How can I detect the Android runtime (Dalvik or ART)?

Question

Google added a new ART runtime with Android 4.4. How can I determine whether ART or Dalvik is the current runtime?

Answer 1

For anyone needing a JNI version:

#include 

static bool isArtEnabled() {
    char buf[PROP_VALUE_MAX] = {};
    __system_property_get("persist.sys.dalvik.vm.lib.2", buf);
    // This allows libartd.so to be detected as well.
    return strncmp("libart", buf, 6) == 0;
}

Or if you want to follow a code path closer to what shoe rat posted,

static bool isArtEnabled(JNIEnv *env)
{
    // Per https://developer.android.com/guide/practices/verifying-apps-art.html
    // if the result of System.getProperty("java.vm.version") starts with 2,
    // ART is enabled.

    jclass systemClass = env->FindClass("java/lang/System");

    if (systemClass == NULL) {
        LOGD("Could not find java.lang.System.");
        return false;
    }

    jmethodID getProperty = env->GetStaticMethodID(systemClass,
        "getProperty", "(Ljava/lang/String;)Ljava/lang/String;");

    if (getProperty == NULL) {
        LOGD("Could not find java.lang.System.getProperty(String).");
        return false;
    }

    jstring propertyName = env->NewStringUTF("java.vm.version");

    jstring jversion = (jstring)env->CallStaticObjectMethod(
        systemClass, getProperty, propertyName);

    if (jversion == NULL) {
        LOGD("java.lang.System.getProperty('java.vm.version') did not return a value.");
        return false;
    }

    const char *version = env->GetStringUTFChars(jversion, JNI_FALSE);

    // Lets flip that check around to better bullet proof us.
    // Consider any version which starts with "1." to be Dalvik,
    // and all others to be ART.
    bool isArtEnabled = !(strlen(version) < 2 ||
        strncmp("1.", version, 2) == 0);

    LOGD("Is ART enabled? %d (%s)", isArtEnabled, version);

    env->ReleaseStringUTFChars(jversion, version);

    return isArtEnabled;
}