XStream NoClassDefFoundError(XStream NoClassDefFoundError)

 在这一天的大部分时间里，我一直在撞墙。 我将xstream-1.4.2添加到java构建路径并从我的代码中调用它没有问题： 
 
XStream yyz = new XStream();
String str_xml = yyz.toXML(ld_data);
 
 一切都编译但是当执行到达上面的第一行（XStream实例化）时，我得到下面的堆栈跟踪中看到的错误。 在我看来，这个错误表明它无法找到XStream对象，但它的智能感知和编译是gtg。 我在Eclipse中用来添加外部文件的步骤是： 
 
 右键单击项目>构建路径>配置构建路径。 
 
 在左侧的Java Build Path右侧，选择Libraries选项卡。 
 
 在右键单击Add External jar's，然后浏览到XStream文件并添加它。 点击确定然后跑进了错误？ 
 
 致命异常：主要java.lang.NoClassDefFoundError：com.thoughtworks.xstream.XStream at org.gpgvm.ironmike.IcyArmActivity.onOptionsItemSelected（IcyArmActivity.java:166）at android.app.Activity.onMenuItemSelected（Activity.java:2205）at com.android.internal.view中的com.android.internal.policy.impl.PhoneWindow.onMenuItemSelected（PhoneWindow.java:748）位于com.android.internal.view的com.android.internal.view.menu.MenuItemImpl.invoke（MenuItemImpl.java:143）。 menu.MenuBuilder.performItemAction（MenuBuilder.java:855）at com.android.internal.view.menu.IconMenuView.invokeItem（IconMenuView.java:532）at com.android.internal.view.menu.IconMenuItemView.performClick（IconMenuItemView。 java：122）在android.view.View.Handler.dispatchMessage（Handler.java:92）的android.view.View $ PerformClick.run（View.java:9080）android.os.Handler.handleCallback（Handler.java:587） ）在android.app.Looper.loop（Looper.java:123）的android.app.ActivityThread.main（ActivityThread.java:3683）java.lang.reflect.Method.invokeNative（Native Method）at java.lang 位于com.android.internal.os.ZygoteInit.main（ZygoteInit.java）的com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:839）中的.reflect.Method.invoke（Method.java:507） ：597）at dalvik.system.NativeStart.main（Native Method） 
 
 
 引起：java.lang.ClassNotFoundException：com.thoughtworks.xstream.XStream 
 
 
 在dalvik.system.PathClassLoader.findClass（PathClassLoader.java:240）中的装载程序dalvik.system.PathClassLoader [/data/app/org.gpgvm.ironmike-2.apk]中的java.lang.ClassLoader.loadClass（ClassLoader.java） ：551）在java.lang.ClassLoader.loadClass（ClassLoader.java:511）... 17更多 
 
 关于我缺少什么的任何想法？ JB 

I've been beating my head against the wall most of the day on this one. I added the xstream-1.4.2 to java build path and call it from my code no problems:
 
XStream yyz = new XStream();
String str_xml = yyz.toXML(ld_data);
 
Everything compiles but when the execution reaches the first line above (XStream instantiation) I get the error seen in the stack trace below. The error seems to me to indicate that it can't find the XStream object yet it does as intellisense and compilation are gtg. The steps I used in Eclipse to add the external file are:
 
right click project > Build Path > Configure Build Path.
 
On the left Java Build Path on the right select the Libraries tab.
 
On the right click the Add External jar's and then browsed to XStream file and added it. Hit OK and ran smack into the error??
 
FATAL EXCEPTION: main java.lang.NoClassDefFoundError: com.thoughtworks.xstream.XStream at org.gpgvm.ironmike.IcyArmActivity.onOptionsItemSelected (IcyArmActivity.java:166) at android.app.Activity.onMenuItemSelected(Activity.java:2205) at com.android.internal.policy.impl.PhoneWindow.onMenuItemSelected (PhoneWindow.java:748) at com.android.internal.view.menu.MenuItemImpl.invoke (MenuItemImpl.java:143) at com.android.internal.view.menu.MenuBuilder.performItemAction (MenuBuilder.java:855) at com.android.internal.view.menu.IconMenuView.invokeItem (IconMenuView.java:532) at com.android.internal.view.menu.IconMenuItemView.performClick (IconMenuItemView.java:122) at android.view.View$PerformClick.run(View.java:9080) at android.os.Handler.handleCallback(Handler.java:587) at android.os.Handler.dispatchMessage(Handler.java:92) at android.os.Looper.loop(Looper.java:123) at android.app.ActivityThread.main(ActivityThread.java:3683) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:507) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:839) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) at dalvik.system.NativeStart.main(Native Method)
 
 
Caused by: java.lang.ClassNotFoundException: com.thoughtworks.xstream.XStream 
 
 
in loader dalvik.system.PathClassLoader[/data/app/org.gpgvm.ironmike-2.apk] at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:240) at java.lang.ClassLoader.loadClass(ClassLoader.java:551) at java.lang.ClassLoader.loadClass(ClassLoader.java:511) ... 17 more
 
Any ideas as to what I'm missing? JB

原文：https://stackoverflow.com/questions/10956358