Ant : As Build Tool :: Understanding target

• Understanding target
• Example

<target name="X">
<target name="Y" depends="X">
<target name="Z" depends="X">
<target name="A" depends="Y,Z">

• Now, suppose we execute Target A that depends on Y,Z
• Y depends on X
• Z depends on X
• So first X will get executed then Y and then Z and finally A

Sample of build.xml

<?xml version="1.0"?>
<project name="myfirstAntProject" default="mytarget2">

	<target name="init">
		<echo>Running Target init</echo>
	</target>

	<target name="mytarget1" depends="init">
		<echo>Runnig target mytarget1</echo>
	</target>

	<target name="mytarget2" depends="mytarget1">
		<echo>Runnig target mytarget2</echo>
	</target>

</project>

Output

F:\antExample\Example4>ant
Buildfile: F:\antExample\Example4\build.xml

init:
     [echo] Running Target init

mytarget1:
     [echo] Runnig target mytarget1

mytarget2:
     [echo] Runnig target mytarget2

BUILD SUCCESSFUL
Total time: 2 seconds

F:\antExample\Example4>

Executing individual target by specifying name

//no target named "target2", so generating error
F:\antExample\Example4>ant target2
Buildfile: F:\antExample\Example4\build.xml

BUILD FAILED
Target "target2" does not exist in the project "myfirstAntProject".

Total time: 0 seconds

//running target "mytarget1"
F:\antExample\Example4>ant mytarget1
Buildfile: F:\antExample\Example4\build.xml

init:
     [echo] Running Target init

mytarget1:
     [echo] Runnig target mytarget1

BUILD SUCCESSFUL
Total time: 0 seconds

F:\antExample\Example4>

Circular dependencies

<?xml version="1.0"?>
<project name="myfirstAntProject" default="mytarget2">

	<target name="mytarget1" depends=" mytarget2 ">
		<echo>Runnig target mytarget1</echo>
	</target>

	<target name="mytarget2" depends="mytarget1">
		<echo>Runnig target mytarget2</echo>
	</target>

</project>

Output

F:\antExample\Example4>ant
Buildfile: F:\antExample\Example4\build.xml

BUILD FAILED
Circular dependency: mytarget2 <- mytarget1 <- mytarget2

Total time: 0 seconds

F:\antExample\Example4>

If you have different name, you can run as below

Output

F:\antExample\Example4>ant
Buildfile: build.xml does not exist!
Build failed

F:\antExample\Example4>ant -f mybuild.xml
Buildfile: F:\antExample\Example4\mybuild.xml

init:
     [echo] Running Target init

mytarget1:
     [echo] Runnig target mytarget1

mytarget2:
     [echo] Runnig target mytarget2

BUILD SUCCESSFUL
Total time: 1 second

F:\antExample\Example4>

Create two .java file with following name in src folder

Calculator.java

package com.javaskool;

class Calculator
{
	public void Add(int a,int b)
	{
		System.out.println("Addition : "+(a+b));

	}
}

TestDrive.java

package com.javaskool;

class TestDrive 
{
	public static void main(String[] args) 
	{
		System.out.println("Ant Example");
		Calculator s1=new Calculator();
		s1.Add(45,89);

	}
}

build.xml

<?xml version="1.0"?>
<project name="firstJavaProject" default="jar">

<!--
* compile the java sources
* create a jar file
* execute
-->
<target name="clean">
	<delete dir="build/classes"/>
</target>

<target name="init" depends="clean">
	<mkdir dir="build/classes" />
</target>

<target name="compile" depends="init">
	<javac srcdir="src" destdir="build/classes" />
</target>

<target name="jar" depends="compile">
	<jar destfile="firstAntApp-1.0.jar" basedir="build/classes">
		<manifest>
			<attribute name="Main-Class" value="com.javaskool.TestDrive"/>
		</manifest>
	</jar>
</target>

</project>

Follow the screen commands for Output

//build.xml and src folder in current directory as below
F:\antExample\Example2>dir
 Volume in drive F is workspace
 Volume Serial Number is E846-4436

 Directory of F:\antExample\Example2

20-04-2014  17:06    <DIR>          .
20-04-2014  17:06    <DIR>          ..
20-04-2014  17:06               630 build.xml
20-04-2014  17:06    <DIR>          src
               1 File(s)            630 bytes
               3 Dir(s)   5,008,269,312 bytes free

//Files in src folder

F:\antExample\Example2>dir src
 Volume in drive F is workspace
 Volume Serial Number is E846-4436

 Directory of F:\antExample\Example2\src

20-04-2014  17:06    <DIR>          .
20-04-2014  17:06    <DIR>          ..
20-04-2014  17:02               135 Calculator.java
20-04-2014  17:03               193 TestDrive.java
               2 File(s)            328 bytes
               2 Dir(s)   5,008,265,216 bytes free

//Running ant , will automatically read build.xml

F:\antExample\Example2>ant
Buildfile: F:\antExample\Example2\build.xml

clean:

init:
    [mkdir] Created dir: F:\antExample\Example2\build\classes

compile:
    [javac] F:\antExample\Example2\build.xml:18: warning: 'includeantruntime' wa
s not set, defaulting to build.sysclasspath=last; set to false for repeatable bu
ilds
    [javac] Compiling 2 source files to F:\antExample\Example2\build\classes

jar:
      [jar] Building jar: F:\antExample\Example2\firstAntApp-1.0.jar

BUILD SUCCESSFUL
Total time: 7 seconds

F:\antExample\Example2>java -jar firstAntApp-1.0.jar
'java' is not recognized as an internal or external command,
operable program or batch file.

//Setting Jdk path
F:\antExample\Example2>set PATH=C:\Program Files\Java\jdk1.7.0_03\bin;.;

//Executing java code using created jar file by ant.
F:\antExample\Example2>java -jar firstAntApp-1.0.jar
Ant Example
Addition : 134

F:\antExample\Example2>