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Ant & Jar
Ant – Java-based build tool
Jar – pkzip archive, that contains
metadata (a manifest file) that the
JRE understands
jar
Use jar utility to create jar files
A compressed, tar'd collection of *.class
files
Command format like tar
File format pkzip, but includes a manifest
file MANIFEST.MF (meta-data)
Can be added to classpath; JRE searches a
jarfile like a directory, for included
packages
Creating a jarfile
Options much like tar



c – create
x – extract
u – update
Others



v – verbose
f – specify archive filename
m – include manifest info from named file
Creating a jarfile - example
Given class files:
pokerSuit.class, pokerClient.class
Create the jarfile:
$ jar cvf poker.jar poker*.class
You can use unzip -l to look at the contents. Notice the
MANIFEST.MF:
Archive: poker.jar
Length
Date
Time
-------------0 08-06-06 09:30
120 08-06-06 09:30
670 08-06-06 09:19
636 08-06-06 09:19
-------1426
Name
---META-INF/
META-INF/MANIFEST.MF
pokerClient.class
pokerSuit.class
------4 files
Executing a jarfile
Jar files can be made executable by adding a
Main-Class line to the manifest, and identifying
the class that contains main
create an mf file (poker.mf) w/these lines:
Classpath: ./poker.jar
Main-Class: pokerClient

Create the jarfile w/this info:
$ jar cvfm poker.jar poker.mf *.class

To run:
java –jar poker.jar
Ant
A bit like Make
Cross-platform

Extended w/Java classes, rather than shelldependent scripts
Reads XML configuration files
Java-based
Open source
Why another build tool?
Make tools are shell based
Development across multiple platforms
Ant vs Make
Ant is Cross Platform

Ant will work on any platform that has a Java VM.
Make relies on specific OS shell commands
Syntax



Make has a scary looking syntax
Make tab problem
Ant uses XML
 self documenting
Efficiency
Ant
PROs



Fast Compiles
Platform
Independent
Easier to use than
make

CONs
 non-Java projects
Who should use Ant?
Use Ant


If you don’t already
know make
If you are
developing anything
cross platform

Use Make
–
–
If you are a make
expert.
Developing
applications in nonJava language.
Resources
Ant : the definitive guide

ISBN: 0596001843
Java tools for eXtreme
Programming


ISBN: 047120708X
Electronic resource
Ant add-ons:

http://ant.apache.org/external.
html
Links
http://ant.apache.org/
http://ant.apache.org/resources.html
http://ant.apache.org/manual/index.html

Nice description of the various tags/tasks
Key Words
Build File

Collection of targets (hopefully logical)
Target


Collection of tasks
Can have dependencies (other targets, etc.)
Task

Specific commands for building, running, etc
Ant Details
All Ant tasks are defined in a Java class

An example of a particular task would be
JAVADOC (see common built-in tasks, later)
Ant has a core set of tasks that come with
it. Other optional tasks can be
downloaded.

Ant is very modularized.
build.xml
The default build file Ant looks for
-f option allows to specify a different build
file
How to run ant
ant [-f file] [target*]


file – config file (build.xml if not supplied)
target* - list of targets to be built
E.g.:
$ ant test
$ ant
$ ant compile
If you don’t specify,
the default is
executed
$ ant javadoc
$ ant compile javadoc
build.xml Example
<project default="compile">
<target name="compile">
<javac srcdir="." />
</target>
</project>

Simply compiles all *.java files in the current
directory (calls javac)
Complex ant build file example
<project default="all">
<property name="obj-dir" location="obj" />
<property name="lib-dir" location="lib" />
<property name="src-dir" location="src" />
<target name="init">
<mkdir dir="${obj-dir}" />
<mkdir dir="${lib-dir}" />
</target>
<target name="clean-init">
<delete dir="${obj-dir}" />
<delete dir="${lib-dir}" />
</target>
<target name="compile" depends="init">
<javac srcdir="${src-dir}" destdir="${obj-dir}" />
</target>
<target name="clean-compile">
<delete>
<fileset dir="${obj-dir}" includes="**/*.class" />
</delete>
</target>
Complex example (cont.)
<target name="jar" depends="compile">
<jar destfile="${lib-dir}/hello.jar" basedir="${objdir}" />
</target>
<target name="clean-jar">
<delete file="${lib-dir}/hello.jar" />
</target>
<target name="run" depends="jar">
<java classname="hello"
classpath="${lib-dir}/hello.jar"
fork="true" />
</target>
<target name="all" depends="run"/>
<target name="clean" depends="clean-init"/>
</project>
Ant Setup
Ant is installed in /usr/local/bin/ant
JAVA_HOME variable should be set


should be set to prefix of /bin/java
On the CS machines:
 /usr/local
OR
 /opt/java5/jdk1.5.0_06/
Common Ant Tasks
<javac srcdir=dir [includes=fileList]/>

compiles Java source files
<java classname=class/> OR
<java fork='yes' jar=jar/>

runs a Java application
javadoc

generates javadoc HTML file from Java source files
mkdir

creates a directory and any missing parent
directories
Common Tasks (cont)
move

moves files and directories to a new directory
<copy file=src (tofile=dest | todir=destDir) />
 copies files
<delete (file=file | dir=dir ) />

deletes given file or dir
<echo [file=file] message=msg/> or
<echo [file=file]>msg</echo>
 outputs a message to System.out or file
Common Ant Tasks (cont.)
Gunzip

unzips a GZIP file
Gzip

creates a GZIP file from a file
Jar

creates a JAR file from a set of files
Mail

sends email using SMTP
Get


creates a copy of a remote file at a specified URL
can use http and ftp URLs
Extra Tasks
JUnit


runs JUnit tests
requires junit.jar from http://junit.org
FTP


lists, gets, puts and deletes files on an FTP server
requires NetComponents.jar
Examples
Given files foo.java, which extends bar.java,
in the current directory
compile all java files in directory:
<project default="compile">
<target name="compile">
<javac srcdir="." />
</target>
</project>
Example
compile only foo and bar:
<project default="compile">
<target name="compile" depends='foo,bar'/>
<target name="foo" depends='bar'>
<javac srcdir='./' includes='foo.java'/>
</target>
<target name="bar">
<javac srcdir='./' includes='bar.java'/>
</target>
</project>
Example
Add a "clean" target
<target name="clean">
<delete>
<fileset dir="./">
<include name='*.class'/>
</fileset>
</delete>
</target>
Example
Add a "run" target:
<target name="run" depends='compile'>
<java classname='foo'/>
</target>
Example
Add a target to build a jarfile:
<target name="jar" depends='compile'>
<jar destfile='./foo.jar'
manifest='man.mf'>
<fileset dir='./'>
<include name='*.class'/>
</fileset>
</jar>
</target>
Example
Run the jarfile:
<target name="run" depends='jar'>
<java jar='foo.jar'
fork='true'/>
</target>