04-23 16:21:33.695: E/AndroidRuntime(32266): FATAL EXCEPTION: AsyncTask #1
04-23 16:21:33.695: E/AndroidRuntime(32266): java.lang.RuntimeException: An error occured while executing doInBackground()
04-23 16:21:33.695: E/AndroidRuntime(32266): at android.os.AsyncTask$3.done(AsyncTask.java:200)
04-23 16:21:33.695: E/AndroidRuntime(32266): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
04-23 16:21:33.695: E/AndroidRuntime(32266): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
04-23 16:21:33.695: E/AndroidRuntime(32266): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
04-23 16:21:33.695: E/AndroidRuntime(32266): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
04-23 16:21:33.695: E/AndroidRuntime(32266): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
04-23 16:21:33.695: E/AndroidRuntime(32266): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
04-23 16:21:33.695: E/AndroidRuntime(32266): at java.lang.Thread.run(Thread.java:1096)
04-23 16:21:33.695: E/AndroidRuntime(32266): Caused by: java.lang.NoClassDefFoundError: org.apache.http.entity.mime.MultipartEntity
04-23 16:21:33.695: E/AndroidRuntime(32266): at com.agilemobi.collect.android.tasks.DataUploaderTask.doInBackground(DataUploaderTask.java:122)
04-23 16:21:33.695: E/AndroidRuntime(32266): at com.agilemobi.collect.android.tasks.DataUploaderTask.doInBackground(DataUploaderTask.java:1)
04-23 16:21:33.695: E/AndroidRuntime(32266): at android.os.AsyncTask$2.call(AsyncTask.java:185)
04-23 16:21:33.695: E/AndroidRuntime(32266): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
04-23 16:21:33.695: E/AndroidRuntime(32266): ... 4 more
以前出現過很多次這種錯誤了，一般是環境變量的配置有問題，或者jar包間存在依賴，或者jar包沒有直接bulid path加到項目中來
以上問題，我android工程都沒出現
org.apache.http.entity.mime.MultipartEntity這個類實現了org.apache.http.HttpEntity接口，該接口在android.jar中
MultipartEntity類在httpmime-4.0.jar中，已經build path加到libraries下，還是會出現上述錯誤，實在令人費解。
後面解決的辦法是httpmime-4.0.jar所在的lib 右鍵選擇 Use as Source Folder
這樣，jar包直接當做源文件加到工程下，在bin下就可以看到對應jar文件，項目裏就能直接引用jar中的類。
我發現如果是bulid path加進去的jar包不會在bin下編譯成class文件，如果引用就報出上面的錯誤。