实现场景：集合对象按照自定义规则排序【代码】

原理：

　　利用Collections.sort的自定义排序功能 + 自己写一个确定对象字段下标的方法，判断下标的大小确定自定义顺序。

public class TestCollection {
    String yearOrder = "全网,广东,广西,云南,贵州,海南,广州,深圳";

    @Autowired
    private DlgyIndexYearMapper dlgyIndexYearMapper;
    
    public int getIndex(String order, String value) {
        if (order != null && value != null) {
            return order.indexOf(value);
        }else {
            return 100;
        }
    }
    
    public List<DlgyIndexYear> sort(List<DlgyIndexYear> list) {
        if (list != null) {
            Collections.sort(list, new Comparator<DlgyIndexYear>() {
                public int compare(DlgyIndexYear o1, DlgyIndexYear o2) {
                    int index_1 = new TestCollection().getIndex(yearOrder, o1.getType1());
                    int index_2 = new TestCollection().getIndex(yearOrder, o2.getType1());
                    return index_1 - index_2;
                };
            });
            return list;
        }else {
            return null;
        }
    }
    
    @Test
    public void run() {
        DlgyIndexYearExample dlgyIndexYearExample = new DlgyIndexYearExample();
        Criteria createCriteria = dlgyIndexYearExample.createCriteria();
        createCriteria.andPdateEqualTo("2020");
        
        List<DlgyIndexYear> selectByExample = dlgyIndexYearMapper.selectByExample(dlgyIndexYearExample);
        
        TestCollection testCollection = new TestCollection();
        List<DlgyIndexYear> sort = testCollection.sort(selectByExample);
        
        for (DlgyIndexYear dlgyIndexYear : sort) {
            System.out.println(dlgyIndexYear.toString());
        }
    }
}