使用Java状态机可以很好地管理流量卡的生命周期状态，以下是一个简单的示例代码：

首先，我们需要定义枚举类型来表示卡片的不同状态：

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public enum CardState {
    NOT_ACTIVATED, // 未开卡
    ACTIVATED, // 已开卡
    EXPIRED, // 过期
    CANCELED // 注销
}

然后，我们需要定义状态机的转换规则，即从一个状态转换到另一个状态的条件和操作。我们可以使用一个Map来表示状态转换规则，其中键是当前状态，值是下一个状态和需要执行的操作。

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public class CardStateMachine {
    private Map<CardState, Map<CardState, Runnable>> stateTransitions;

    public CardStateMachine() {
        stateTransitions = new HashMap<>();

        // 未开卡 -> 已开卡
        Map<CardState, Runnable> notActivatedTransitions = new HashMap<>();
        notActivatedTransitions.put(CardState.ACTIVATED, () -> System.out.println("卡片已开卡"));
        stateTransitions.put(CardState.NOT_ACTIVATED, notActivatedTransitions);

        // 已开卡 -> 过期
        Map<CardState, Runnable> activatedTransitions = new HashMap<>();
        activatedTransitions.put(CardState.EXPIRED, () -> System.out.println("卡片已过期"));
        stateTransitions.put(CardState.ACTIVATED, activatedTransitions);

        // 过期 -> 注销
        Map<CardState, Runnable> expiredTransitions = new HashMap<>();
        expiredTransitions.put(CardState.CANCELED, () -> System.out.println("卡片已注销"));
        stateTransitions.put(CardState.EXPIRED, expiredTransitions);

        // 已开卡 -> 注销
        Map<CardState, Runnable> canceledTransitions = new HashMap<>();
        canceledTransitions.put(CardState.CANCELED, () -> System.out.println("卡片已注销"));
        stateTransitions.put(CardState.ACTIVATED, canceledTransitions);
    }

    public void transition(CardState currentState, CardState nextState) {
        if (stateTransitions.containsKey(currentState) && stateTransitions.get(currentState).containsKey(nextState)) {
            Runnable action = stateTransitions.get(currentState).get(nextState);
            action.run();
        } else {
            throw new IllegalStateException("Invalid state transition");
        }
    }
}

最后，我们可以使用状态机来管理流量卡的生命周期状态：

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public class Main {
    public static void main(String[] args) {
        CardStateMachine stateMachine = new CardStateMachine();

        CardState currentState = CardState.NOT_ACTIVATED;

        // 开卡
        stateMachine.transition(currentState, CardState.ACTIVATED);
        currentState = CardState.ACTIVATED;

        // 过期
        stateMachine.transition(currentState, CardState.EXPIRED);
        currentState = CardState.EXPIRED;

        // 注销
        stateMachine.transition(currentState, CardState.CANCELED);
    }
}

当我们运行上面的代码时，输出应该如下：

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卡片已开卡
卡片已过期
卡片已注销