question: private void cleanMapping ( ) { ArrayList < Integer > toRemove = new ArrayList < Integer > ( ) ; int size = mListMapping . size ( ) ; for ( int i = 0 ; i < size ; ++ i ) { if ( mListMapping . keyAt ( i ) == mListMapping . valueAt ( i ) ) { toRemove . add ( mListMapping . keyAt ( i ) ) ; } } size = toRemove . size ( ) ; for ( int i = 0 ; i < size ; ++ i ) { mListMapping . delete ( toRemove . get ( i ) ) ; } }
target:  Remove unnecessary mappings from sparse array.