Java 无法使用类加载器 AntClassLoader[] 找到 ant taskdef 类
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ant taskdef class cannot be found using the classloader AntClassLoader[]
提问by Nyahaha Wakoko
I'm developing an eclipse plugin that will run an Ant XML file programatically.
I used org.apache.tools.ant.helper.ProjectHelperImpland org.apache.tools.ant.Projectthen parse the Ant XML file and run a specific target, in this case test.
My Ant XML file looks like this:
我正在开发一个 eclipse 插件，它将以编程方式运行 Ant XML 文件。
我使用org.apache.tools.ant.helper.ProjectHelperImpl并org.apache.tools.ant.Project解析 Ant XML 文件并运行特定目标，在本例中为test.
我的 Ant XML 文件如下所示：
<!-- project class path -->
<path id="projectClassPath">
<fileset dir="${basedir}/jars">
<include name="**/*.jar" />
</fileset>
</path>
<!-- task definitions -->
<taskdef file="${basedir}/tasks.properties">
<classpath refid="projectClassPath" />
</taskdef>
<!-- test custom ant task -->
<target name="test" description="test target">
<customTask />
</target>
<!-- test echo -->
<target name="testEcho" description="test echo target">
<echo message="this is a test."/>
</target>
The tasks.properties file looks like this:
tasks.properties 文件如下所示：
customTask=my.custom.task.CustomTask
My java code that runs the Ant file programatically:
我以编程方式运行 Ant 文件的 java 代码：
Project ant = new Project();
ProjectHelperImpl helper = new ProjectHelperImpl();
MyDefaultLogger log = new MyDefaultLogger();
ant.init();
helper.parse(ant, antXml);
log.setMessageOutputLevel(Project.MSG_VERBOSE);
ant.addBuildListener(log);
ant.executeTarget(testTarget);
Running the target testmanually, is fine, but running the testtarget programatically displays this error:
test手动运行目标很好，但以test编程方式运行目标会显示此错误：
taskdef class my.custom.task.CustomTask cannot be found using the classloader AntClassLoader[]
If I will also be executing the file programatically without the project class path, task definitionsand test custom ant taskit will run successfully.
My assumption is that, when running the Ant file programatically, it did not register the classpath somehow?
EDIT:
multiple target name testchanged <!-- test echo -->target name to testEcho. (credits to: @smooth reggae)
如果我也将是没有编程执行文件project class path，task definitions并且test custom ant task它会成功运行。
我的假设是，当以编程方式运行 Ant 文件时，它没有以某种方式注册类路径？
编辑：
多个目标名称test将<!-- test echo -->目标名称更改为testEcho. （归功于：@smooth 雷鬼）
采纳答案by Nyahaha Wakoko
I have managed to fix my error, I changed my Java implementation of calling the Ant XML file, and it worked like a charm.
My Java code looks like this:
我已经设法修复了我的错误，我更改了调用 Ant XML 文件的 Java 实现，并且它的工作非常出色。
我的 Java 代码如下所示：
// get the default custom classpath from the preferences
AntCorePreferences corePreferences = AntCorePlugin.getPlugin().getPreferences();
URL[] urls = corePreferences.getURLs();
// get the location of the plugin jar
File bundleFile = FileLocator.getBundleFile(myPlugin.getBundle());
URL url = bundleFile.toURI().toURL();
// bond urls to complete classpath
List<URL> classpath = new ArrayList<URL>();
classpath.addAll(Arrays.asList(urls));
classpath.add(url);
AntRunner runner = new AntRunner();
// set custom classpath
runner.setCustomClasspath(classpath.toArray(new URL[classpath.size()]));
// set build file location
runner.setBuildFileLocation(xmlFile.getAbsolutePath());
// set build logger
runner.addBuildLogger(MyDefaultLogger.class.getName());
// set the specific target to be executed
runner.setExecutionTargets(new String[] { "test" });
// run
runner.run();
