Conditional @Autowired based on constructor argument

Question

I'm new to spring and I'm trying to refactor some code, I have the following "Session.class":

public class Session {
    ...
    private Wallet currenetWallet;
    ...
    public Session(..., int sessionId, ...) {
        ...

        ThirdPartyToken token = context.getBean(ThirdPartyTokenDAO.class).getThirdPartyToken(sessionId);

        if (token.getExternalUser().getMerchant().getType().equals("SOAPMerchant")) {
            currenetWallet = (Wallet) context.getBean("SOAPExternalWallet", token);
        }
        else if (token.getExternalUser().getMerchant().getType().equals("JSONMerchant")) {
            currenetWallet = (Wallet) context.getBean("JSONExternalWallet", token);
        }
        else {
            currenetWallet = (Wallet) context.getBean("GuestWallet", 1000.0);
        }

        ...
    }   
}

I read that using context.getBean() is a bad practice, and makes the class untestable. What would be the correct way of wiring the currentWallet according to the above?

Inject the three values, and choose which one to use based on the merchant type — JB Nizet, Jul 11 '17 at 08:16
Today I have 3, but what if tomorrow I'll have a dozen types, wouldn't it be a waste to wire them all ? Although I do like this solution, it will be the easiest to implement — Yuval Barness, Jul 11 '17 at 08:20
You actually depend on `Wallet` class, not on `sessionId`, so this is what you should be wiring and expecting in constructor. Depending on how rest of system defined, you can have a `Wallet` prototype bean, creation of which depends on `Token`, which in turn depends on that sessionId. — M. Prokhorov, Jul 11 '17 at 08:35

score 0 · Accepted Answer · answered Jul 11 '17 at 08:16

0

Create an interface Wallet and create implementation classes like SOAPExternalWallet, JSONExternalWallet, GuestWallet.
Create a factory class and then based on the type return the right implementation from factory class.

answered Jul 11 '17 at 08:16

pvpkiran

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But then I don't use spring, I'd like the currentWallet field to be @autowired somehow... – Yuval Barness Jul 11 '17 at 08:25
1

see my answer here https://stackoverflow.com/questions/44000672/spring-how-to-change-interface-implementations-at-runtime/44001051#44001051 – pvpkiran Jul 11 '17 at 08:26

Conditional @Autowired based on constructor argument

1 Answers1