Ant has two related features to allow the build process to be monitored: listeners and loggers.
Listeners A listener is alerted of the following events:
build started build finished target started target finished task started task finished message logged Loggers Loggers extend the capabilities of listeners and add the following features:
Receives a handle to the standard output and error print streams and therefore can log information to the console or the -logfile specified file. Logging level (-quiet, -verbose, -debug) aware Emacs-mode aware Built-in Listeners/Loggers Classname Description Type org.apache.tools.ant.DefaultLogger The logger used implicitly unless overridden with the -logger command-line switch. BuildLogger org.apache.tools.ant.NoBannerLogger This logger omits output of empty target output. BuildLogger org.apache.tools.ant.listener.MailLogger Extends DefaultLogger such that output is still generated the same, and when the build is finished an e-mail can be sent. BuildLogger org.apache.tools.ant.listener.AnsiColorLogger Colorifies the build output. BuildLogger org.apache.tools.ant.listener.Log4jListener Passes events to Log4j for highly customizable logging. BuildListener org.apache.tools.ant.XmlLogger Writes the build information to an XML file. BuildLogger
DefaultLogger Simply run Ant normally, or:
ant -logger org.apache.tools.ant.DefaultLogger
NoBannerLogger Removes output of empty target output.
ant -logger org.apache.tools.ant.NoBannerLogger
MailLogger The MailLogger captures all output logged through DefaultLogger (standard Ant output) and will send success and failure messages to unique e-mail lists, with control for turning off success or failure messages individually.
Properties controlling the operation of MailLogger:
Property Description Required MailLogger.mailhost Mail server to use No, default "localhost" MailLogger.from Mail "from" address Yes, if mail needs to be sent MailLogger.failure.notify Send build failure e-mails? No, default "true" MailLogger.success.notify Send build success e-mails? No, default "true" MailLogger.failure.to Address(es) to send failure messages to, comma-separated Yes, if failure mail is to be sent MailLogger.success.to Address(es) to send success messages to, comma-separated Yes, if success mail is to be sent MailLogger.failure.subject Subject of failed build No, default "Build Failure" MailLogger.success.subject Subject of successful build No, default "Build Success" MailLogger.properties.file Filename of properties file that will override other values. No
ant -logger org.apache.tools.ant.listener.MailLogger
AnsiColorLogger The AnsiColorLogger adds color to the standard Ant output by prefixing and suffixing ANSI color code escape sequences to it. It is just an extension of DefaultLogger and hence provides all features that DefaultLogger does.
AnsiColorLogger differentiates the output by assigning different colors depending upon the type of the message.
If used with the -logfile option, the output file will contain all the necessary escape codes to display the text in colorized mode when displayed in the console using applications like cat, more, etc.
This is designed to work on terminals that support ANSI color codes. It works on XTerm, ETerm, Win9x Console (with ANSI.SYS loaded.), etc.
NOTE: It doesn't work on WinNT even when a COMMAND.COM console loaded with ANSI.SYS is used.
If the user wishes to override the default colors with custom ones, a file containing zero or more of the custom color key-value pairs must be created. The recognized keys and their default values are shown below:
AnsiColorLogger.ERROR_COLOR=2;31 AnsiColorLogger.WARNING_COLOR=2;35 AnsiColorLogger.INFO_COLOR=2;36 AnsiColorLogger.VERBOSE_COLOR=2;32 AnsiColorLogger.DEBUG_COLOR=2;34Each key takes as value a color combination defined as Attribute;Foreground;Background. In the above example, background value has not been used.
This file must be specfied as the value of a system variable named ant.logger.defaults and passed as an argument using the -D option to the java command that invokes the Ant application. An easy way to achieve this is to add -Dant.logger.defaults= /path/to/your/file to the ANT_OPTS environment variable. Ant's launching script recognizes this flag and will pass it to the java command appropriately.
Format:
AnsiColorLogger.*=Attribute;Foreground;BackgroundAttribute is one of the following:
0 -> Reset All Attributes (return to normal mode) 1 -> Bright (Usually turns on BOLD) 2 -> Dim 3 -> Underline 5 -> link 7 -> Reverse 8 -> HiddenForeground is one of the following:
30 -> Black 31 -> Red 32 -> Green 33 -> Yellow 34 -> Blue 35 -> Magenta 36 -> Cyan 37 -> WhiteBackground is one of the following:
40 -> Black 41 -> Red 42 -> Green 43 -> Yellow 44 -> Blue 45 -> Magenta 46 -> Cyan 47 -> White ant -logger org.apache.tools.ant.listener.AnsiColorLoggerLog4jListener Passes build events to Log4j, using the full classname's of the generator of each build event as the category:
build started / build finished - org.apache.tools.ant.Project target started / target finished - org.apache.tools.ant.Target task started / task finished - the fully qualified classname of the task message logged - the classname of one of the above, so if a task logs a message, its classname is the category used, and so on. All start events are logged as INFO. Finish events are either logged as INFO or ERROR depending on whether the build failed during that stage. Message events are logged according to their Ant logging level, mapping directly to a corresponding Log4j level.
ant -listener org.apache.tools.ant.listener.Log4jListener
XmlLogger Writes all build information out to an XML file named log.xml, or the value of the XmlLogger.file property if present, when used as a listener. When used as a logger, it writes all output to either the console or to the value of -logfile. Whether used as a listener or logger, the output is not generated until the build is complete, as it buffers the information in order to provide timing information for task, targets, and the project.
By default the XML file creates a reference to an XSLT file "log.xsl" in the current directory; look in ANT_HOME/etc for one of these. You can set the property ant.XmlLogger.stylesheet.uri to provide a uri to a style sheet. this can be a relative or absolute file path, or an http URL. If you set the property to the empty string, "", no XSLT transform is declared at all.
ant -listener org.apache.tools.ant.XmlLogger ant -logger org.apache.tools.ant.XmlLogger -verbose -logfile build_log.xml
Writing your own See the Build Events section for developers.
Notes:
A listener or logger should not write to standard output or error - Ant captures these internally and may cause an infinite loop.