Hands-On High Performance with Spring 5

Code scattering

Code scattering means crosscutting concerns are duplicated across all modules of an application. Let's look at the following example to understand code scattering:

public class TransferServiceImpl implements TransferService {  public void transfer(Account source, Account dest, Double amount) {    //permission check    if (!hasPermission(user) {      throw new AuthorizationException();    }  }}public class AccountServiceImpl implements AccountService {  public void withdraw(Account userAccount, Double amount) {    //Permission check    if (!hasPermission(user) {      throw new AuthorizationException();    }}

As we saw in preceding code sample, the permission check (security) is our crosscutting concern that is duplicated in all services.

These code tangling ...