We cannot run Java Bytecode on Android because: Android uses Dalvik VM(virtual machine) instead of Java VM. To run a Java Bytecode you need JVM( Java Virtual Machine). Java in computers and Android uses a separate environment to run their code.

Can the bytecode be written in Java be run on Android?

Java bytecode in Java Archive (JAR) files is not executed by Android devices. Instead, Java classes are compiled into a proprietary bytecode format and run on Dalvik (or compiled version thereof with newer ART), a specialized virtual machine (VM) designed for Android.

Is it possible to run Java source code directly on Android?

No, it is not possible to run java source code directly on android because, android uses Davik Virtual Machine and not traditional JVM.