psv psv - 6 months ago 13
Android Question

What is dex in Gradle

What is the dex in gradle or in Android ?

In Gradle, what's the meaning of


Sometimes my project does not compile because of some dexerrors.
I need to activate proguard to compile my android app.


In the standard java world:

When you compile standard java code : the compiler produce *.class file. A *class file contains standard java bytecode that can be executed on a standard JVM.

In the Android world:

It is different. You use the java language to write your code, but the compiler don't produce *.class files, it produce *.dex file. A *.dex file contains bytecode that can be executed on the Android Virtual Machine (dalvik) and this is not a standard Java Virtual Machine.

To be clear: a dex file in android is the equivalent of class in standard java.

So dexoptions is a gradle object where some options to configure this java-code-to-android-bytecode transformation are defined. The options configured via this object are :

  • targetAPILevel
  • force-jumbo mode (when enabled it allows a larger number of strings in the dex files)

To enable jumboMode :

android {
    dexOptions {
        jumboMode = true