这与.有关.我正在尝试使用Grape动态添加maven-ant-tasks jar,模拟这个：
<taskdef uri="antlib:org.apache.maven.artifact.ant"
resource="org/apache/maven/artifact/ant/antlib.xml"
classpathref="ant.classpath" />
我试过使用Grape.grab()来为AntBuilder提供maven-ant-tasks,如下所示：
import groovy.grape.Grape println "grab..." Grape.grab(group:'ant',module:'ant',version:'1.7.0',classLoader:this.class.classLoader.rootLoader) Grape.grab(group: 'org.apache.maven',module: 'maven-ant-tasks',version: '2.0.9') println "ant taskdef..." def ant = new AntBuilder() ant.taskdef (resource: "org/apache/maven/artifact/ant/antlib.xml" )
但这不起作用,因为Grape将模块添加到与ANT引擎正在使用的不同的ClassLoader中.所以,我接受了this AntBuilder classpath question的建议,让Grape使用了根ClassLoader：
import groovy.grape.Grape println "grab..." Grape.grab(group:'ant',version: '2.0.9',classLoader: this.class.classLoader.rootLoader) println "ant taskdef..." def ant = new AntBuilder() ant.taskdef (resource: "org/apache/maven/artifact/ant/antlib.xml" )
现在它抛出一个LinkageError：
Caught: : java.lang.LinkageError: loader constraint violation: when resolving overridden method "org.apache.tools.ant.helper.ProjectHelper2$RootHandler.setDocumentLocator(Lorg/xml/sax/Locator;)V" the class loader (instance of org/codehaus/groovy/tools/RootLoader) of the current class,org/apache/tools/ant/helper/ProjectHelper2$RootHandler,and its superclass loader (instance of <bootloader>),have different Class objects for the type org/xml/sax/Locator used in the signature at test.mavenanttasks.run(mavenanttasks.groovy:11)
有关使此工作的任何提示？或者,整个事情是个坏主意吗？
解决方法
我发现了这个：
http://groovy.codehaus.org/Using+Ant+Libraries+with+AntBuilder
首先,将maven-ant-tasks放在根类加载器中：
@Grapes([ @Grab(group = 'org.apache.maven',module = 'maven-ant-tasks',version = '2.1.3'),@GrabConfig(systemClassLoader = true) ])
或者,对于旧版本的Groovy：
Grape.grab(group: 'org.apache.maven',version: '2.1.3',classLoader: this.class.classLoader.rootLoader)
Maven ANT任务是一个’AntLib’,它们可以像这样加载：
import groovy.xml.NamespaceBuilder def ant = new AntBuilder() def mvn = NamespaceBuilder.newInstance(ant,'antlib:org.apache.maven.artifact.ant')
