Many great things from the Java ecosystem do work when brought over to Android: Guava, Jackson, GSON, Joda-Time are some common libaries that are pure Java. Dagger is an Android library implemented in pure Java that is starting to work its way back into 'regular Java'. And of course the tools like IntelliJ, ProGuard, Maven, Gradle are all from the Java ecosystem.
But many of the best things are not compatible. The Android Gradle plugin has a different interface than the Java Gradle plugin, so other existing Gradle plugins (this one being an example) all have to be re-written specifically for Android. Even some of the seemingly obvious ones like pure Java/JUnit 4 testing on x86 are impossible. Some Java 7 syntax is available on Android, but the major SDK improvements like the new file I/O API are not. Nothing from Java 8 is available, including blocks and the new time API.
In light of the recent advances by Apple on the tooling & language front, Google needs to decide if half-baked Java compatibility is worth the cost of being handcuffed. Either go all-in on Java, pay whatever Oracle wants and get full Java 8 compatibility now, or fork out on their own and move faster.