GitHub - flyfishxu/Kadb: A Kotlin Multiplatform library to connect Android devices directly without ADB binary file.

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Kadb is a Kotlin Multiplatform ADB client library for talking directly to adbd.

It is intended for apps and tools that need shell, sync, install, pairing, or port forwarding without embedding the full adb CLI or server stack.

Overview

  • Direct Kotlin API for adbd
  • Android and JVM targets
  • Android and desktop JVM USB connections, wireless pairing, shell, file transfer, install, and TCP forwarding
  • AOSP-aligned host behavior where practical

Powered by Kadb

Kadb powers WearOS Toolbox, an Android smartwatch toolbox for connecting to watches, managing apps, and transferring files. Both Kadb and WearOS Toolbox are developed by Flyfish Studio.

Installation

dependencies {
    implementation("com.flyfishxu:kadb:2.1.5")
}

Optional mDNS discovery:

dependencies {
    implementation("com.flyfishxu:kadb-mdns:2.1.5")
}

Quick Start

Connect to an existing device transport:

Kadb.create("127.0.0.1", 5555).use { kadb ->
    val response = kadb.shell("echo hello")
    check(response.exitCode == 0)
    check(response.output == "hello\n")
}

Pair with a new Android 11+ device:

Kadb.pair("10.0.0.175", 37755, "643102")

Discover wireless debugging endpoints with the optional mDNS artifact:

val mdns = KadbMdnsAndroid(context)
mdns.start()
val mdns = KadbMdnsJvm()
mdns.start()

Discovered endpoints can be passed to Kadb.create(host, port) or Kadb.pair(host, port, code).

API Overview

Capability API
Connect to adbd over TCP Kadb.create(...)
USB discovery / connection Platform-specific KadbUsb.devices(...), KadbUsb.create(...)
Wireless pairing Kadb.pair(...)
Shell shell(...), openShell(), openPtyShellSession()
File transfer push(...), pull(...), openSync()
APK install install(...), installMultiple(...), uninstall(...)
Port forwarding tcpForward(...)
Transport reuse resetConnection()
Optional mDNS discovery KadbMdnsAndroid, KadbMdnsJvm

Examples

Install an APK:

Kadb.create("127.0.0.1", 5555).use { kadb ->
    kadb.install(apkFile)
}

Push a file:

Kadb.create("127.0.0.1", 5555).use { kadb ->
    kadb.push(localFile, "/data/local/tmp/remote.txt")
}

Forward a TCP port:

Kadb.create("127.0.0.1", 5555).tcpForward(
    hostPort = 7001,
    targetPort = 7001
).use {
    // localhost:7001 now forwards to the device's port 7001
}

Platform and Pairing Notes

  • Android target support starts at minSdk 23
  • Basic connect / shell / sync / install flows do not require the full adb binary
  • Pairing has stricter requirements than ordinary client operations
  • JVM pairing requires conscrypt-openjdk-uber
  • Android 6 to 8 usually need a custom Conscrypt dependency for pairing

Example JVM pairing dependency:

dependencies {
    implementation("com.flyfishxu:kadb:2.1.5")
    implementation("org.conscrypt:conscrypt-openjdk-uber:2.5.2")
}

Scope and Limitations

  • Kadb is a direct client library; transport brokering and adb server-style device tracking are out of scope.
  • USB connections are available on Android and desktop JVM. A device's USB interface must be released by other tools before Kadb can claim it.

Documentation

Acknowledgements