I am trying to assign two different strings to two different variables dependent on two booleans in Ant.
Pseudocode (ish):
if(condition)
if(property1 == null)
property2 = string1;
property3 = string2;
else
property2 = string2;
property3 = string1;
What I've tried is;
<if>
<and>
<not><isset property="property1"/></not>
<istrue value="${condition}" />
</and>
<then>
<property name="property2" value="string1" />
<property name="property3" value="string2" />
</then>
<else>
<property name="property2" value="string2" />
<property name="property3" value="string1" />
</else>
</if>
But i get a null pointer exception for the line containing "<if>". I can get it to work using <condition property=...> tags but can only set one property at a time. I tried using <propertyset> but that wasn't allowed either.
I'm new to ant as you will probably have guessed :).
Gav
There are several ways to do this. The most straightforward is to just use two condition statements, and take advantage of property immutability:
<condition property="property2" value="string1">
<isset property="property1"/>
</condition>
<condition property="property3" value="string2">
<isset property="property1"/>
</condition>
<!-- Properties in ant are immutable, so the following assignments will only
take place if property1 is *not* set. -->
<property name="property2" value="string2"/>
<property name="property3" value="string1"/>
This is a bit cumbersome and doesn't scale well, but for just two properties I would probably use this approach.
A somewhat better way is to use a conditional target:
<target name="setProps" if="property1">
<property name="property2" value="string1"/>
<property name="property3" value="string2"/>
</target>
<target name="init" depends="setProps">
<!-- Properties in ant are immutable, so the following assignments will only
take place if property1 is *not* set. -->
<property name="property2" value="string2"/>
<property name="property3" value="string1"/>
<!-- Other init code -->
</target>
We are again taking advantage of property immutability here. If you don't want to do that, you can use the unless attribute, and an extra level of indirection:
<target name="-set-props-if-set" if="property1">
<property name="property2" value="string1"/>
<property name="property3" value="string2"/>
</target>
<target name="-set-props-if-not-set" unless="property1">
<property name="property2" value="string2"/>
<property name="property3" value="string1"/>
</target>
<target name="setProps" depends="-set-props-if-set, -set-props-if-not-set"/>
<target name="init" depends="setProps">
<!-- Other init code -->
</target>
It is important to note that the if and unless attributes of target only check if the property is set, not the value of the property.
You can use Ant-Contrib library to have access to a neat <if><then><else> syntax, however it will require a few download/install steps.
See this other SO question: ant-contrib - if/then/else task
Related
I am trying to check a folder's name, and if it contains a certain string, I want that folder path to be changed.
So far I came up with this:
<property name="component.release.dir" value="${install.dir}/${component.name}" />
<!-- Check if the component is a part of projectL -->
<condition property="projectLFolderSpotted">
<matches pattern="projectL" string="${component.release.dir}"/>
<!-- if so, put the component in an appropriate folder -->
<property name="component.release.dir" value="${install.dir}/projectL/${component.name}" />
<echo message="projectL component has been detected, and moved accordingly!"/>
</condition>
But I get the following error:
condition doesn't support the nested "property" element.
Is there a way to achieve this?
Thanks in advance.
Properties in ANT are immutable, once they're assigned a value it doesn't change.
Here's how I'd suggest you do it:
<project name="demo" default="build">
<property name="release.dir.seed" location="build/helloworld"/>
<condition property="release.dir" value="build/found/helloworld" else="build/notfound/helloworld">
<contains string="${release.dir.seed}" substring="helloworld"/>
</condition>
<target name="build">
<echo message="Result: ${release.dir}"/>
</target>
</project>
In Ant, how can I test if a property ends with a given value?
For example
<property name="destdir"
value="D:\FeiLong Soft\Essential\Development\repository\org\springframework\spring-beans" />
how can I test if ${destdir} ends with "spring-beans"?
additional：
In my ant-contrib-1.0b3.jar, without 'endswith' task~~
You can test if ${destdir} ends with "spring-beans" like this (assuming you have ant-contrib, and are using Ant 1.7 or later).
<property name="destdir" value="something\spring-beans" />
<condition property="destDirHasBeans">
<matches pattern=".*spring-beans$" string="${destdir}" />
</condition>
<if>
<equals arg1="destDirHasBeans" arg2="true" />
<then>
$destdir ends with spring-beans ...
</then>
<else> ...
</else>
</if>
The '$' in the regex pattern ".*spring-beans$" is an anchor to match at the end of the string.
As Matteo, Ant-Contrib contains a lot of nice stuff, and I use it heavily.
However, in this case can simply use the <basename> task:
<basename property="basedir.name" file="${destdir}"/>
<condition property="ends.with.spring-beans">
<equals arg1="spring-beans" arg2="${basedir.name}"/>
<condition>
The property ${ends.with.spring-beans} will contain true if ${destdir} ends with string-beans and false otherwise. You could use it in the if or unless parameter of the <target> task.
You can use the EndWith condition from Ant-Contrib
<endswith string="${destdir}" with="spring-beans"/>
For example
<if>
<endswith string="${destdir}" with="spring-beans"/>
<then>
<!-- do something -->
</then>
</if>
Edit
<endswith> is part of the Ant-Contrib package that has to be installed and enabled with
<taskdef resource="net/sf/antcontrib/antlib.xml"/>
The JavaScript power can be used for string manipulation in the ANT:
<script language="javascript"> <![CDATA[
// getting the value for property sshexec.outputproperty1
str = project.getProperty("sshexec.outputproperty1");
// get the tail , after the separator ":"
str = str.substring(str.indexOf(":")+1,str.length() ).trim();
// store the result in a new property
project.setProperty("res",str);
]]> </script>
<echo message="Responce ${res}" />
Hi all this is my code for target calling.
