我正在调用使用 macrodef
定义的 Ant 任务,但我发现 fail
任务的退出状态未正确传达到 shell。
以下是 SSCCE:
Ant 文件:
<project>
<macrodef name="ff">
<sequential>
<fail message="some failure" status="3"/>
</sequential>
</macrodef>
<ff/>
</project>
调用:
$ ant
Buildfile: /[...]/build.xml
BUILD FAILED
[...]build.xml:10: The following error occurred while executing this line:
[...]build.xml:5: some failure
Total time: 0 seconds
构建如预期失败;但退出状态不正确:
$ echo $?
1
即 Ant
退出时状态为 1 而不是 3。只有当 fail
任务包装在 macrodef
中时才会发生这种情况。
最佳答案
初步猜测可以从 the documentation of the fail
task 获得关于 status
属性:
Exit using the specified status code; assuming the generated Exception is not caught, the JVM will exit with this status.
这正是使用宏定义时发生的情况:fail
任务退出构建时抛出的 BuildException
被捕获宏定义。最终,宏定义会抛出某种包装异常,它会吞掉退出代码。
在 Debug模式下运行 Ant 时,您还可以从异常堆栈跟踪中看到这一点:
使用宏定义:
some failure
at org.apache.tools.ant.taskdefs.Exit.execute(Exit.java:164)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:291)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.taskdefs.Sequential.execute(Sequential.java:68)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:291)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.taskdefs.MacroInstance.execute(MacroInstance.java:398)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:291)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.Target.execute(Target.java:390)
at org.apache.tools.ant.Target.performTasks(Target.java:411)
at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1399)
at org.apache.tools.ant.Project.executeTarget(Project.java:1368)
at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:41)
at org.apache.tools.ant.Project.executeTargets(Project.java:1251)
at org.apache.tools.ant.Main.runBuild(Main.java:809)
at org.apache.tools.ant.Main.startAnt(Main.java:217)
at org.apache.tools.ant.launch.Launcher.run(Launcher.java:280)
at org.apache.tools.ant.launch.Launcher.main(Launcher.java:109)
注意堆栈跟踪中的 MacroInstance
类(第 398 行)调用的方法。通过查看这一行的 Ant 代码,您可以看到一个 try-catch
block ,它捕获 fail
抛出的异常:
try {
c.perform();
} catch (BuildException ex) {
if (this.macroDef.getBackTrace()) {
throw ProjectHelper.addLocationToBuildException(ex, getLocation());
}
ex.setLocation(getLocation());
throw ex;
}
在 catch
block 中,在以下行中抛出新异常:
throw ProjectHelper.addLocationToBuildException(ex, getLocation());
这会导致原始 BuildException
的退出代码被忽略。
更进一步,我们可以看到,如果启用了 this.macroDef.getBackTrace()
,则会抛出此包装器异常。因此,解决该问题的方法是在macrodef中将backtrace
参数设置为false
:
<macrodef name="ff" backtrace="false">
<sequential>
<fail message="some failure" status="3"/>
</sequential>
</macrodef>
关于java - Macrodef 未正确传达退出状态,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27470890/