Building Cordovo Android app fails - Dex cannot parse version 52 byte code error message

Question

I an trying to build a Cordova Android app and when I try to make a build using our custom scripts which call the cordova build command I get the following error - any ideas what this could be?

Dex: Error converting bytecode to dex:
Cause: Dex cannot parse version 52 byte code.
This is caused by library dependencies that have been compiled using Java 8 or above.
If you are using the 'java' gradle plugin in a library submodule add
targetCompatibility = '1.7'
sourceCompatibility = '1.7'
to that submodule's build.gradle file.
    UNEXPECTED TOP-LEVEL EXCEPTION:
java.lang.RuntimeException: Exception parsing classes
        at com.android.dx.command.dexer.Main.processClass(Main.java:775)
        at com.android.dx.command.dexer.Main.processFileBytes(Main.java:741)
        at com.android.dx.command.dexer.Main.access$1200(Main.java:88)
        at com.android.dx.command.dexer.Main$FileBytesConsumer.processFileBytes(Main.java:1683)
        at com.android.dx.cf.direct.ClassPathOpener.processArchive(ClassPathOpener.java:284)
        at com.android.dx.cf.direct.ClassPathOpener.processOne(ClassPathOpener.java:166)
        at com.android.dx.cf.direct.ClassPathOpener.process(ClassPathOpener.java:144)
        at com.android.dx.command.dexer.Main.processOne(Main.java:695)
        at com.android.dx.command.dexer.Main.processAllFiles(Main.java:592)
        at com.android.dx.command.dexer.Main.runMultiDex(Main.java:376)
        at com.android.dx.command.dexer.Main.run(Main.java:290)
        at com.android.builder.internal.compiler.DexWrapper.run(DexWrapper.java:54)
        at com.android.builder.core.DexByteCodeConverter.lambda$dexInProcess$0(DexByteCodeConverter.java:173)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)
Caused by: com.android.dx.cf.iface.ParseException: bad class file magic (cafebabe) or version (0034.0000)
        at com.android.dx.cf.direct.DirectClassFile.parse0(DirectClassFile.java:476)
        at com.android.dx.cf.direct.DirectClassFile.parse(DirectClassFile.java:406)
        at com.android.dx.cf.direct.DirectClassFile.parseToInterfacesIfNecessary(DirectClassFile.java:388)
        at com.android.dx.cf.direct.DirectClassFile.getMagic(DirectClassFile.java:251)
        at com.android.dx.command.dexer.Main.parseClass(Main.java:787)
        at com.android.dx.command.dexer.Main.access$1600(Main.java:88)
        at com.android.dx.command.dexer.Main$ClassParserTask.call(Main.java:1722)
        at com.android.dx.command.dexer.Main.processClass(Main.java:773)
        ... 16 more

1 error; aborting

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':transformClassesWithDexForRelease'.
> com.android.build.api.transform.TransformException: java.lang.RuntimeException: java.lang.RuntimeException: com.android.ide.common.process.ProcessException: java.util.concurrent.ExecutionException: com.android.ide.common.process.ProcessException: Return code 1 for dex process

// build gradle file

apply plugin: 'com.android.application'

buildscript {
    repositories {
        mavenCentral()
        jcenter()
    }

    // Switch the Android Gradle plugin version requirement depending on the
    // installed version of Gradle. This dependency is documented at
    // http://tools.android.com/tech-docs/new-build-system/version-compatibility
    // and https://issues.apache.org/jira/browse/CB-8143
    dependencies {
        classpath 'com.android.tools.build:gradle:2.2.3'
    }
}

