Android DexClassLoader sample, dynamicly load code . Note: The paul/example/dynamic/DynamicTest.java is for compiling .jar file which is finally converted to .dex file. This .dex file is placed in assets folder. You can compile DynamicTest.java to .dex file yourself. What's more important, When test dynamic loading class, please delete the DynamicTest.java, or you will get an error.