exception appears during reinitializing Preferences

[balamyt]

in build.gradle:
implementation 'com.github.iamironz:binaryprefs:0.9.9'

сreate the settings as follows

return new BinaryPreferencesBuilder(MainApplication.getInstance())
            .name(BuildConfig.PREFERENCE_FOLDER)
            .encryption(customEncryptor)
            .registerPersistable(MyEntity.KEY, MyEntity.class)
            .build();//crash is here

entity class

public final class MyEntity implements Persistable, Parcelable {

   private int mId;
   private String mSource;
   private long mLastModification;
   private int mRating;


   public MyEntity(int id, String source, long lastModification, int rating) {
      mId = id;
      mSource = source;
      mLastModification = lastModification;
      mRating = rating;
   }

   //...

   @Override
   public void writeExternal(DataOutput out) {
      out.writeInt(mId);
      out.writeString(mSource);
      out.writeLong(mLastModification);
      out.writeInt(mRating);
   }

   @Override
   public void readExternal(DataInput in) {
      mId = in.readInt();
      mSource = in.readString();
      mLastModification = in.readLong();
      mRating = in.readInt();
   }

   @Override
   public Persistable deepClone() {
      return new MyEntity(mId, mSource, mLastModification, mRating);
   }

   //...
}

When first created Preference it's all right. But if called

mPreferences.edit().putPersistable(key, myEntityInstance).commit();

and then app is killed and removed from recents screen then during the next initialization appears exception:

com.ironz.binaryprefs.exception.FileOperationException: java.util.concurrent.ExecutionException: java.lang.ArrayIndexOutOfBoundsException: length=0; index=0
at com.ironz.binaryprefs.task.Completable.completeBlockingUnsafe(Completable.java:44)
at com.ironz.binaryprefs.BinaryPreferences.fetchCache(BinaryPreferences.java:64)
at com.ironz.binaryprefs.BinaryPreferences.(BinaryPreferences.java:43)
at com.ironz.binaryprefs.BinaryPreferencesBuilder.build(BinaryPreferencesBuilder.java:88)
at by.klepcha.app.dagger.ActivityModule.providePreferences(ActivityModule.java:53)
...
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703)
Caused by: java.util.concurrent.ExecutionException: java.lang.ArrayIndexOutOfBoundsException: length=0; index=0
at java.util.concurrent.FutureTask.report(FutureTask.java:93)
at java.util.concurrent.FutureTask.get(FutureTask.java:163)
at com.ironz.binaryprefs.task.Completable.completeBlockingUnsafe(Completable.java:42)
at com.ironz.binaryprefs.BinaryPreferences.fetchCache(BinaryPreferences.java:64) 
at com.ironz.binaryprefs.BinaryPreferences.(BinaryPreferences.java:43) 
at com.ironz.binaryprefs.BinaryPreferencesBuilder.build(BinaryPreferencesBuilder.java:88) 
at by.klepcha.app.dagger.ActivityModule.providePreferences(ActivityModule.java:53) 
...
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703) 
Caused by: java.lang.ArrayIndexOutOfBoundsException: length=0; index=0
at com.ironz.binaryprefs.serialization.SerializerFactory.deserialize(SerializerFactory.java:54)
at com.ironz.binaryprefs.BinaryPreferences$1.run(BinaryPreferences.java:59)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:422)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:818)

[iamironz]

Hi.
Thanks for issue submitting.
I will investigate this as soon as possible.

Regards.

[iamironz]

@balamyt I see that you has no have default constructor for MyEntity class. You actually don't?

[iamironz]

Also your customEncryptor#encrypt or recrypt field's methods implementation returns correct encrypted result or byte[0] ?

[iamironz]

This usually happens if you provide empty byte array into FileAdapter for saving.

[iamironz]

Also try to use no-op encryption to replay the situation: https://github.com/iamironz/binaryprefs/blob/master/library/src/main/java/com/ironz/binaryprefs/encryption/ByteEncryption.java#L27-L37

[balamyt]

I see that you has no have default constructor for MyEntity class. You actually don't?
Yes, I have not default constructor.

my customEncryptor#encrypt:

   @Override
   public byte[] encrypt(byte[] bytes) {
      if (!hasAlias()) {
         throw createExceptionForDevelopment("set aliases to keystore before encrypt");
      }

      try {
         KeyStore.PrivateKeyEntry privateKeyEntry = (KeyStore.PrivateKeyEntry) mKeyStore.getEntry(mAlias, null);
         RSAPublicKey publicKey = (RSAPublicKey) privateKeyEntry.getCertificate().getPublicKey();

         Cipher inCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding", "AndroidOpenSSL");
         inCipher.init(Cipher.ENCRYPT_MODE, publicKey);

         return encrypt(bytes, inCipher);

      } catch (NoSuchAlgorithmException | UnrecoverableEntryException | KeyStoreException | NoSuchProviderException e) {
         throw createExceptionForUser("in encrypt() something wrong at process with encryption", e, e.getLocalizedMessage());
      } catch (NoSuchPaddingException | InvalidKeyException e) {
         throw createExceptionForDevelopment("need check to correct alias before");
      }
   }

   private byte[] encrypt(byte[] bytes, Cipher inCipher) throws AppKeystoreException {
      ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
      CipherOutputStream cipherOutputStream = new CipherOutputStream(outputStream, inCipher);
      try {
         cipherOutputStream.write(bytes);
         return outputStream.toByteArray();
      } catch (IOException e) {
         throw createExceptionForUser("in encrypt() something wrong at process with cipherOutputStream", e, e.getLocalizedMessage());
      } finally {
         CloseableUtils.close(cipherOutputStream);
      }
   }

[iamironz]

@balamyt try create an unit test which encrypts and decrypts non-empty byte[] value with your encryption.

[iamironz]

Also please note that you should have default constructor because during initialization it will be called.

[balamyt]

Thank!!
It's all right!
The problem was my encryption implementation.

[iamironz]

Also i've added two stages byte array length checking:

iamironz@bf0ef9d
iamironz@53678f7

This checks will be in 1.0.0-ALPHA1 release.

Regards.