之前可以编译的项目，突然间编译报下面的错，请问啥原因呢？
UNEXPECTED TOP-LEVEL EXCEPTION:
com.android.dex.DexException: Multiple dex files define Landroid/support/v4/accessibilityservice/AccessibilityServiceInfoCompat$AccessibilityServiceInfoVersionImpl;
at com.android.dx.merge.DexMerger.readSortableTypes(DexMerger.java:594)
at com.android.dx.merge.DexMerger.getSortedTypes(DexMerger.java:552)
at com.android.dx.merge.DexMerger.mergeClassDefs(DexMerger.java:533)
at com.android.dx.merge.DexMerger.mergeDexes(DexMerger.java:170)
at com.android.dx.merge.DexMerger.merge(DexMerger.java:188)
at com.mand.dexer.Main.mergeLibraryDexBuffers(Main.java:439)
at com.mand.dexer.Main.runMonoDex(Main.java:287)
at com.mand.dexer.Main.run(Main.java:230)
at com.mand.dexer.Main.main(Main.java:199)
at com.mand.Main.main(Main.java:103)
FAILED
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':MainActivity:dexDebug'.
> com.mon.internal.LoggedErrorException: Failed to run command:
/Users/zhouzhineng/Documents/dev_tools/mac_software/android-sdk-macosx/build-tools/19.1.0/dx --dex --num-threads=4 --output /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/dex/debug /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/classes/debug /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/dependency-cache/debug /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/asmack-level7-3.1.1-53dffce3576fdc33b3b62152e9764f9ccb3c84b4.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/barchart-udt-bundle-2.3.0-df79d487907a92b78d37dcc40f3d88d627851c3a.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/classes-093dbd2eef18cc8673fb2400c97187dc78859b22.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/classes-3bd4dd73f18e2e6c2b3705c0f1bce8398691109e.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/classes-6d33bb1b746bc4ab56a224e7603145adac384a28.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/classes-90e9000e7e5f8c48b1e181c8a89912636954d3bb.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/commons-codec-1.3-e03649e0660d24d20a884897860cd45f8beb411b.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/cordova-3.0.0rc1-f9b4bfe8188c48a050cc6b879661861865c1f9f6.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/gson-2.2.4-8961ff1bec421f632b098cc9d2439b445918c20a.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/guava-14.0.1-49e96580731106497d52e55ec12f25dd8e9e83b0.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/httpcore-4.1.4-31b814717353cf13e65e45a1684b19b07921c466.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/httpmime-4.1.3-e42f2fbf12f89fcc8f12da368eac72b1f77feec1.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/javassist-3.18.1-GA-531cec526b734d7917b003716b3ccb995dcd1b21.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/json-simple-1.1.1-a2493baf1bdbfbb0edcfef608ce103732ef93070.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/msgpack-0.6.11-afb2c52606cd7544d921983736773fb632a971d2.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/native-libs-89b802a6f0084110d84c143145b7412ccd6164cc.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/netty-buffer-4.0.19.Final-edb06bcf43a16195fdafa5f3b4d062d3ba78730c.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/netty-codec-4.0.19.Final-ade70dc39d9688a8678a298d4cc911789d58832d.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/netty-codec-http-4.0.19.Final-e72d3f55dfd16c03c3ecfacca31e49ec5fd55523.jar /Users/zhouzhineng/Desktop/chameleon/MainActivity/build/intermediates/pre-dexed/debug/netty-common-4.0.19.Final-f38d0e369e5359b3326ef154f360f377d600b103.jar /Users/zhouzhineng/Des
