question: public boolean onOwnerChanged ( GridCacheEntryEx entry , GridCacheMvccCandidate owner ) { if ( owner != null ) { IgniteTxAdapter tx = tx ( owner . version ( ) ) ; if ( tx == null ) tx = nearTx ( owner . version ( ) ) ; if ( tx != null ) { if ( ! tx . local ( ) ) { if ( log . isDebugEnabled ( ) ) log . debug ( "Found transaction for owner changed event [owner=" + owner + ", entry=" + entry + ", tx=" + tx + ']' ) ; tx . onOwnerChanged ( entry , owner ) ; return true ; } else if ( log . isDebugEnabled ( ) ) log . debug ( "Ignoring local transaction for owner change event: " + tx ) ; } else if ( log . isDebugEnabled ( ) ) log . debug ( "Transaction not found for owner changed event [owner=" + owner + ", entry=" + entry + ']' ) ; } return false ; }
target:  Callback invoked whenever a member of a transaction acquires lock ownership.