Ant: How to know if at least one copy task from ten copy tasks actually copied a file

问题

I have a target which has several copy tasks; It basically copies the common jars to our set of applications from a centralized location to the lib folder of the application.
Seeing as this is a regular copy task a jar will be copied only if it is newer than the one currently in the lib folder.
This is the relevant part in the build.xml:

<target name="libs"/>  
  <copy file=... />  
  <copy file=... />  
  <copy file=... />  
  <antcall target="clean_compiled_classes"/>  
</target>  
<target name="clean_compiled_classes" if="anyOfTheLibsWereCopied">  
  <delete .../>  
</target>

I'm looking for a way to set the anyOfTheLibsWereCopied property before the ant call in the libs target based on whether or not any of the files has been actually changed.

Thanks,
Ittai

回答1:

I would advise having a look at the Uptodate task. I have never used it before but I guess what you are trying to do will be implemented along the following lines:

<target name="libs"/>
  <uptodate property="isUpToDate">
    <srcfiles dir="${source.dir}" includes="**/*.jar"/>
    <globmapper from="${source.dir}/*.jar" to="${destination.dir}/*.jar"/>
  </uptodate>
  <!-- tasks below will only be executed if
       there were libs that needed an update -->
  <antcall target="copy_libs"/>  
  <antcall target="clean_compiled_classes"/>  
</target>

<target name="copy_libs" unless="isUpToDate">  
  <copy file=... />  
  <copy file=... />  
  <copy file=... />
</target>

<target name="clean_compiled_classes" unless="isUpToDate">  
  <delete .../>
</target>

Your other option would be to implement your own ant task that does what you want. This would require a bit more work though.

来源：https://stackoverflow.com/questions/4533925/ant-how-to-know-if-at-least-one-copy-task-from-ten-copy-tasks-actually-copied-a

标签

java

ant

copy

if-statement

properties