// Allow plugins to declare Maven dependencies via build-extras.gradle.
allprojects {
    repositories {
        mavenCentral();
        jcenter()
    }
}

task wrapper(type: Wrapper) {
    gradleVersion = '2.14.1'
}

// Configuration properties. Set these via environment variables, build-extras.gradle, or gradle.properties.
// Refer to: http://www.gradle.org/docs/current/userguide/tutorial_this_and_that.html
ext {
    apply from: 'CordovaLib/cordova.gradle'
    // The value for android.compileSdkVersion.
    if (!project.hasProperty('cdvCompileSdkVersion')) {
        cdvCompileSdkVersion = null;
    }
    // The value for android.buildToolsVersion.
    if (!project.hasProperty('cdvBuildToolsVersion')) {
        cdvBuildToolsVersion = null;
    }
    // Sets the versionCode to the given value.
    if (!project.hasProperty('cdvVersionCode')) {
        cdvVersionCode = null
    }
    // Sets the minSdkVersion to the given value.
    if (!project.hasProperty('cdvMinSdkVersion')) {
        cdvMinSdkVersion = null
    }
    // Whether to build architecture-specific APKs.
    if (!project.hasProperty('cdvBuildMultipleApks')) {
        cdvBuildMultipleApks = null
    }
    // .properties files to use for release signing.
    if (!project.hasProperty('cdvReleaseSigningPropertiesFile')) {
        cdvReleaseSigningPropertiesFile = null
    }
    // .properties files to use for debug signing.
    if (!project.hasProperty('cdvDebugSigningPropertiesFile')) {
        cdvDebugSigningPropertiesFile = null
    }
    // Set by build.js script.
    if (!project.hasProperty('cdvBuildArch')) {
        cdvBuildArch = null
    }

    // Plugin gradle extensions can append to this to have code run at the end.
    cdvPluginPostBuildExtras = []
}

// PLUGIN GRADLE EXTENSIONS START
// PLUGIN GRADLE EXTENSIONS END

def hasBuildExtras = file('build-extras.gradle').exists()
if (hasBuildExtras) {
    apply from: 'build-extras.gradle'
}

// Set property defaults after extension .gradle files.
if (ext.cdvCompileSdkVersion == null) {
    ext.cdvCompileSdkVersion = privateHelpers.getProjectTarget()
}
if (ext.cdvBuildToolsVersion == null) {
    ext.cdvBuildToolsVersion = privateHelpers.findLatestInstalledBuildTools()
}
if (ext.cdvDebugSigningPropertiesFile == null && file('debug-signing.properties').exists()) {
    ext.cdvDebugSigningPropertiesFile = 'debug-signing.properties'
}
if (ext.cdvReleaseSigningPropertiesFile == null && file('release-signing.properties').exists()) {
    ext.cdvReleaseSigningPropertiesFile = 'release-signing.properties'
}

// Cast to appropriate types.
ext.cdvBuildMultipleApks = cdvBuildMultipleApks == null ? false : cdvBuildMultipleApks.toBoolean();
ext.cdvMinSdkVersion = cdvMinSdkVersion == null ? null : Integer.parseInt('' + cdvMinSdkVersion)
ext.cdvVersionCode = cdvVersionCode == null ? null : Integer.parseInt('' + cdvVersionCode)

def computeBuildTargetName(debugBuild) {
    def ret = 'assemble'
    if (cdvBuildMultipleApks && cdvBuildArch) {
        def arch = cdvBuildArch == 'arm' ? 'armv7' : cdvBuildArch
        ret += '' + arch.toUpperCase().charAt(0) + arch.substring(1);
    }
    return ret + (debugBuild ? 'Debug' : 'Release')
}

// Make cdvBuild a task that depends on the debug/arch-sepecific task.
task cdvBuildDebug
cdvBuildDebug.dependsOn {
    return computeBuildTargetName(true)
}

task cdvBuildRelease
cdvBuildRelease.dependsOn {
    return computeBuildTargetName(false)
}

task cdvPrintProps << {
    println('cdvCompileSdkVersion=' + cdvCompileSdkVersion)
    println('cdvBuildToolsVersion=' + cdvBuildToolsVersion)
    println('cdvVersionCode=' + cdvVersionCode)
    println('cdvMinSdkVersion=' + cdvMinSdkVersion)
    println('cdvBuildMultipleApks=' + cdvBuildMultipleApks)
    println('cdvReleaseSigningPropertiesFile=' + cdvReleaseSigningPropertiesFile)
    println('cdvDebugSigningPropertiesFile=' + cdvDebugSigningPropertiesFile)
    println('cdvBuildArch=' + cdvBuildArch)
    println('computedVersionCode=' + android.defaultConfig.versionCode)
    android.productFlavors.each { flavor ->
        println('computed' + flavor.name.capitalize() + 'VersionCode=' + flavor.versionCode)
    }
}

