Desugaring - Java 8 Stream API with Proguard crash in release version

Question

The app crashes only in its release version with desugaring Java 8 for Android.

compileOptions {
        // Flag to enable support for the new language APIs
        coreLibraryDesugaringEnabled true
        // Sets Java compatibility to Java 8
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }


coreLibraryDesugaring 'com.android.tools:desugar_jdk_libs:1.1.5'

This is what we tried but did not work.

-keep class java.util.stream.** { *; }

The sample code is just using filter

List<MovieModel> = someList.stream().filter(it -> !it.getImdbId().equalsIgnoreCase(model.getImdbId())).collect(Collectors.toList())

Error:

java.lang.ClassCastException: j$.util.stream.p cannot be cast to j$.wrappers.p

Answer 1

coreLibraryDesugaring 'com.android.tools:desugar_jdk_libs:1.2.2'

tools:desugar_jdk_libs should upgrade to 1.1.5 or heigher.

https://developer.android.com/studio/write/java8-support.html