---
id: android
title: Troubleshooting Android Issues
sidebar_label: Android Issues
custom_edit_url: https://www.internalfb.com/intern/diffusion/FBS/browsefile/master/xplat/sonar/docs/android.mdx
---

Flipper is a work in progress and issues may occur. This page contains known issues associated with the Android platform and provides steps you can take to try to resolve them.

## Exception from call site #4 bootstrap method

Build error after including the Flipper dependency:

```
Exception from call site #4 bootstrap method
```

This can happen because we include [OkHttp3](https://github.com/square/okhttp/issues/4597#issuecomment-461204144) as dependency which makes use of Java 8 features. There are two ways of dealing with this:

**Enable Java 8 support**

Add this to your Gradle config:

```groovy
android {
  compileOptions {
    targetCompatibility = "8"
    sourceCompatibility = "8"
   }
 }
 ```

 **Exclude the OkHttp3 dependency**

 Alternatively, if you don't plan on making use of OkHttp, you can exclude the dependency from the build entirely:

 ```
debugImplementation('com.facebook.flipper:flipper:*') {
  exclude group: 'com.squareup.okhttp3'
}
```

## Duplicate class `com.facebook.jni.*`

This can occur when mixing different versions of [FBJNI](https://github.com/facebookincubator/fbjni),
a library we use to interact with native C++ code.

Speficially, this can happen when the versions `0.0.x` and `0.1.x` are mixed. Version `0.1.0` of FBJNI
switched to using [Google Prefab](https://google.github.io/prefab/) for distributing native artifacts,
which made the split into combined, "java-only" and "header" packages redundant and only requires
a single dependency in your projects.

When including both "fbjni-java-only:0.0.1" and "fbjni:0.1.0" in one project, you will now
duplicate class errors during the build process. You must ensure that only one of the two
versions is used in your entire dependency tree. Start by looking at `./gradlew :myapp:dependencies`
to see where the different version requirements come from. Then exclude the FBJNI dependency from
one of them, e.g.

```groovy
implementation("com.facebook.react:react-native:+") {
    exclude group:'com.facebook.fbjni'
}
```