android {
    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = ['src']
            resources.srcDirs = ['src']
            aidl.srcDirs = ['src']
            renderscript.srcDirs = ['src']
            res.srcDirs = ['res']
            assets.srcDirs = ['assets']
            jniLibs.srcDirs = ['libs']
        }
    }

    defaultConfig {
        versionCode cdvVersionCode ?: new BigInteger("" + privateHelpers.extractIntFromManifest("versionCode"))
        applicationId privateHelpers.extractStringFromManifest("package")

        minSdkVersion 21
        targetSdkVersion 26
        multiDexEnabled true

        if (cdvMinSdkVersion != null) {
            minSdkVersion cdvMinSdkVersion
        }
    }

    lintOptions {
      abortOnError false;
    }

    compileSdkVersion cdvCompileSdkVersion
    buildToolsVersion cdvBuildToolsVersion

    if (Boolean.valueOf(cdvBuildMultipleApks)) {
        productFlavors {
            armv7 {
                versionCode defaultConfig.versionCode*10 + 2
                ndk {
                    abiFilters "armeabi-v7a", ""
                }
            }
            x86 {
                versionCode defaultConfig.versionCode*10 + 4
                ndk {
                    abiFilters "x86", ""
                }
            }
            all {
                ndk {
                    abiFilters "all", ""
                }
            }
        }
    }
    /*

    ELSE NOTHING! DON'T MESS WITH THE VERSION CODE IF YOU DON'T HAVE TO!

    else if (!cdvVersionCode) {
      def minSdkVersion = cdvMinSdkVersion ?: privateHelpers.extractIntFromManifest("minSdkVersion")
      // Vary versionCode by the two most common API levels:
      // 14 is ICS, which is the lowest API level for many apps.
      // 20 is Lollipop, which is the lowest API level for the updatable system webview.
      if (minSdkVersion >= 20) {
        defaultConfig.versionCode += 9
      } else if (minSdkVersion >= 14) {
        defaultConfig.versionCode += 8
      }
    }
    */

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_6
        targetCompatibility JavaVersion.VERSION_1_6
    }

    if (cdvReleaseSigningPropertiesFile) {
        signingConfigs {
            release {
                // These must be set or Gradle will complain (even if they are overridden).
                keyAlias = ""
                keyPassword = "__unset" // And these must be set to non-empty in order to have the signing step added to the task graph.
                storeFile = null
                storePassword = "__unset"
            }
        }
        buildTypes {
            release {
                signingConfig signingConfigs.release
            }
        }
        addSigningProps(cdvReleaseSigningPropertiesFile, signingConfigs.release)
    }
    if (cdvDebugSigningPropertiesFile) {
        addSigningProps(cdvDebugSigningPropertiesFile, signingConfigs.debug)
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: '*.jar')
    // SUB-PROJECT DEPENDENCIES START
    debugCompile(project(path: "CordovaLib", configuration: "debug"))
    releaseCompile(project(path: "CordovaLib", configuration: "release"))
    compile "net.gotev:uploadservice:3.2.3"
    compile "net.gotev:uploadservice-okhttp:3.2.3"
    compile "com.sromku:simple-storage:1.2.0"
    compile "com.android.support:support-v4:24.1.1+"
    // SUB-PROJECT DEPENDENCIES END
}

def promptForReleaseKeyPassword() {
    if (!cdvReleaseSigningPropertiesFile) {
        return;
    }
    if ('__unset'.equals(android.signingConfigs.release.storePassword)) {
        android.signingConfigs.release.storePassword = privateHelpers.promptForPassword('Enter key store password: ')
    }
    if ('__unset'.equals(android.signingConfigs.release.keyPassword)) {
        android.signingConfigs.release.keyPassword = privateHelpers.promptForPassword('Enter key password: ');
    }
}

gradle.taskGraph.whenReady { taskGraph ->
    taskGraph.getAllTasks().each() { task ->
        if (task.name == 'validateReleaseSigning' || task.name == 'validateSigningRelease') {
            promptForReleaseKeyPassword()
        }
    }
}

