AntCallback总是返回相同的值

Question

我的问题是;
当我多次调用一个antcallback函数时，它总是返回相同的值。查看下面的代码:

<project name="AntCallBack" default="testFnc" basedir=".">
   <taskdef resource="net/sf/antcontrib/antcontrib.properties" />
   <target name="acbFnc" description="Sub Function" >
      <echo message="[acbFnc] started"/>
      <property name="out.file" value="${in.file}"/>
      <echo message="[acbFnc] ended."/>
   </target>
   <target name="testFnc" description="Main" >
        <antcallback target="acbFnc" return="out.file" >
            <param name="in.file" value="TEST-1" />
        </antcallback>
        <echo message="CALL - 1 : out.file : ${out.file}" />
        <antcallback target="acbFnc" return="out.file" >
            <param name="in.file" value="TEST-2" />
        </antcallback>
        <echo message="CALL - 2 : out.file : ${out.file}" />
    </target>
</project>

结果是:

$ /home/apache-ant-1.9.4/bin/ant -f AntCallBackTest.xml
Buildfile: AntCallBackTest.xml
testFnc:
acbFnc:
     [echo] [acbFnc] started
     [echo] [acbFnc] ended.
     [echo] CALL - 1 : out.file : TEST-1
acbFnc:
     [echo] [acbFnc] started
     [echo] [acbFnc] ended.
     [echo] CALL - 2 : out.file : TEST-1
BUILD SUCCESSFUL
Total time: 0 seconds

如你所见，我发送了"param name="in。文件" value="TEST-1" "第一次调用，
然后我输入param name=。文件" value="TEST-2" "在第二次调用，
但是它总是返回第一个值:
CALL - 1: out。file: TEST-1
CALL - 2: out。file: TEST-1

我做错了什么?
提前感谢

Answer 1

我找到了解决方案:
我必须在第二次调用之前取消变量设置:

<var name="out.file" unset="true"/>

我的意思是，它应该是这样的:

<target name="testFnc" description="Main" >
    <antcallback target="acbFnc" return="out.file" >
        <param name="in.file" value="TEST-1" />
    </antcallback>
    <echo message="CALL - 1 : out.file : ${out.file}" />
    <var name="out.file" unset="true"/>
    <antcallback target="acbFnc" return="out.file" >
        <param name="in.file" value="TEST-2" />
    </antcallback>
    <echo message="CALL - 2 : out.file : ${out.file}" />
</target>