4. Running FindBugs™

FindBugs has two user interfaces: a graphical user interface (GUI) and a command line user interface. This chapter describes how to run each of these user interfaces.

$Warning$	Warning
	This chapter is in the process of being re-written. The rewrite is not complete yet.

1. Quick Start

If you are running FindBugs on a Windows system, double-click on the file %FINDBUGS_HOME% \lib\findbugs.jar to start the FindBugs GUI.

On a Unix, Linux, or Mac OS X system, run the $FINDBUGS_HOME /bin/findbugs script, or run the command

java -jar  $FINDBUGS_HOME /lib/findbugs.jar

to run the FindBugs GUI.

Refer to Chapter 5, Using the FindBugs GUI for information on how to use the GUI.

2. Executing FindBugs

This section describes how to invoke the FindBugs program. There are two ways to invoke FindBugs: directly, or using a wrapper script.

2.1. Direct invocation of FindBugs

The preferred method of running FindBugs is to directly execute $FINDBUGS_HOME /lib/findbugs.jar using the -jar command line switch of the JVM (java) executable. (Versions of FindBugs prior to 1.3.5 required a wrapper script to invoke FindBugs.)

The general syntax of invoking FindBugs directly is the following:

    java  [JVM arguments]  -jar  $FINDBUGS_HOME /lib/findbugs.jar  options...

2.1.1. Choosing the User Interface

The first command line option chooses the FindBugs user interface to execute. Possible values are:

-gui: runs the graphical user interface (GUI)
-textui: runs the command line user interface
-version: displays the FindBugs version number
-help: displays help information for the FindBugs command line user interface
-gui1: executes the original (obsolete) FindBugs graphical user interface

2.1.2. Java Virtual Machine (JVM) arguments

Several Java Virtual Machine arguments are useful when invoking FindBugs.

-Xmx NN m

Set the maximum Java heap size to NN megabytes. FindBugs generally requires a large amount of memory. For a very large project, using 1500 megabytes is not unusual.

-D name = value

Set a Java system property. For example, you might use the argument -Duser.language=ja to display GUI messages in Japanese.

2.2. Invocation of FindBugs using a wrapper script

Another way to run FindBugs is to use a wrapper script.

On Unix-like systems, use the following command to invoke the wrapper script:

$ $FINDBUGS_HOME /bin/findbugs  options...

On Windows systems, the command to invoke the wrapper script is

C:\My Directory>%FINDBUGS_HOME% \bin\findbugs.bat  options...

On both Unix-like and Windows systems, you can simply add the $FINDBUGS_HOME /bin directory to your PATH environment variable and then invoke FindBugs using the findbugs command.

2.2.1. Wrapper script command line options

The FindBugs wrapper scripts support the following command-line options. Note that these command line options are not handled by the FindBugs program per se; rather, they are handled by the wrapper script.

-jvmArgs args

Specifies arguments to pass to the JVM. For example, you might want to set a JVM property:

$ findbugs -textui -jvmArgs "-Duser.language=ja"  myApp.jar

-javahome directory

Specifies the directory containing the JRE (Java Runtime Environment) to use to execute FindBugs.

-maxHeap size

Specifies the maximum Java heap size in megabytes. The default is 256. More memory may be required to analyze very large programs or libraries.

-debug

Prints a trace of detectors run and classes analyzed to standard output. Useful for troubleshooting unexpected analysis failures.

-property name=value

This option sets a system property. FindBugs uses system properties to configure analysis options. See Chapter 9, Analysis Properties. You can use this option multiple times in order to set multiple properties. Note: In most versions of Windows, the name=value string must be in quotes.

3. Command-line Options

This section describes the command line options supported by FindBugs. These command line options may be used when invoking FindBugs directly, or when using a wrapper script.

3.1. Common command-line options

These options may be used with both the GUI and command-line interfaces.

-effort:min

This option disables analyses that increase precision but also increase memory consumption. You may want to try this option if you find that FindBugs runs out of memory, or takes an unusually long time to complete its analysis.

