java.lang.NoClassDefFoundError: org/apache/poi/xssf/usermodel/XSSFWorkbook

Question

我遇到了这个异常，但我无法理解那里发生了什么。

因为在编译时我的类能够访问 apache POI 类，但在运行时我的类抛出他无法找到的异常

org.apache.poi.xssf.usermodel.XSSFWorkbook。

到目前为止，无论网上提供什么解决方案，我都尝试了所有方法，但不明白我缺少什么。

奇怪的是相同的代码和相同的 Apache POI 库在我朋友的 eclipse 上工作。我们都有相同的项目。不明白那里发生了什么。

我检查了我引用库的所有文件夹的访问权限。

如果您有任何建议，请分享。

我收到以下异常。

!MESSAGE Unhandled event loop exception
!STACK 0
java.lang.NoClassDefFoundError: org/apache/poi/xssf/usermodel/XSSFWorkbook
    at com.herzog.pmide.mergedconfigxml.ui.editors.DocumentGenerator.prepareScadaIOListExcel(DocumentGenerator.java:94)
    at com.herzog.pmide.mergedconfigxml.ui.editors.DocumentGenerator.scadaIOList(DocumentGenerator.java:77)
    at com.herzog.pmide.mergedconfigxml.ui.actions.DocumentGeneratorAction.run(DocumentGeneratorAction.java:47)
    at org.eclipse.ui.internal.PluginAction.runWithEvent(PluginAction.java:253)
    at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:595)
    at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:511)
    at org.eclipse.jface.action.ActionContributionItem$5.handleEvent(ActionContributionItem.java:420)
    at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
    at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4353)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1061)
    at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4172)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3761)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$9.run(PartRenderingEngine.java:1151)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:331)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1032)
    at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:148)
    at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:636)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:331)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:579)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
    at com.herzog.pmide.application.Application.start(Application.java:20)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:380)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:235)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:648)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:603)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1465)
    at org.eclipse.equinox.launcher.Main.main(Main.java:1438)
Caused by: java.lang.ClassNotFoundException: org.apache.poi.xssf.usermodel.XSSFWorkbook cannot be found by com.herzog.pmide.mergedconfigxml.ui_1.0.0.qualifier
    at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:432)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:345)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:337)
    at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:160)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

MANIFEST.MF 如下

    Manifest-Version: 1.0
Bundle-ManifestVersion: 2
Bundle-Name: Ui
Bundle-SymbolicName: com.herzog.pmide.mergedconfigxml.ui;singleton:=true
Bundle-Version: 1.0.0.qualifier
Bundle-Activator: com.herzog.pmide.mergedconfigxml.ui.Activator
Bundle-Vendor: Example
Require-Bundle: org.eclipse.ui,
 org.eclipse.core.runtime,
 org.eclipse.core.resources,
 org.eclipse.emf.ecore.xmi,
 org.eclipse.emf.edit.ui,
 com.herzog.pmide.machinelib.model.edit,
 org.eclipse.ui.forms,
 org.eclipse.ui.workbench,
 org.eclipse.ui.ide,
 com.herzog.pmide.mergedconfigxml.model.edit,
 org.eclipse.gef,
 com.herzog.pmide.tools.importutility,
 com.herzog.pmide.machinelib.model,
 org.eclipse.swt,
 org.eclipse.emf.query,
 com.herzog.pmide.mergedconfigxml.model,
 org.eclipse.ui.editors,
 org.eclipse.emf.validation,
 org.eclipse.emf.validation.ui,
 org.slf4j.api,
 org.junit,
 org.eclipse.emf.compare,
 org.eclipse.emf.compare.edit,
 org.eclipse.emf.compare.ide.ui,
 org.eclipse.compare,
 org.apache.commons.io,
 org.eclipse.core.filesystem,
 de.vonloesch.pdf4Eclipse,
 de.vonloesch.pdf4eclipse.help,
 com.herzog.pmide.routingline.model
Bundle-ActivationPolicy: lazy
Bundle-ClassPath: .
Export-Package: com.herzog.pmide.mergedconfigxml.ui,
 com.herzog.pmide.mergedconfigxml.ui.editors.unitconfig,
 com.herzog.pmide.mergedconfigxml.ui.views
Bundle-Localization: OSGI-INF/l10n/message

build.properties 如下

source.. = src/
output.. = bin/
bin.includes = META-INF/,\
               .,\
               plugin.xml,\
               icons/,\
               OSGI-INF/l10n/message.properties

Answer 1

插件只能访问其他插件或插件中包含的 jar 中的类，这些 jar 包含在 bundle 类路径中。设置 Java 构建路径属性不会正确配置插件。

将你需要的所有 jars 添加到插件中，通常这些都放在一个 'lib' 目录中。

更新 build.properties 以将这些 jars 包含在“bin.includes”部分中。例如：

source.. = src/
output.. = bin/
bin.includes = META-INF/,\
               .,\
               plugin.properties,\
               plugin.xml,\
               lib/,\
               lib/jogg-0.0.7.jar,\
               lib/jorbis-0.0.15.jar,\
               lib/vorbisspi1.0.2.jar

我在 lib 目录中有 3 个 jars（这些不是 POI jars，这只是我的一个项目中的一个示例）。

更新 MANIFEST.MF 并设置 Bundle-Classpath 以包含罐子。您可以在“类路径”部分的“运行时”选项卡中的 MANIFEST.MF 编辑器中执行此操作（使用列表右侧的添加...按钮并选择插件中的库）。一定要留下'.'的条目。您的 MANIFEST.MF 最终应该包含一个 `Bundle-Classpath' 条目，如下所示：

Bundle-ClassPath: .,
 lib/jogg-0.0.7.jar,
 lib/jorbis-0.0.15.jar,
 lib/vorbisspi1.0.2.jar