根據list中對象的某個屬性排序

排序前：1,3,5,2,4,
排序後：1,2,3,4,5,

    public static void main(String[] args) {
        List<SysCompany> companyList = new ArrayList<>();
        SysCompany c1 = new SysCompany();
        c1.setSort(1);
        SysCompany c2 = new SysCompany();
        c2.setSort(2);
        SysCompany c3 = new SysCompany();
        c3.setSort(3);
        SysCompany c4 = new SysCompany();
        c4.setSort(4);
        SysCompany c5 = new SysCompany();
        c5.setSort(5);

        companyList.add(c1);
        companyList.add(c3);
        companyList.add(c5);
        companyList.add(c2);
        companyList.add(c4);

        for (SysCompany c:companyList)
            System.out.print(c.getSort()+",");

        System.out.println();
        Collections.sort(companyList, new Comparator<SysCompany>() {
            public int compare(SysCompany c1, SysCompany c2) {
                //降序
//                    return c2.getSort().compareTo(c1.getSort());
                //升序
                return c1.getSort().compareTo(c2.getSort());
            }
        });
        for (SysCompany c:companyList)
            System.out.print(c.getSort()+",");
    }