-effort:max

Enable analyses which increase precision and find more bugs, but which may require more memory and take more time to complete.

-project project

Specify a project to be analyzed. The project file you specify should be one that was created using the GUI interface. It will typically end in the extension .fb or .fbp.

3.2. GUI Options

These options are only accepted by the Graphical User Interface.

-look:plastic|gtk|native

Set Swing look and feel.

3.3. Text UI Options

These options are only accepted by the Text User Interface.

-sortByClass

Sort reported bug instances by class name.

-include filterFile.xml

Only report bug instances that match the filter specified by filterFile.xml . See Chapter 8, Filter Files.

-exclude filterFile.xml

Report all bug instances except those matching the filter specified by filterFile.xml . See Chapter 8, Filter Files.

-onlyAnalyze com.foobar.MyClass,com.foobar.mypkg.*

Restrict analysis to find bugs to given comma-separated list of classes and packages. Unlike filtering, this option avoids running analysis on classes and packages that are not explicitly matched: for large projects, this may greatly reduce the amount of time needed to run the analysis. (However, some detectors may produce inaccurate results if they aren't run on the entire application.) Classes should be specified using their full classnames (including package), and packages should be specified in the same way they would in a Java import statement to import all classes in the package (i.e., add .* to the full name of the package). Replace .* with .- to also analyze all subpackages.

-low

Report all bugs.

-medium

Report medium and high priority bugs. This is the default setting.

-high

Report only high priority bugs.

-relaxed

Relaxed reporting mode. For many detectors, this option suppresses the heuristics used to avoid reporting false positives.

-xml

Produce the bug reports as XML. The XML data produced may be viewed in the GUI at a later time. You may also specify this option as -xml:withMessages; when this variant of the option is used, the XML output will contain human-readable messages describing the warnings contained in the file. XML files generated this way are easy to transform into reports.

-html

Generate HTML output. By default, FindBugs will use the default.xsl XSLT stylesheet to generate the HTML: you can find this file in findbugs.jar, or in the FindBugs source or binary distributions. Variants of this option include -html:plain.xsl, -html:fancy.xsl and -html:fancy-hist.xsl. The plain.xsl stylesheet does not use Javascript or DOM, and may work better with older web browsers, or for printing. The fancy.xsl stylesheet uses DOM and Javascript for navigation and CSS for visual presentation. The fancy-hist.xsl an evolution of fancy.xsl stylesheet. It makes an extensive use of DOM and Javascript for dynamically filtering the lists of bugs.

If you want to specify your own XSLT stylesheet to perform the transformation to HTML, specify the option as -html: myStylesheet.xsl , where myStylesheet.xsl is the filename of the stylesheet you want to use.

-emacs

Produce the bug reports in Emacs format.

-xdocs

Produce the bug reports in xdoc XML format for use with Apache Maven.

-output filename

Produce the output in the specified file.

-outputFile filename

This argument is deprecated. Use -output instead.

-nested[:true|false]

This option enables or disables scanning of nested jar and zip files found in the list of files and directories to be analyzed. By default, scanning of nested jar/zip files is enabled. To disable it, add -nested:false to the command line arguments.

-auxclasspath classpath

Set the auxiliary classpath for analysis. This classpath should include all jar files and directories containing classes that are part of the program being analyzed but you do not want to have analyzed for bugs.

-auxclasspathFromInput

Read the auxiliary classpath for analysis from standard input, each line adds new entry to the auxiliary classpath for analysis.

-auxclasspathFromFile filepath

Read the auxiliary classpath for analysis from file, each line adds new entry to the auxiliary classpath for analysis.

-analyzeFromFile filepath

Read the files to analyze from file, each line adds new entry to the classpath for analysis.

-userPrefs edu.umd.cs.findbugs.core.prefs

Set the path of the user preferences file to use, which might override some of the options abobe. Specifying userPrefs as first argument would mean some later options will override them, as last argument would mean they will override some previous options). This rationale behind this option is to reuse FindBugs Eclipse project settings for command line execution.