如何在 Gradle 中为 Kotlin 项目正确设置 java 版本？ （由于收到“No virtual method”错误，我无法访问函数）

Question

    @RequiresApi(Build.VERSION_CODES.TIRAMISU)
    fun startStreaming(setImage: (ByteArray) -> Unit) {
        scope.launch {
            while (true) {
                try {
                    // screenStream is an object of DataInputStream class
                    val jpegImageByteArray = screenStream!!.readAllBytes() //---error-here
                    withContext(Dispatchers.Main) { setImage(jpegImageByteArray) }
                } catch (e: Exception) {
                    e.printStackTrace()
                }
                Thread.sleep(1000)
            }
        }
    }

Error -

FATAL EXCEPTION: DefaultDispatcher-worker-1
Process: com.example.g_stream, PID: 19524
java.lang.NoSuchMethodError: No virtual method readAllBytes()[B in class Ljava/io/DataInputStream; or its super classes (declaration of 'java.io.DataInputStream' appears in /system/framework/core-oj.jar)
    at com.example.g_stream.viewmodel.StreamViewModel$startStreaming$1.invokeSuspend(StreamViewModel.kt:119)
    at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
    at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
    at kotlinx.coroutines.internal.LimitedDispatcher.run(LimitedDispatcher.kt:42)
    at kotlinx.coroutines.scheduling.TaskImpl.run(Tasks.kt:95)
    at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:570)
    at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:749)
    at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:677)
    at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:664)
    Suppressed: kotlinx.coroutines.DiagnosticCoroutineContextException: [StandaloneCoroutine{Cancelling}@a113203, Dispatchers.IO]

After some searches I concluded that the reason is because the code is being compiled to a lower java version. So, I tried fixing that but, it didn't change anything. here's the gradle script -

plugins {
    id 'com.android.application'
    id 'org.jetbrains.kotlin.android'
    id 'androidx.navigation.safeargs.kotlin'
}

android {
    compileSdk 33

    defaultConfig {
        applicationId "com.example.g_stream"
        minSdk 26
        targetSdk 33
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_12 //---see-here
        targetCompatibility JavaVersion.VERSION_12 //---see-here
    }
    kotlinOptions {
        jvmTarget = '11' //---see-here
    }
    buildFeatures {
        viewBinding true
        dataBinding true
    }
    namespace 'com.example.g_stream'
}

dependencies {
    implementation 'androidx.core:core-ktx:1.9.0'
    implementation 'androidx.appcompat:appcompat:1.5.1'
    implementation 'com.google.android.material:material:1.6.1' // do not update, keep 1.6.1
    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'

    //------------------------------------------------------------------------------------navigation
    def nav_version = "2.5.3"
    implementation "androidx.navigation:navigation-fragment-ktx:$nav_version"
    implementation "androidx.navigation:navigation-ui-ktx:$nav_version"

    //--------------------------------------------------------------------------------------espresso
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.5'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'

    //---------------------------------------------------------------------------------------barcode
    implementation 'com.google.mlkit:barcode-scanning:17.0.3'

    //---------------------------------------------------------------------------------------CameraX
    def camerax_version = "1.3.0-alpha02"
    implementation "androidx.camera:camera-camera2:$camerax_version"
    implementation "androidx.camera:camera-lifecycle:$camerax_version"
    implementation "androidx.camera:camera-view:$camerax_version"

    //------------------------------------------------------------------------------------------Gson
    implementation 'com.google.code.gson:gson:2.10'

    //--------------------------------------------------------------------------------------joystick
    implementation 'io.github.controlwear:virtualjoystick:1.10.1'
}

Another post said this might be because this is a purely Kotlin project. So I tried setting the jvmTarget to 11. even that didn't help.

What am I missing here?

Answer 1

OP here. @RequiresApi(Build.VERSION_CODES.TIRAMISU) is probably the culprit here. The android device I was using didn't meet the spec. the readAllBytes function requires API 33. So naturally, since my device wasn't API level 33, the function wasn't found and hence, the error. And yes, my assumptions of this issue being a gradle problem was wrong.