I need to modify a (xml-)file from Apache Ant. "loadfile" task allows to load the file's content in a property. But how to store the property's value back to a file after its (property) modification?
Of course I could write custom task to perform this operation but I would like to know if there's some existing implementation.
You can use the echo task.
<echo file="${fileName}" message="${xmlProperty}"/>
The echoxml task might be of interest to you as well.
Use propertyfile task. An example taken from ant manual:
<propertyfile file="my.properties">
<entry key="abc" value="${abc}"/>
</propertyfile>
This may be better than echo as it updates the properties file with a given value, while echo appends to or overwrites the whole file.
Related
I have an Ant buildfile (build.xml) which is called by some application. I would like to know exactly what kind of properties are used to invoke Ant. Therefore I would like to modify the build.xml file to display all properties specified in the call, e.g.:
ant aTarget -Dxslt.parser=SAXON -Dbasedir=aFolder
would display list as below
- target: aTarget
- xslt.parser = SAXON
- basedir=aFolder
Please note that I do not know exactly what is being using to invoke Ant. Therefore, I need to use some sort of a loop get all properties, options.
The simplest thing that comes to mind is to place a line like:
<echo message="Ant invocation is '${sun.java.command}'" />
In the buildfile outside of any target. It'll look something like:
% ant aTarget -Dx=y
[echo] ant invocation is: 'org.apache.tools.ant.launch.Launcher -cp . aTarget -Dx=y'
It shows you what was passed to the Ant Launcher, which might will likely be a little more than what was passed to the ant wrapper script, but should do.
I would avoid trying to parse the line, as you say, you don't know what might be there, and it could quickly get complicated.
Take a look at the <echoproperties> task:
<property name="in.file.prop" value="value2"/>
<echoproperties/>
in.file.prop and its value will be printed. However, over 60 other properties will be printed as well including properties built into Ant.
You can save the results of <echoproperties> to a file and then filter that file with something like a <linecontains> filter.
I have file abc.txt and i need to check that file exists in suppose
c:\test\abc.txt location
If true then I need to print some message else I need to perform some operation.
Best is to use ant <available ../> to fill a property and then either using ant-contrib <if> task or create separate targets that run depending on the property value.
Check this answer for details: Ant task to run an Ant target only if a file exists?
Is it possible to change ant property location attribute with .properties file like
property value attribute?
ant.xml
<property name="images" location="some_location" />
ant.properties
name=D:\images
See ant manual propertyfile => there is no attribute called location.
The location attribute from property task is only a 'special' case of a value, that knows how to deal with absolute and relative pathes.
If you need to edit | overwrite existing property values(locations) use either :
ant script task (groovy or groovy task recommended)
or some Ant addon like Flaka or Antcontrib, providing tasks for that purpose.
Declaring a property within the build file will override the same value imported from a properties file.
The only way to do this is setting the property value on the command-line as follows:
ant -Dimages=D:\images
<propertyfile file="${build.dir}/MyProperties.properties">
<entry key="releaseInformation"
type="string"
value="${build.time}"/>
</propertyfile>
When Ant copies my properties file over to the bin directory there is a property in it that has something like "samplePathName=C\:\Users\SomeUser\". But the property from the original file was "samplePathName=C:\Users\SomeUser\". How would the additional backslash end up there? I don't see anything that could possibly cause this to happen. Where should I begin looking other than the build.xml which only contains (relevant) the above line?
This is a common problem - the format of property files is defined by Sun (Oracle). Ant is conforming to this, which is why the escaping happens. There's no way round this using the propertyfile task - that's the way it's intended to work. If the file is genuinely a Java property file, then it shouldn't matter - the escaping should be handled correctly when the file is read.
However if you are hoping to use propertyfile to write a name-value config file that's for something else - where the escaping is not wanted - you'll need to adopt a different approach. As mentioned in the answer to a related question - you might use the Ant replace or replaceregexp tasks for this.
I am reading a file in ant and loading the properties through loadproperties. I am interested in using the value of a specific property, whose name is not known. I know that it follows a pattern because that is how I load the property.
I can echoproperties and see that it is being loaded.
But I dont know how to access its value, given that its name is actually a pattern rather that hardcoded.
How can I access this property's value to do some processing.
I hope this is clear. Please ask if I need to clarify some more.
Take a look at ant-contrib package. Its propertycopy task will do what you need. If you need to resolve an arbitrary number of properties following an established pattern, you would use ant-contrib's propertycopy in conjunction with ant-contribs "for" task.
http://ant-contrib.sourceforge.net/tasks/tasks/index.html
You should use Ant's script task.
I suggest using the beanshell script since it is pure java.
For example, to print all properties for your project, use the following:
<target name="echoprops">
<script language="beanshell">
System.out.println("All Properties: " + project.getProperties().keySet());
</script>
</target>
It should be easy to modify the above script to get the property you want.
To use this task, you will need to run the following in $ANT_HOME first:
ant -f fetch.xml script -Ddest=user
That will download all required optional jars to ~/.ant/lib .