Sending bitcoins from one wallet to another

Bitcoinj library is a Java implementation of the Bitcoin protocol. It can maintain a wallet, send/receive transactions.in order to perform transaction there are certian steps that need to be followed .Consider the below written program which depict a simple bitcoin transaction.

public class SendCoin {

   public static void main(String[] args) {
           File file = new File("/opt/wallet.dat");
           NetworkParameters params=TestNet3Params.get();
           try
           {
               Wallet wallet=Wallet.loadFromFile(file);
               BlockStore block=new MemoryBlockStore(params);
               BlockChain chain=new BlockChain(params,block);
               chain.addWallet(wallet);
               PeerGroup peer=new PeerGroup(params,chain);
               peer.addAddress(new PeerAddress(InetAddress.getByName("127.0.0.1"),18333));

               peer.startAsync();
               peer.downloadBlockChain();
               Coin btcCoin = Coin.parseCoin("0.0001");
               Address receiverAddress=new Address(params, "mzD8ncNmbgBdrfJF5RfXkPAStKZS9TLMvj");

Wallet.SendRequest.DEFAULT_FEE_PER_KB = Coin.ZERO;

               SendRequest request = SendRequest.to(receiverAddress, btcCoin);
               request.ensureMinRequiredFee = false;
               request.fee = Coin.valueOf(10000);
               request.feePerKb = Coin.ZERO;
               Transaction transaction = wallet.sendCoins(request);
               wallet.completeTx(request);

               wallet.commitTx(request.tx);

               TransactionBroadcast future = peer.broadcastTransaction(request.tx);
               future.broadcast();
               String transactionHash = request.tx.getHashAsString();
               System.out.println("transaction hash"+transactionHash)
           }
           catch(Exception ex)
           {
               ex.printStackTrace();
           }