On running the following command:
ant targetname -Dk1=v1 -Dk2=v2
I want the command line parameters passed down to java, like java whatever -Dk1=v1 -Dk2=v2.
I need to access these parameters from Java code with System.getProperty or System.getenv.
What do I need to write in my ant build script to make this happen?
Or should I take some other approach altogether?
I'm not sure exactly how you want to pass these values, but there are several mechanisms:
Use <sysproperty> to pass system properties you need to set:
Use <arg> to pass command line arguments to your Java class
Use <jvmarg> to pass arguments to your Java command itself
If you fork your Java task, you can also set environment variables too. These are ignored if you don't fork the Java task
This:
$ foo=bar; java -Xlingc com.example.foo.bar -Dsys1=fu -Dsys2=barfu -arg1 -arg2 bar
Becomes:
<java classname="com.example.foo.bar"
fork="true">
<env key="foo" value="bar"/>
<sysproperty key="sys1" value="fu"/>
<sysproperty key="sys2" value="barfu"/>
<jvmarg value="-Xlingc"/>
<arg value="-arg1"/>
<arg value="-arg2"/>
<arg value="bar"/>
</java>
Hope that example helps
Not good in Ant Script but I do something like below :
<target name="execute">
<echo> Running MyClass ......... </echo>
<java classname="pkg.MyClass" classpathref="libs">
<arg value="val1" /> <!-- command line args -->
<arg value="val2" />
<arg value="val3" />
<env key="k1" value="v1" /> <!-- set environmental value -->
</java>
</target>
If you are using Eclipse, you will get suggestions in popup under java tag. I got few more like : <sysproperty/>, <syspropertyset></syspropertyset>, <jvmarg/>
Use the nested <arg> elements in your <java> task:
<java classname="test.Main">
<arg value="${k1}"/>
<arg value="${k2}"/>
<classpath>
<pathelement location="dist/test.jar"/>
<pathelement path="${java.class.path}"/>
</classpath>
</java>
Related
I am using ant exec command to implement the less utility to view the source code of a bunch of .java files. (I know that there are other ways to do this like using concat)
So the call ant view works if I specify only one file:
<target name="view">
<exec executable="less" dir=".">
<arg value="Main.java"/>
</exec>
</target>
But if I change my code to <arg value="*.java"/> to view all files, it actually searches for a file named *.java.
Apparently I can put a bunch of arg's for each file, but is there a way to do this with one arg ?
The * glob is expanded by the shell on Unix-likes, that's why less doesn't do it itself.
Apart from <exec> there is <apply> which works on a resource collection:
<apply executable="less" dir="." parallel="true" relative="true">
<fileset dir="." includes="*.java"/>
</apply>
You can use foreach which requires ant-contrib
<target name="view">
<foreach target="call-less" param="file">
<fileset dir="${src}" includes="**/*.java" />
</foreach>
</target>
<target name="call-less">
<exec executable="less">
<arg value="${file}" />
</exec>
</target>
i have a taskdef pointing to a class
<taskdef name="configjar" classname="com.bea.alsb.tools.configjar.ant.ConfigJarTask" classpathref="configjar.path">
</taskdef>
Inside this i want to pass java system property. Like how we do in the java task
<java >
<sysproperty key="" value""/>
</java>
The problem is the jar is some library which I can't modify .I can't use a command to set in a build environment we have.
I know i can do this by setting ANT_OPTS,but can i do this from build.xml.How can i make this happen
Not sure it's exact way or not. But found a work around for this
<java classname="org.apache.tools.ant.launch.Launcher" fork="true" failonerror="true">
<sysproperty key="weblogic.home" value="${weblogic.home}"/>
<sysproperty key="osb.home" value="${osb.home}"/>
<arg value="test"/>
</java>
<target name="test">
<configjar debug="${task.debug}"
failonerror="${task.failonerror}"
errorProperty="${task.errorproperty}"
settingsFile="${settingsFile}" >
</configjar>
</target>
I have invoked ant using java command and set the two system properties as shown above.
I would like to start Server and the ProxyServer class simultaneously, using Ant tag, is it possible to run the wo classes?
Here is the code I tried but Ant only starts the Server class and does not do anything there after, not sure if there is away in ant to achieve this.
Appreciate your help.
<target name="pxyServer" depends="server">
<echo>Executing Target - Run ProxyServer</echo>
<java classname="pxy.ProxyServer">
<classpath path="staging" />
</java>
</target>
<target name="server">
<echo>Executing Target - RunServer</echo>
<java classname="pxy.Server">
<classpath path="staging" />
</java>
</target>
Your targets are executed sequentially, and since the first one keeps running, the second one never gets the chance to start.
For parallel execution, you can use ant's "parallel" task:
http://ant.apache.org/manual/Tasks/parallel.html
Your modified script should probably look something like this:
<target name="startServerAndProxy">
<echo>Running server and proxy...</echo>
<parallel>
<java classname="pxy.Server">
<classpath path="staging" />
</java>
<java classname="pxy.ProxyServer">
<classpath path="staging" />
</java>
</parallel>
</target>
(Of course, if you're trying to start some third application in parallel, a client for example, then you should also include that one in the "parallel".)
