Attempt to invoke virtual method 'java.security.PrivateKey java.security.KeyPair.getPrivate()' on a null object reference

[rossholdway]

Expected behavior

Null object reference should be handled.

Actual behavior

App (sometimes) crashes with java.lang.NullPointerException.

Steps to reproduce the problem

Seen on Android 13 to 11 (so far)

Specifications like the version of the library, operating system etc.

Release com.microsoft.aad:adal:4.7.1

Relevant logs and traces

Exception java.lang.NullPointerException: Attempt to invoke virtual method 'java.security.PrivateKey java.security.KeyPair.getPrivate()' on a null object reference
  at com.microsoft.aad.adal.StorageHelper.unwrap (StorageHelper.java:673)
  at com.microsoft.aad.adal.StorageHelper.getUnwrappedSecretKey (StorageHelper.java:622)
  at com.microsoft.aad.adal.StorageHelper.getKey (StorageHelper.java:406)
  at com.microsoft.aad.adal.StorageHelper.decrypt (StorageHelper.java:276)
  at com.microsoft.aad.adal.DefaultTokenCacheStore.decrypt (DefaultTokenCacheStore.java:152)
  at com.microsoft.aad.adal.DefaultTokenCacheStore.getItem (DefaultTokenCacheStore.java:170)
  at com.microsoft.aad.adal.DelegatingCache.getItem (DelegatingCache.java:64)
  at com.microsoft.aad.adal.TokenCacheAccessor.getRegularRefreshTokenCacheItem (TokenCacheAccessor.java:181)
  at com.microsoft.aad.adal.TokenCacheAccessor.getATFromCache (TokenCacheAccessor.java:144)
  at com.microsoft.aad.adal.AcquireTokenSilentHandler.getAccessToken (AcquireTokenSilentHandler.java:110)
  at com.microsoft.aad.adal.AcquireTokenRequest.tryAcquireTokenSilentLocally (AcquireTokenRequest.java:587)
  at com.microsoft.aad.adal.AcquireTokenRequest.acquireTokenSilentFlow (AcquireTokenRequest.java:552)
  at com.microsoft.aad.adal.AcquireTokenRequest.tryAcquireTokenSilent (AcquireTokenRequest.java:445)
  at com.microsoft.aad.adal.AcquireTokenRequest.performAcquireTokenRequest (AcquireTokenRequest.java:424)
  at com.microsoft.aad.adal.AcquireTokenRequest.access$200 (AcquireTokenRequest.java:63)
  at com.microsoft.aad.adal.AcquireTokenRequest$1.run (AcquireTokenRequest.java:137)
  at java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1137)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:637)
  at java.lang.Thread.run (Thread.java:1012)

[rossholdway]

This is caused by Android deleting the "AdalKey" alias, which can happen after a device is restored from cloud backup. If the alias is missing you can clear the cache to restore functionality.