java.lang.LinkageError：Grails项目中加载器约束违规

Question

我已经构建了一个包含POI（包含poi-3.7和poi-ooxml-3.7）的Grails项目。我已经将这两个外部库添加到我的项目的BuildConfig.groovy文件中的依赖项中。编译它时没有什么奇怪的。但是，当我打电话命令“运行程序”该项目，以低于堆栈跟踪中出现错误：

Base Directory: <path-to-my-project> 
Resolving dependencies... 
Dependencies resolved in 5546ms. 
Running script D:\_TOOLS\STS\grails-1.3.5\scripts\RunApp.groovy 
Environment set to development 
Running Grails application.. 
2011-05-23 18:51:01,225 [main] ERROR context.GrailsContextLoader - Error executing bootstraps: java.lang.LinkageError: loader constraint violation: loader (instance of <bootloader>) previously initiated loading for a different type with name "org/w3c/dom/DOMConfiguration" 
org.codehaus.groovy.runtime.InvokerInvocationException: java.lang.LinkageError: loader constraint violation: loader (instance of <bootloader>) previously initiated loading for a different type with name "org/w3c/dom/DOMConfiguration" 
    at grails.spring.BeanBuilder.invokeBeanDefiningClosure(BeanBuilder.java:723) 
    at grails.spring.BeanBuilder.beans(BeanBuilder.java:573) 
    at grails.spring.BeanBuilder.invokeMethod(BeanBuilder.java:519) 
    at org.grails.tomcat.TomcatServer.start(TomcatServer.groovy:212) 
    at grails.web.container.EmbeddableServer$start.call(Unknown Source) 
    at RunApp$_run_closure5_closure12.doCall(RunApp:158) 
    at RunApp$_run_closure5_closure12.doCall(RunApp) 
    at _GrailsSettings_groovy$_run_closure10.doCall(_GrailsSettings_groovy:280) 
    at _GrailsSettings_groovy$_run_closure10.call(_GrailsSettings_groovy) 
    at RunApp$_run_closure5.doCall(RunApp:149) 
    at RunApp$_run_closure5.call(RunApp) 
    at RunApp.runInline(RunApp:116) 
    at RunApp.this$4$runInline(RunApp) 
    at RunApp$_run_closure1.doCall(RunApp:59) 
    at RunApp$_run_closure1.doCall(RunApp:33) 
    at gant.Gant$_dispatch_closure5.doCall(Gant.groovy:381) 
    at gant.Gant$_dispatch_closure7.doCall(Gant.groovy:415) 
    at gant.Gant$_dispatch_closure7.doCall(Gant.groovy) 
    at gant.Gant.withBuildListeners(Gant.groovy:427) 
    at gant.Gant.this$2$withBuildListeners(Gant.groovy) 
    at gant.Gant$this$2$withBuildListeners.callCurrent(Unknown Source) 
    at gant.Gant.dispatch(Gant.groovy:415) 
    at gant.Gant.this$2$dispatch(Gant.groovy) 
    at gant.Gant.invokeMethod(Gant.groovy) 
    at gant.Gant.executeTargets(Gant.groovy:590) 
    at gant.Gant.executeTargets(Gant.groovy:589) 

Caused by: java.lang.LinkageError: loader constraint violation: loader (instance of <bootloader>) previously initiated loading for a different type with name "org/w3c/dom/DOMConfiguration" 
    at java.lang.Class.getDeclaredMethods0(Native Method) 
    at java.lang.Class.privateGetDeclaredMethods(Class.java:2427) 
    at java.lang.Class.getDeclaredMethods(Class.java:1791) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at org.codehaus.groovy.util.LazyReference.getLocked(LazyReference.java:46) 
    at org.codehaus.groovy.util.LazyReference.get(LazyReference.java:33) 
    at grails.spring.DynamicElementReader.invokeMethod(DynamicElementReader.groovy:121) 
    ... 26 more 

这里是我的配置：

dependencies { 
     provided ('com.oracle:ojdbc6_g:11.2.0.1.0') 
     runtime ('org.apache.poi:poi:3.7', 'org.apache.poi:poi-ooxml:3.7') 
    } 

我该怎么做才能让解决这个？非常感谢！

Answer 1

这是我们终于来了几个小时后来回来的修复。简而言之，从poi中排除xmlbeans，并删除违规类的另一个xmlbeans jar。这是煽动邪恶联系错误的咒语。

• 修改BuildConfig.groovy

    dependencies { 
     compile ('org.apache.poi:poi-ooxml:3.6') {excludes "xmlbeans"} 
    } 

• 提取的xmlbeans

  CD〜
  的mkdir xmlbeantmp
  CD xmlbeantmp
  CP〜/ .ivy2 /缓存/组织。 apache.xmlbeans /的xmlbeans /罐/的xmlbeans-2.3.0.jar 。
  罐XF的xmlbeans-2.3.0.jar
  

• 拆下犯罪类包

  CD有机
  室射频W3C/
  

• 重新创建罐子

  CD ../
  rm xmlbean-2.3.0.jar
  jar cf xmlbean-2.3.0。罐子*
  

• 罐子复制到项目的lib

  CP的XMLBean-2.3.0.jar your_grails_project/lib中/。
  

• 显示爱

  点击答案向上箭头。 :)

Answer 2

我不知道这是否会解决您的问题，但我的猜测是，您对POI的依赖可能应该是编译时。尝试更改您的依赖关系：

dependencies { 
    provided ('com.oracle:ojdbc6_g:11.2.0.1.0') 
    compile ('org.apache.poi:poi:3.7', 'org.apache.poi:poi-ooxml:3.7') 
} 

Answer 3

POI的依赖项（xmlbeans）和grails之间存在冲突。您可以按如下排除：

dependencies { 
    compile('org.apache.poi:poi-ooxml:3.7') { excludes "xmlbeans" } 
} 

以下链接是在追查问题有用：

• http://markmail.org/message/ojglzgft57ts4dgw
• http://jira.grails.org/browse/MAVEN-22

Answer 4

我也有类似的问题，这是缓存问题。我删除了.grails和.ivy2目录（在主目录下），它解决了我的麻烦。祝你好运。

Answer 5

我想我解决了这个问题。 史蒂夫沃尔的解决方案在Grails 2.0.0上不适合我，因为“grails run-app”期间的Perm gen space /内存不足。

BuildConfig.groovy

.... 
inherits("global") { 
    excludes 'xmlbeans', 'xbean' 
} 
.... 
runtime 'xmlbeans:xmlpublic:2.1.0' 
runtime 'org.apache.poi:poi-ooxml:3.7' 
.... 

然后下载xbean-2.1.0.jar，并申请史蒂夫墙解决方案：

jar xf xbean-2.1.0.jar 
cd org 
rm -rf w3c/ 
cd .. 
rm xbean-2.1.0.jar 
jar cf xbean-2.1.0.patched.jar * 
cp xbean-2.1.0.patched.jar your_grails_project/lib/ 

对我来说它工作正常！祝你好运！