Android-unable to execute Dex:multiple Dex files define

This hint means that the referenced file is duplicated. In the reference JSON parsing library, when clean works, the error says:

Unable to execute Dex:multiple Dex files define Lorg/apache/commons/collections/buffer;

Conversion to Dalvik format failed:unable to execute dex:multiple Dex files define Lorg/apache/commons/collections/buffe R

Later look carefully, the original Commons-beanutils-1.7.0.jar and Commons-collections-3.2.jar have Org.apache.commons.collections.Buffer.class .

Android-unable to execute Dex:multiple Dex files define