments text field takes the comma-separated list of fully-qualified method arguments. Each of these arguments can contain wildcards.

Corresponding configuration options:

The Obfuscation tab {: #obfuscation}

The Obfuscation tab presents a number of options that affect the obfuscation step. The basic options are followed by a few lists of classes and class members (fields and methods) that must be protected from obfuscation (but not necessarily from shrinking).

The lists are manipulated in the same way as in the Shrinking tab.

Corresponding configuration options:

The Optimization tab {: #optimization}

The Optimization tab presents a number of options that affect the optimization step. The basic options are followed by a few lists of class method calls that can be removed if ProGuard can determine that their results are not being used.

The lists are manipulated in much the same way as in the Shrinking tab.

Corresponding configuration options:

The Information tab {: #information}

The Information tab presents a number of options for preverification and targeting, and for the information that ProGuard returns when processing your code. The bottom list allows you to query ProGuard about why given classes and class members are being kept in the shrinking step.

Corresponding configuration options:

The Process tab {: #process}

The Process tab has an output console for displaying the configuration and the messages while processing. There are three important buttons at the bottom:

View configuration
Save configuration...
Process!

The ReTrace tab {: #retrace}

The ReTrace tab has a panel with a few settings, an input text area for the obfuscated stack trace, and an output console to view the de-obfuscated stack trace:

  • The Verbose check box in the settings panel allows to toggle between normal mode and verbose mode.
  • The Mapping file text field takes the name of the required mapping file that ProGuard wrote while processing the original code. The file name can be entered manually or by means of the Browse... button that opens a file chooser.
  • The Obfuscated stack trace text area allows to enter the stack trace, typically by copying and pasting it from elsewhere. Alternatively, it can be loaded from a file by means of the load button below.

There are two buttons at the bottom:

Load stack trace...
ReTrace!