StatePattern

StateContext.java

package com.aiming.link.purchase.model;

import com.aiming.link.purchase.AimingLinkPurchase;
import com.aiming.link.purchase.util.Purchase;
import java.util.List;

import lombok.Getter;
import lombok.Setter;

public class StateContext {
    @Getter
    @Setter
    private Statelike state;

    public StateContext () {
        state = new StateNone();
    }

    public void onBegin(AimingLinkPurchase.BuyListener listener) {
        state.onBegin(this, listener);
    }

    public void onFinished(AimingLinkPurchase.BuyListener listener, AimingLinkPurchase.BuyResult result, String details, String productId, String gameInfo, boolean isAlreadyDelivered, List<Purchase> restoreSucceededPurchases, List<Purchase> restoreFailedPurchase){
        state.onFinished(this, listener, result, details, productId, gameInfo, isAlreadyDelivered, restoreSucceededPurchases, restoreFailedPurchase);
    }
}

Statelike.java

package com.aiming.link.purchase.model;

import com.aiming.link.purchase.AimingLinkPurchase;
import com.aiming.link.purchase.util.Purchase;

import java.util.List;

interface Statelike {
    void onBegin(StateContext context, AimingLinkPurchase.BuyListener listener);
    void onFinished(StateContext context, AimingLinkPurchase.BuyListener listener, AimingLinkPurchase.BuyResult result, String details, String productId, String gameInfo, boolean isAlreadyDelivered, List<Purchase> restoreSucceededPurchases, List<Purchase> restoreFailedPurchase);
}

class StatePurchasing implements Statelike{
    @Override
    public void onBegin(StateContext context, AimingLinkPurchase.BuyListener listener) {
        if (!(context.getState() instanceof StateNone)) {
            listener.onBuyFailure(AimingLinkPurchase.BuyResult.ERROR_PROCESS_CONFLICTED, "Process conflicted");
        }
        context.setState(new StatePurchasing());
    }
//    void onBuySuccess(String productId, String gameInfo, boolean isAlreadyDelivered);
//    void onBuyFailure(BuyResult result, String details);
    @Override
    public void onFinished(StateContext context, AimingLinkPurchase.BuyListener listener, AimingLinkPurchase.BuyResult result, String details, String productId, String gameInfo, boolean isAlreadyDelivered, List<Purchase> restoreSucceededPurchases, List<Purchase> restoreFailedPurchase) {
        if (result == null) {
            // 購入成功
            listener.onBuySuccess(productId,gameInfo,isAlreadyDelivered);
        } else {
            // 購入失敗
            listener.onBuyFailure(result, details);
        }
        if (context.getState() instanceof StatePurchasing) {
            context.setState(new StateNone());
        }
    }
}

//    void onRestoreBegin();
//    void onRestoreFinished(BuyResult result, String details, List<Purchase> restoreSucceededPurchases, List<Purchase> restoreFailedPurchase);

class StateRestoring implements Statelike{
    @Override
    public void onBegin(StateContext context, AimingLinkPurchase.BuyListener listener) {
        if (!(context.getState() instanceof StateNone)) {
            listener.onRestoreFinished(AimingLinkPurchase.BuyResult.ERROR_PROCESS_CONFLICTED, "Process conflicted", null, null);
        }
        listener.onRestoreBegin();
        context.setState(new StateRestoring());
    }

    @Override
    public void onFinished(StateContext context, AimingLinkPurchase.BuyListener listener, AimingLinkPurchase.BuyResult result, String details, String productId, String gameInfo, boolean isAlreadyDelivered, List<Purchase> restoreSucceededPurchases, List<Purchase> restoreFailedPurchase) {
        listener.onRestoreFinished(result, details, restoreSucceededPurchases, restoreFailedPurchase);
        context.setState(new StateNone());
    }
}

class StateNone implements Statelike {
    @Override
    public void onBegin(StateContext context, AimingLinkPurchase.BuyListener listener) {

    }

    @Override
    public void onFinished(StateContext context, AimingLinkPurchase.BuyListener listener, AimingLinkPurchase.BuyResult result, String details, String productId, String gameInfo, boolean isAlreadyDelivered, List<Purchase> restoreSucceededPurchases, List<Purchase> restoreFailedPurchase) {

    }
}