Migration from 2.2.x to 2.3.0

This guide explains how to migrate projects using Wultra Mobile Token SDK for Android from 2.2.x to 2.3.x.

The key change is a move from ThreeTenABP (org.threeten.bp) to the platform java.time API. ThreeTenABP has been discontinued, so we aligned the SDK with the modern, supported APIs.

Because we continue to support minSdk 21, core library desugaring is required in your app.

1) Why this change?

• ThreeTenABP is discontinued and requires manual Application initialization that’s easy to miss.
• java.time is the standard Java 8+ time API and is built into Android API 26+. With core library desugaring, it also works on API 21–25.

2) What changed in the SDK

2.1 Time types moved to java.time

• All public date/time types now use java.time (e.g., ZonedDateTime, Instant, ZoneId).

2.2 New helper: synchronized timestamp for ProximityCheck

You can now use the static factory ProximityCheck.withSynchronizedTime to create a ProximityCheck instance with a timestamp that prefers server-synchronized time from PowerAuth, falling back to the device clock if synchronization is not available.

2.3 Initialization

• No more ThreeTenABP initialization in your Application. Remove any AndroidThreeTen.init(context) or similar calls.

3) App changes you must do

Because this SDK now uses java.time while supporting minSdk 21, you must enable core library desugaring to compile and run.

Gradle (kts)

app/build.gradle.kts

android {
    compileOptions {
        // Enable desugaring of core library APIs (java.time, streams, etc.)
        isCoreLibraryDesugaringEnabled = true
    }
}

dependencies {
    // AGP 7.4+ supports desugar_jdk_libs:2.x
    coreLibraryDesugaring("com.android.tools:desugar_jdk_libs:2.1.5")
}

Replace imports

Search & replace in your codebase:

Most APIs are 1:1 compatible:

// ThreeTenABP
val zdt = org.threeten.bp.ZonedDateTime.now()

// java.time
val zdt = java.time.ZonedDateTime.now()

Remove ThreeTenABP init

Delete any AndroidThreeTen.init(appContext) or similar in Application.

4) Summary

• ThreeTenABP is discontinued → we switched to java.time.
• Prefer ProximityCheck.withSynchronizedTime(...) to reduce clock‑drift issues in time‑sensitive flows.
• Remove ThreeTenABP initialization and imports.
• Most API usage remains the same; update imports and any custom adapters you maintain.