我試圖運行一個Java類作爲我的項目部署(我想在部署時創建一些資源,然後可以在運行時讀取)。使用maven運行項目的java類從屬性
大多數情況下,我使用maven構建循環 - 尤其是依賴管理。
這是我得到的;創建一個路徑(run),並使用maven ant任務添加maven的依賴關係,然後運行一個調用java類(MyClass)的目標,該類已被編譯到目標\ src目錄中的... MyClass.class ,使用該目錄的類路徑和上面指定的運行路徑。
<path id="run" />
<artifact:dependencies pathid="run">
<artifact:pom file="pom.xml" id="my_project" />
</artifact:dependencies>
<target name="runMyClass">
<java classname="...MyClass" fork="yes" maxmemory="512M" append="true">
<classpath>
<pathelement location="target\classes"/>
<pathelement id="run" />
</classpath>
</java>
</target>
我知道目標\類是正確的 - 如果我註釋掉除了運行的路徑,它找到了類,但報告說,一些在類的進口不可用的類路徑上。
然而,當我運行它,我得到以下堆棧跟蹤:
C:\somepath\my_project\build.xml:118: java.lang.NullPointerException
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:116)
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)
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 com.intellij.rt.ant.execution.AntMain2.main(AntMain2.java:32)
Caused by: java.lang.NullPointerException
at org.apache.tools.ant.types.resources.FileResourceIterator.addFiles(FileResourceIterator.java:104)
at org.apache.tools.ant.types.resources.FileResourceIterator.<init>(FileResourceIterator.java:95)
at org.apache.tools.ant.types.Path$PathElement.iterator(Path.java:124)
at org.apache.tools.ant.types.resources.Union.getCollection(Union.java:123)
at org.apache.tools.ant.types.resources.Union.getCollection(Union.java:107)
at org.apache.tools.ant.types.resources.BaseResourceCollectionContainer.cacheCollection(BaseResourceCollectionContainer.java:265)
at org.apache.tools.ant.types.resources.BaseResourceCollectionContainer.iterator(BaseResourceCollectionContainer.java:142)
at org.apache.tools.ant.types.Path.iterator(Path.java:710)
at org.apache.tools.ant.types.resources.Union.getCollection(Union.java:123)
at org.apache.tools.ant.types.resources.Union.list(Union.java:86)
at org.apache.tools.ant.types.Path.list(Path.java:378)
at org.apache.tools.ant.types.Path.addExisting(Path.java:331)
at org.apache.tools.ant.types.Path.addExisting(Path.java:319)
at org.apache.tools.ant.types.Path.concatSpecialPath(Path.java:572)
at org.apache.tools.ant.types.Path.concatSystemClasspath(Path.java:532)
at org.apache.tools.ant.types.CommandlineJava.haveClasspath(CommandlineJava.java:647)
at org.apache.tools.ant.types.CommandlineJava.addCommandsToList(CommandlineJava.java:437)
at org.apache.tools.ant.types.CommandlineJava.getCommandline(CommandlineJava.java:405)
at org.apache.tools.ant.types.CommandlineJava.describeCommand(CommandlineJava.java:482)
at org.apache.tools.ant.taskdefs.Java.checkConfiguration(Java.java:176)
at org.apache.tools.ant.taskdefs.Java.execute(Java.java:107)
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)
... 16 more
對我來說,這看起來像一個例外是在螞蟻的代碼被扔在添加路徑設置爲的過程classpath,但我可能是錯的。
任何人都可以提出(以下任一):
我怎麼可能會去有關調試呢?
另一種方法來做我想做的事情(上面描述的 )?
如果我能對這500次投票,我會:p。 –