question: public boolean isUserExists ( String userID ) throws DataStoreProviderException { if ( userID == null ) { throw new DataStoreProviderException ( bundle . getString ( "nullUserId" ) ) ; } try { SSOToken adminToken = AccessController . doPrivileged ( AdminTokenAction . getInstance ( ) ) ; AMIdentity amId = IdUtils . getIdentity ( adminToken , userID ) ; return amId . isActive ( ) ; } catch ( IdRepoException ide ) { debug . message ( "IdRepoDataStoreProvider.isUserExists()" , ide ) ; return false ; } catch ( SSOException ssoe ) { debug . error ( "IdRepoDataStoreProvider.isUserExists() : SSOException" , ssoe ) ; throw new DataStoreProviderException ( ssoe ) ; } }
target:  Checks if a given user exists.