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java 集合排序问题

有一串分数我存在了rationalList集合里,然后要求对分数按倒数大小对分数进行排序

ListrationalList = new ArrayList<>();
Collections.sort(rationalList,new InverseComparator());
public class InverseComparator implements Comparator {
// 比较两个分数倒数的大小
@Override
public int compare(Rational obj1, Rational obj2) {
Rational ra1 = obj1;
Rational ra2 = obj2;
int nm1 = obj1.getNumerator();
int dm1 = obj1.getDenominator();
ra1.setDenominator(nm1);
ra1.setNumerator(dm1);
    int nm2 = obj2.getNumerator();
    int dm2 = obj2.getDenominator();
    ra2.setDenominator(nm2);
    ra2.setNumerator(dm2);  //这里这样的话就改变了原来的分数,后面输出来的都是倒数,而不是原来的分数,怎么写呢要?
}
}

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蛮大人123 2016-06-13 14:02:51 2337 0
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  • 我说我不帅他们就打我,还说我虚伪
    public int compare(Rational obj1, Rational obj2) {
    
        int nm1 = obj1.getNumerator();
        int dm1 = obj1.getDenominator();
        Rational ra1 = null;
        try {
            ra1 = new Rational(dm1,nm1);
        } catch (IllegalRationalException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    
        int nm2 = obj2.getNumerator();
        int dm2 = obj2.getDenominator();
        Rational ra2 = null;
        try {
            ra2 = new Rational(dm2,nm2);
        } catch (IllegalRationalException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        //……这里用前面本身排序的compareTo();只是参数换成了两个比较
        }
    2019-07-17 19:35:48
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