在 https://github.com/zxing/zxing 下载二维码扫描
将 android 导入，code打成jar包运行时 报
06-14 23:43:08.690: E/AndroidRuntime(7761): FATAL EXCEPTION:
main
06-14 23:43:08.690: E/AndroidRuntime(7761):
java.lang.ExceptionInInitializerError
06-14
23:43:08.690: E/AndroidRuntime(7761): at
java.lang.Class.newInstanceImpl(Native Method)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
java.lang.Class.newInstance(Class.java:1429)
06-14 23:43:08.690:
E/AndroidRuntime(7761): at
android.app.Instrumentation.newActivity(Instrumentation.java:1021)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2577)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
android.app.ActivityThread.access$2300(ActivityThread.java:125)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
android.os.Handler.dispatchMessage(Handler.java:99)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
android.os.Looper.loop(Looper.java:123)
06-14 23:43:08.690:
E/AndroidRuntime(7761): at
android.app.ActivityThread.main(ActivityThread.java:4627)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
java.lang.reflect.Method.invokeNative(Native Method)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
java.lang.reflect.Method.invoke(Method.java:521)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:863)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:621)
06-14
23:43:08.690: E/AndroidRuntime(7761): at
dalvik.system.NativeStart.main(Native Method)
06-14
23:43:08.690: E/AndroidRuntime(7761): Caused by: java.lang.NoClassDefFoundError:
com.google.zxing.ResultMetadataType
06-14 23:43:08.690:
E/AndroidRuntime(7761): at
com.google.zxing.client.android.CaptureActivity.<clinit>(CaptureActivity.java:107)
06-14
23:43:08.690: E/AndroidRuntime(7761): ... 15 more
解决
在eclipse中 Properties -> Java Build Path -> "Order and Export"
在Order and Export选项卡中将core.jar提前到第一位 并选中它
然后clean你的工程,这一步非常重要，千万别忘记了。
重新编译运行就可以了
如果还是报 妹的，就换ecplise版本把，可能是ecplise自身的bug
找不到 com.google.zxing.ResultMetadataType 异常解决
原文：http://www.cnblogs.com/elena76/p/3553900.html