java - 有没有办法让 JScience 输出为 "human friendly"格式？

Question

当我对 JScience Amount 对象使用 toString() 时，我得到如下结果:

(7.5 ± 4.4E-16) mph

这并不糟糕，但我真的希望它输出如下内容:

7.5 miles per hour

有没有简单的方法可以做到这一点？

编辑:只是为了澄清，我希望有一个解决方案适用于任何金额和任何类型的单位(或至少所有预定义的单位)，而不仅仅是“英里/小时”。

Answer 1

尽管它会丢弃错误和单位，但您可以执行以下操作:

Amount<Velocity> x = Amount.valueOf(7.5, NonSI.MILES_PER_HOUR);
System.out.println(x);
System.out.println(
    x.doubleValue(NonSI.MILES_PER_HOUR) + " miles per hour");

控制台:

(7.5 ± 4.4E-16) mph7.5 miles per hour

Addendum: I'm hoping for a solution that works for any amount with any units.

You'll still have to provide your own label to replace the default UnitFormat; the label characters are limited by isValidIdentifier(). You can also substitute your own AmountFormat, as suggested by @Roger Lindsjö. This example prints an arbitrary number of significant digits of the estimated value and a valid variation of your label. See also TypeFormat.

final UnitFormat uf = UnitFormat.getInstance();
uf.label(NonSI.MILES_PER_HOUR, "miles_per_hour");
AmountFormat.setInstance(new AmountFormat() {

    @Override
    public Appendable format(Amount<?> m, Appendable a) throws IOException {
        TypeFormat.format(m.getEstimatedValue(), -1, false, false, a);
        a.append(" ");
        return uf.format(m.getUnit(), a);
    }

    @Override
    public Amount<?> parse(CharSequence csq, Cursor c) throws IllegalArgumentException {
        throw new UnsupportedOperationException("Parsing not supported.");
    }
});
Amount<Velocity> x = Amount.valueOf(7.5, NonSI.MILES_PER_HOUR);
System.out.println(x);

控制台:

7.5 miles_per_hour