I am using Java 8 in my Android project. I have setup both Jack (In android application module) and Retrolambda (in other modules).
The problem I am having is that my Lambda expressions crash in one specific scenario when I try to make it use class variable (and I can reproduce it in any module), in all others situations it works as expected. Maybe this is a standard Java behaviour, but I couldn't find any explanations so far. Would anyone know where the problem is? My class and crash below:
public class LambdaBugTest {
private final String parentClassVariableString = "parentClassVariableString";
public void testLambdas() {
// ----------- THESE WORK OK --------------
final Functional simpleLambdaWorks = text -> System.out.print(text);
final Functional methodReferenceWorks = System.out::print;
final Functional interfaceWithClassParamWorks = new Functional() {
@Override
public void doSomething(String text) {
System.out.print(text + " " + parentClassVariableString);
}
};
// -----------------------------------------
// ----------- THIS ONE CRASHES ------------
final Functional lambdaWithClassParamCrashes = text -> System.out.print(text + " " + parentClassVariableString);
// -----------------------------------------
simpleLambdaWorks.doSomething("Text from simpleLambdaWorks");
methodReferenceWorks.doSomething("Text from methodReferenceWorks");
interfaceWithClassParamWorks.doSomething("Text from interfaceWithClassParamWorks");
lambdaWithClassParamCrashes.doSomething("Text from lambdaWithClassParamCrashes");
}
private interface Functional {
void doSomething(String text);
}
}
The crash log:
08-21 00:27:41.564 25752-25752/debug E/AndroidRuntime: FATAL EXCEPTION: main
Process: debug, PID: 25752
java.lang.IncompatibleClassChangeError: The method 'void data.api.mapper.LambdaBugTest.data_api_mapper_LambdaBugTest_lambda$testLambdas$1(java.lang.String)' was expected to be of type direct but instead was found to be of type virtual (declaration of 'java.lang.reflect.ArtMethod' appears in /system/framework/core-libart.jar)
at data.api.mapper.LambdaBugTest.access$lambda$1(LambdaBugTest.java)
at data.api.mapper.LambdaBugTest$$Lambda$5.doSomething(Unknown)
at data.api.mapper.LambdaBugTest.testLambdas(LambdaBugTest.java:27)
at home.presentation.HomeActivity.onCreate(HomeActivity.java:47)
at android.app.Activity.performCreate(Activity.java:5990)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2278)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Google are no longer supporting android-jack.
Jack is no longer supported, and you should first disable Jack to use the Java 8 support built into the default toolchain
Android Studio 3.0 and later supports Lambdas expressions. Configure build.gradle file:
android {
...
// Configure only for each module that uses Java 8
// language features (either in its source code or
// through dependencies).
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
}
Note: If Android Studio detects that your project is using Jack, Retrolambda, or DexGuard, the IDE uses Java 8 support provided by those tools instead. However, consider migrating to the default toolchain
来源:https://stackoverflow.com/questions/39059551/lambda-expressions-crash-with-incompatibleclasschangeerror-in-android-when-using