UPDATE:
To start the server and the proxy each in its own console, I don't know if it can be done with the "java" Ant task, but I just tested that it can be done with "exec":
<target name="doit">
<parallel>
<exec executable="cmd" dir="staging">
<arg line="/k start java.exe pxy.Server"/>
</exec>
<exec executable="cmd" dir="staging">
<arg line="/k start java.exe pxy.ProxyServer"/>
</exec>
</parallel>
</target>
I have a compiler (and language) I am building that is normally invoked thus:
java -jar nc.jar \
-p some/referenced/package.nc \
-p framework.nc \
source1.ns source2.ns sourceN.ns \
-o output/package.nc
I'd like to include a task in my ANT build file that invokes the compiler to compile the standard library and all test cases, but specifying each separate compiler invocation as a <java> task is painful:
<target name="framework" depends="compiler" description="Build the n framework">
<!-- More compile steps -->
<java jar="nc.jar" fork="true">
<arg value="-p"/>
<arg path="../nframework/build/n.core.nc"/>
<arg path="../nframework/n/debug/DebugPrint.ns"/>
<arg path="../nframework/n/debug/Trace.ns"/>
<arg value="-o"/>
<arg path="../nframework/build/n.debug.nc"/>
</java>
<!-- More compile steps -->
</target>
I would like to create an ANT task of some sort that can simplify this into something like:
<target name="framework" depends="compiler" description="Build the n framework">
<!-- More compile steps -->
<nc output="../nframework/build/n.debug.nc">
<link-package path="../nframework/build/n.core.nc"/>
<src>
<fileset dir="../nframework/n/debug" includes="**/*.ns"/>
</src>
</nc>
<!-- More compile steps -->
</target>
To this end, I tried macrodef:
<macrodef name="nc">
<attribute name="output"/>
<element name="link-package"/>
<element name="src"/>
<sequential>
<java jar="nc.jar" fork="true">
<arg value="-p"/>
<!-- This doesn't do what I want -->
<link-package/>
<!-- Neither does this -->
<src/>
<arg value="-o"/>
<arg path="#{output}"/>
</java>
</sequential>
</macrodef>
I've tried several variations on the above, but each errors out with something like:
/home/jwarner/code/nlang/nc/build.xml:55: java doesn't support nested "fileset" element.
Is there a way to do this without extending ANT itself? Alternatively, would it be fairly easy to add an ant task to my compiler? I'm not terribly picky about the syntax of the final <nc> task.
I have had a similar problem in the past where the out-of-the-box Ant tasks didn't quite do what I wanted them to do. I found that it was very easy to write my own Ant task.
The documentation is concise but does a good job of explaining what you need to do.
http://ant.apache.org/manual/develop.html#writingowntask
My program getting command line arguments. How can I pass it when I use Ant?
Extending Richard Cook's answer.
Here's the ant task to run any program (including, but not limited to Java programs):
<target name="run">
<exec executable="name-of-executable">
<arg value="${arg0}"/>
<arg value="${arg1}"/>
</exec>
</target>
Here's the task to run a Java program from a .jar file:
<target name="run-java">
<java jar="path for jar">
<arg value="${arg0}"/>
<arg value="${arg1}"/>
</java>
</target>
You can invoke either from the command line like this:
ant -Darg0=Hello -Darg1=World run
Make sure to use the -Darg syntax; if you ran this:
ant run arg0 arg1
then ant would try to run targets arg0 and arg1.
If you do not want to handle separate properties for each possible argument, I suggest you'd use:
<arg line="${args}"/>
You can check if the property is not set using a specific target with an unless attribute and inside do:
<input message="Type the desired command line arguments:" addProperty="args"/>
Putting it all together gives:
<target name="run" depends="compile, input-runargs" description="run the project">
<!-- You can use exec here, depending on your needs -->
<java classname="Main">
<arg line="${args}"/>
</java>
</target>
<target name="input-runargs" unless="args" description="prompts for command line arguments if necessary">
<input addProperty="args" message="Type the desired command line arguments:"/>
</target>
You can use it as follows:
ant
ant run
ant run -Dargs='--help'
The first two commands will prompt for the command-line arguments, whereas the latter won't.
The only effective mechanism for passing parameters into a build is to use Java properties:
ant -Done=1 -Dtwo=2
The following example demonstrates how you can check and ensure the expected parameters have been passed into the script
<project name="check" default="build">
<condition property="params.set">
<and>
<isset property="one"/>
<isset property="two"/>
</and>
</condition>
<target name="check">
<fail unless="params.set">
Must specify the parameters: one, two
</fail>
</target>
<target name="build" depends="check">
<echo>
one = ${one}
two = ${two}
</echo>
</target>
</project>
Can you be a bit more specific about what you're trying to do and how you're trying to do it?
If you're attempting to invoke the program using the <exec> task you might do the following:
<exec executable="name-of-executable">
<arg value="arg0"/>
<arg value="arg1"/>
</exec>
What I did in the end is make a batch file to extract the CLASSPATH from the ant file, then run java directly using this:
In my build.xml:
<target name="printclasspath">
<pathconvert property="classpathProp" refid="project.class.path"/>
<echo>${classpathProp}</echo>
</target>
In another script called 'run.sh':
export CLASSPATH=$(ant -q printclasspath | grep echo | cut -d \ -f 7):build
java "$#"
It's no longer cross-platform, but at least it's relatively easy to use, and one could provide a .bat file that does the same as the run.sh. It's a very short batch script. It's not like migrating the entire build to platform-specific batch files.
I think it's a shame there's not some option in ant whereby you could do something like:
ant -- arg1 arg2 arg3
mpirun uses this type of syntax; ssh also can use this syntax I think.