<target name="abc">
<var name="x" value="10"/>
<antcall target="def"/>
<!--Again Access The value of x here and also change it here-->
</target>
<target name="def">
<!--Access The value of x here and also change it here-->
</target>
and also i want to access this X in other build file,is there any way
This is not possible with ant. In an properties are immutable and cannot be reset. The var task from ant contrib can be used to override values, but should be used sparingly.
You could use a temporary file to achieve what you want. But probably you are trying something weird, which can be solved in a different way.
This would also work across buildfiles if they have access to the property file.
<target name="abc">
<var name="x" value="10"/>
<antcall target="def"/>
<!--Again Access The value of x here and also change it here-->
<var unset="true" file="myproperty.properties" /> <!-- read variable from property file-->
</target>
<target name="def">
<echo file="myproperty.properties" append="false">x=12</echo> <!-- create a new propertyfile-->
</target>
For the sake of justice, there is a hack that allows to alter ant's immutable properties without any additional libs (since java 6):
<scriptdef name="propertyreset" language="javascript"
description="Allows to assing #{property} new value">
<attribute name="name"/>
<attribute name="value"/>
project.setProperty(attributes.get("name"), attributes.get("value"));
</scriptdef>
Usage:
<target name="abc">
<property name="x" value="10"/>
<antcall target="def"/>
</target>
<target name="def">
<propertyreset name="x" value="11"/>
</target>
As #oers mentioned, this should be used with care after all canonical approaches proved not to fit.
It is difficult to suggest further without knowing the goal behind the question.
I'm trying to refactor an Ant buildfile with many similar targets into a buildfile that uses macros. This roughly is what it looks like:
<macrodef name="build-text">
<argument name="lang" />
<element name="file-list"/>
<sequential>
<property name="lang" value="#{lang}" />
<xslt style="my_stylesheet.xsl" destdir="build" basedir="src">
<!-- lots of params here -->
<file-list />
</xslt>
</sequential>
</macrodef>
<target name="buildTextDE">
<build-text lang="DE">
<file-list>
<mapper>
<mapper type="glob" from="Text1_${lang}.html" to="Text1_${lang}.fo"/>
<mapper type="glob" from="Text2_${lang}.html" to="Text2_${lang}.fo"/>
</mapper>
</file-list>
</build-text>
</target>
There is another task called buildTextEN that is nearly identical except for the lang attribute. In some cases, the file list differs however. Now how would I like to simplify the buildfile further by defining a "global" mapping list that contains the file lists for German and English, each file with the placeholder for the language. I would like to reference this global mapping where no special case is needed. How would I do that?
Say that I need to do something like:
<copy todir="${DEPLOYMENT_DIR}" overwrite="true">
<fileset dir="dir1" />
<fileset dir="dir2" />
<fileset dir="dir3" />
...
<if>
<equals arg1="${SPECIAL_BUILD}" arg2="true"/>
<then>
<fileset dir="dir7" />
<fileset dir="dir8" />
...
</then>
</if>
</copy>
(The real task is not copy, I'm just using it to illustrate the point.)
Ant will complain that my task doesn't support nested <if> which is fair enough. I've been thinking along these lines:
I could add a macrodef with an "element" attribute like this:
<macrodef name="myCopy">
<element name="additional-path" />
<sequential>
<copy todir="${DEPLOYMENT_DIR}" overwrite="true">
<fileset dir="dir1" />
<fileset dir="dir2" />
<fileset dir="dir3" />
...
<additional-path/>
</copy>
</sequential>
</macrodef>
But that would mean that the caller (target) must specify the additional path which I want to avoid (if many targets call this task, they would have to repeat the fileset definitions in the additional-path element).
How to code the additional filesets inside the macrodef so that Ant doesn't complain?
AntContrib has an Ant FileSet object augmented with if and unless conditions.
http://ant-contrib.sourceforge.net/fileset.html
if Sets the property name for the 'if' condition. The fileset will be
ignored unless the property is
defined. The value of the property is
insignificant, but values that would
imply misinterpretation ("false",
"no") will throw an exception when
evaluated.
unless Set the property name for the 'unless' condition. If named
property is set, the fileset will be
ignored. The value of the property is
insignificant, but values that would
imply misinterpretation ("false",
"no") of the behavior will throw an
exception when evaluated.
You could use it like this:
<copy todir="${DEPLOYMENT_DIR}" overwrite="true">
<fileset dir="dir1" />
<fileset dir="dir2" />
<fileset dir="dir3" />
...
<fileset dir="dir7" if="SPECIAL_BUILD" />
<fileset dir="dir8" if="SPECIAL_BUILD" />
</copy>
One way (not sure if a good one) to achieve that is to create two macrodefs - one "public" for general use and one "internal" that does the real work and is intended to be called only from the "public" macro. Like this:
<macrodef name="task-for-public-use">
<sequential>
<if>
<equal arg1="${SPECIAL_BUILD}" arg2="true" />
<then>
<internal-task>
<additional-path>
...
</additional-path>
</internal-task>
</then>
<else>
<internal-task ... />
</else>
</if>
</sequential>
</macrodef>
<macrodef name="internal-task">
<element name="additional-path" />
<sequential>
<copy ...>
...
<additional-path/>
</copy>
</sequential>
</macrodef>
I don't like it much though and hope there's a better way.