Process: com.kronos.router, PID: 4643
    java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.kronos.router/com.kronos.sample.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.kronos.sample.MainActivity" on path: DexPathList[[zip file "/data/app/com.kronos.router-2/base.apk"],nativeLibraryDirectories=[/data/app/com.kronos.router-2/lib/x86, /system/lib, /vendor/lib]]
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2567)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
        at android.app.ActivityThread.-wrap12(ActivityThread.java)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
        at android.os.Handler.dispatchMessage(Handler.java:102)
        at android.os.Looper.loop(Looper.java:154)
        at android.app.ActivityThread.main(ActivityThread.java:6119)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
     Caused by: java.lang.ClassNotFoundException: Didn't find class "com.kronos.sample.MainActivity" on path: DexPathList[[zip file "/data/app/com.kronos.router-2/base.apk"],nativeLibraryDirectories=[/data/app/com.kronos.router-2/lib/x86, /system/lib, /vendor/lib]]
        at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:380)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
        at android.app.Instrumentation.newActivity(Instrumentation.java:1078)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2557)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726) 
        at android.app.ActivityThread.-wrap12(ActivityThread.java) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477) 
        at android.os.Handler.dispatchMessage(Handler.java:102) 
        at android.os.Looper.loop(Looper.java:154) 
        at android.app.ActivityThread.main(ActivityThread.java:6119) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) 
    	Suppressed: java.lang.NoClassDefFoundError: Failed resolution of: Landroidx/appcompat/app/AppCompatActivity;
        at java.lang.VMClassLoader.findLoadedClass(Native Method)
        at java.lang.ClassLoader.findLoadedClass(ClassLoader.java:742)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:362)

    BaseDexClassLoader
    @Override
    protected Class findClass(String name) throws ClassNotFoundException {
        Class clazz = pathList.findClass(name);
        if (clazz == null) {
            throw new ClassNotFoundException(name);
        }
        return clazz;
    }

  private final DexPathList pathList;
    /**
     * Constructs an instance.
     *
     * @param dexPath the list of jar/apk files containing classes and
     * resources, delimited by {@code File.pathSeparator}, which
     * defaults to {@code ":"} on Android
     * @param optimizedDirectory directory where optimized dex files
     * should be written; may be {@code null}
     * @param libraryPath the list of directories containing native
     * libraries, delimited by {@code File.pathSeparator}; may be
     * {@code null}
     * @param parent the parent class loader
     */
    public BaseDexClassLoader(String dexPath, File optimizedDirectory,
            String libraryPath, ClassLoader parent) {
        super(parent);
        this.originalPath = dexPath;
        this.pathList =
            new DexPathList(this, dexPath, libraryPath, optimizedDirectory);
    }

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    /**
     * Makes an array of dex/resource path elements, one per element of
     * the given array.
     */
    private static Element[] makeDexElements(ArrayList files,
            File optimizedDirectory) {
        ArrayList elements = new ArrayList();
        /*
         * Open all files and load the (direct or contained) dex files
         * up front.
         */
        for (File file : files) {
            ZipFile zip = null;
            DexFile dex = null;
            String name = file.getName();
            if (name.endsWith(DEX_SUFFIX)) {
                // Raw dex file (not inside a zip/jar).
                try {
                    dex = loadDexFile(file, optimizedDirectory);
                } catch (IOException ex) {
                    System.logE("Unable to load dex file: " + file, ex);
                }
            } else if (name.endsWith(APK_SUFFIX) || name.endsWith(JAR_SUFFIX)
                    || name.endsWith(ZIP_SUFFIX)) {
                try {
                    zip = new ZipFile(file);
                } catch (IOException ex) {
                    /*
                     * Note: ZipException (a subclass of IOException)
                     * might get thrown by the ZipFile constructor
                     * (e.g. if the file isn't actually a zip/jar
                     * file).
                     */
                    System.logE("Unable to open zip file: " + file, ex);
                }
                try {
                    dex = loadDexFile(file, optimizedDirectory);
                } catch (IOException ignored) {
                    /*
                     * IOException might get thrown "legitimately" by
                     * the DexFile constructor if the zip file turns
                     * out to be resource-only (that is, no
                     * classes.dex file in it). Safe to just ignore
                     * the exception here, and let dex == null.
                     */
                }
            } else {
                System.logW("Unknown file type for: " + file);
            }
            if ((zip != null) || (dex != null)) {
                elements.add(new Element(file, zip, dex));
            }
        }
        return elements.toArray(new Element[elements.size()]);
    }

    DexPathList
        /**
     * Finds the named class in one of the dex files pointed at by
     * this instance. This will find the one in the earliest listed
     * path element. If the class is found but has not yet been
     * defined, then this method will define it in the defining
     * context that this instance was constructed with.
     *
     * @return the named class or {@code null} if the class is not
     * found in any of the dex files
     */
    public Class findClass(String name) {
        for (Element element : dexElements) {
            DexFile dex = element.dexFile;
            if (dex != null) {
                Class clazz = dex.loadClassBinaryName(name, definingContext);
                if (clazz != null) {
                    return clazz;
                }
            }
        }
        return null;
    }
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    /**
     * Opens a DEX file from a given filename. This will usually be a ZIP/JAR
     * file with a "classes.dex" inside.
     *
     * The VM will generate the name of the corresponding file in
     * /data/dalvik-cache and open it, possibly creating or updating
     * it first if system permissions allow.  Don't pass in the name of
     * a file in /data/dalvik-cache, as the named file is expected to be
     * in its original (pre-dexopt) state.
     *
     * @param fileName
     *            the filename of the DEX file
     *
     * @throws IOException
     *             if an I/O error occurs, such as the file not being found or
     *             access rights missing for opening it
     */
    public DexFile(String fileName) throws IOException {
        mCookie = openDexFile(fileName, null, 0);
        mFileName = fileName;
        guard.open("close");
        //System.out.println("DEX FILE cookie is " + mCookie);
    }
    
     /*
     * Open a DEX file.  The value returned is a magic VM cookie.  On
     * failure, an IOException is thrown.
     */
    native private static int openDexFile(String sourceName, String outputName,
        int flags) throws IOException;

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