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?????????????????????Java??????????????????????warning??????????????????????????????????????????????????????????????????

?????????????????????add????????????????????

public void add(Object element) {
    if (!readOnly) {
        int newSize = size + 1;
        if (newSize > elements.length) {
            Object[] newElements = new Object[elements.length + 10];
            for (int i = 0; i < size; i++) {
                newElements[i] = elements[i];
            }
            elements = newElements;
        }
        elements[size++] = element;
    }
}

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public void add(Object element) {
    if (readOnly) {
        return;
    }
    if (atCapacity()) {
        grow();
    }
    addElement(element);
}
private boolean atCapacity() {
    int newSize = size + 1;
    return newSize > elements.length;
}
private void grow() {
    Object[] newElements = new Object[elements.length + 10];
    for (int i = 0; i < size; i++) {
        newElements[i] = elements[i];
    }
    elements = newElements;
}
private void addElement(Object element) {
    elements[size++] = element;
}

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??????if-else???????

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public double getIntegral() {
    if (payChannel instanceof BankChannel) {
        return paymentValue * 1.5;
    } else if (payChannel instanceof WxChannel) {
        return paymentValue * 2 - couponValue;
    } else if (payChannel instanceof AliPayChannel) {
        return paymentValue * 2 + loanValue * 1;
    }
    return 0;
}

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public abstract class IntegralStrategy {
    abstract double getIntegral(PayResult payResult);
}
public class AliPayIntegralStrategy extends IntegralStrategy {
    @Override
    double getIntegral(PayResult payResult) {
        return payResult.getPaymentValue() * 2 + payResult.getLoanValue() * 1;
    }
}
public class UnionPayIntegralStrategy extends IntegralStrategy {
    @Override
    double getIntegral(PayResult payResult) {
        return payResult.getPaymentValue() * 1.5;
    }
}
public class WxPayIntegralStrategy extends IntegralStrategy {
    @Override
    double getIntegral(PayResult payResult) {
        return payResult.getPaymentValue() * 2 - payResult.getCouponValue();
    }
}

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????????????????????????????????????????????????????PayResult???????????????????????

public static PayResult createUnionPayResult(Date payDate, Double totalValue, Double paymentValue) {
    return new PayResult(
        new BankChannel(),
        payDate,
        totalValue,
        paymentValue,
        0.0d,
        0.0d,
        new UnionPayIntegralStrategy()
    );
}
public static PayResult createWxPayResult(Date payDate, Double totalValue, Double paymentValue, Double couponValue) {
    return new PayResult(
        new WxChannel(),
        payDate,
        totalValue,
        paymentValue,
        couponValue,
        0.0d,
        new WxPayIntegralStrategy()
    );
}
public static PayResult createAliPayResult(PayChannel payChannel, Date payDate, Double totalValue, Double paymentValue, Double couponValue, Double loanValue) {
    return new PayResult(
        payChannel,
        payDate,
        totalValue,
        paymentValue,
        couponValue,
        loanValue,
        new AliPayIntegralStrategy()
    );
}
private PayResult(
    PayChannel payChannel,
    Date payDate,
    Double totalValue,
    Double paymentValue,
    Double couponValue,
    Double loanValue,
    IntegralStrategy integralStrategy
) {
    this.payChannel = payChannel;
    this.payDate = payDate;
    this.totalValue = totalValue;
    this.paymentValue = paymentValue;
    this.couponValue = couponValue;
    this.loanValue = loanValue;
    this.integralStrategy = integralStrategy;
}

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