def addSigningProps(propsFilePath, signingConfig) {
    def propsFile = file(propsFilePath)
    def props = new Properties()
    propsFile.withReader { reader ->
        props.load(reader)
    }

    def storeFile = new File(props.get('key.store') ?: privateHelpers.ensureValueExists(propsFilePath, props, 'storeFile'))
    if (!storeFile.isAbsolute()) {
        storeFile = RelativePath.parse(true, storeFile.toString()).getFile(propsFile.getParentFile())
    }
    if (!storeFile.exists()) {
        throw new FileNotFoundException('Keystore file does not exist: ' + storeFile.getAbsolutePath())
    }
    signingConfig.keyAlias = props.get('key.alias') ?: privateHelpers.ensureValueExists(propsFilePath, props, 'keyAlias')
    signingConfig.keyPassword = props.get('keyPassword', props.get('key.alias.password', signingConfig.keyPassword))
    signingConfig.storeFile = storeFile
    signingConfig.storePassword = props.get('storePassword', props.get('key.store.password', signingConfig.storePassword))
    def storeType = props.get('storeType', props.get('key.store.type', ''))
    if (!storeType) {
        def filename = storeFile.getName().toLowerCase();
        if (filename.endsWith('.p12') || filename.endsWith('.pfx')) {
            storeType = 'pkcs12'
        } else {
            storeType = signingConfig.storeType // "jks"
        }
    }
    signingConfig.storeType = storeType
}

for (def func : cdvPluginPostBuildExtras) {
    func()
}

// This can be defined within build-extras.gradle as:
//     ext.postBuildExtras = { ... code here ... }
if (hasProperty('postBuildExtras')) {
    postBuildExtras()
}

I am using the following on Windows 10 Pro :-

javac -version
javac 1.8.0_221

javaw -version
java version "1.8.0_221"
Java(TM) SE Runtime Environment (build 1.8.0_221-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.221-b11, mixed mode)

NodeJS : v10.13.0
npm    : 6.7.0

Gradle is the latest version as of 02/09/2019 which is gradle-5.6.1

Answer 1

It reads:

ParseException: bad class file magic (cafebabe) or version (0034.0000)

0x0034 is version 52 byte code, which means the some class had been compiled with JDK 8, which is not being understood by that version of dex. It even explicitly demands the source/target compatibility mode:

Dex: Error converting bytecode to dex:
Cause: Dex cannot parse version 52 byte code.

This is caused by library dependencies that have been compiled using Java 8 or above.

If you are using the 'java' gradle plugin in a library submodule add
targetCompatibility = '1.7'
sourceCompatibility = '1.7'
to that submodule's build.gradle file.

So there are two options:

a) either follow the advice and edit the compileOptions (this not only applies to the java plugin):

android {
    compileOptions {
        // sourceCompatibility JavaVersion.VERSION_1_6
        // targetCompatibility JavaVersion.VERSION_1_6
        sourceCompatibility JavaVersion.VERSION_1_7
        targetCompatibility JavaVersion.VERSION_1_7
    }
}

---

b) build with JDK 8.

You are actually building with rather old versions:

dependencies {
    classpath "com.android.tools.build:gradle:2.2.3"
}

task wrapper(type: Wrapper) {
    gradleVersion = "2.14.1"
}

while the current versions are:

dependencies {
    classpath "com.android.tools.build:gradle:3.5.0"
}

task wrapper(type: Wrapper) {
    gradleVersion = "5.4.1"
}

When I read version 2.2.3 I'd assume a version of Android Studio just as old. Update to Android Studio 3.5.0 and have an embedded JRE 8 installed with it. That Android Studio might still have an embedded JRE 7 (no matter what the JDK on path claims to be, because the global JDK and the embedded JRE are two different installations). The same goes for Gradle, because it might use the local wrapper at version 2.14.1 instead of the global installation at version 5.6.1. One can tell Gradle to use a specific JDK with org.gradle.java.home, but the IDE might in general be too old. You'd need at least Android Studio 3.0.0 for Java 8 support.