Xref Aosp [best] -

Download the desired AOSP branch using repo:

AOSP generates IDE project files natively.

matches file names containing the specified string. Searching for "Activity" in File Path reveals every source file with "Activity" in its name, such as Activity.java , ActivityManager.java , or ActivityThread.java .

Stop grepping. Start cross-referencing. Your future self will thank you when you find that obscure AudioPolicyManager bug in 30 seconds instead of three hours. xref aosp

Great for scripting or quick checks.

Technically, xref in AOSP raises interesting trade-offs. A comprehensive index must balance completeness against noise. Naive cross-referencing that surfaces every textual match will overwhelm; smarter systems require semantic awareness — symbol resolution, build-context sensitivity, and knowledge of generated artifacts. They must understand the build graph so references point not just to source files, but to the concrete artifact and configuration that matter at runtime. Performance matters too: a developer’s flow is broken if queries take minutes. So, engineering choices around incremental updates, caching, and language-aware parsers shape adoption.

Provides powerful search capabilities for finding specific code snippets across the entire AOSP repository. Download the desired AOSP branch using repo: AOSP

: Searching the latest master branch and specific official releases. Key Feature

当你需要查阅老版本的 Android 代码（如 Android 5.0 Lollipop 或 6.0 Marshmallow），或者你更习惯 OpenGrok 那种纯粹的搜索逻辑时，可以使用该工具。

当官方 cs.android.com 由于网络原因访问较慢，或者你需要同时对比 Android 9 到 Android 13 区间的新版本代码时，AOSPXRef 是一个非常优秀的备选方案。 Stop grepping

# On Ubuntu/Debian sudo apt install opengrok universal-ctags

Are you trying to understand the of a specific AOSP sub-project? Share public link