java - 多线程、性能和精度考虑

Question

考虑以下类:

public class Money {
    private double amount;

    public Money(double amount) {
        super();
        this.amount = amount;
    }

    public double getAmount() {
        return amount;
    }

    public void setAmount(double amount) {
        this.amount = amount;
    }

    public Money multiplyBy( int factor) {
        this.amount *= factor;
        return this;
    }
}

我可以采取哪些预防措施来确保此类在多线程方面没有任何问题。有良好的表现。同时确保货币精度不会出现问题

Answer 1

艾哈迈德，你的问题很模糊。

关于多线程:不清楚您所说的多线程问题是什么意思。例如，该类在同步良好的意义上没有任何多线程问题，但您仍然可以将 Money 对象的状态设置为困惑，由多个线程使用它:

public class Money {
    private volatile double amount;

    public Money(double amount) {
        super();
        this.amount = amount;
    }

    public double getAmount() {
        return amount;
    }

    public synchronized void setAmount(double amount) {
        this.amount = amount;
    }

    public synchronized Money multiplyBy( int factor) {
        this.amount *= factor;
        return this;
    }
}

关于货币精度:正如 Andreas 回答的那样，请参阅:Why not use Double or Float to represent currency? 。另外，这个可能很有趣:What is the best data type to use for money in Java app?