小编Rob*_*ert的帖子

假设我有一个包含工人的列表,每个工人有3个字段:它的名称,他所在的部门(可以只是部门的名称或班级部门的对象)和他的工资.

Elvis       Software Engineering        1000
Samba       Mechanical Engineering      2000
Bamba       Industrial Engineering      3000
Bisli       Medical Engineering         4000
Kinder      Electrical Engineering      1000
Elvis       Software Engineering        9999

现在我想按名字对它们进行排序,并将结果放入队列中.然后将队列放在地图中,从底部到顶部排序,以便排序后我想要的结果是:

Bamba       Industrial Engineering      3000
Bisli       Medical Engineering         4000
Elvis       Software Engineering        1000
Elvis       Software Engineering        9999
Samba       Mechanical Engineering      2000
Kinder      Electrical Engineering      1000

我不允许使用Collection.sort(),因此我使用比较器按名称对工人进行排序,如果名称相同 - 按部门排序,如果部门相同 - 按类别排序薪水.这是我写的比较器:

    class WorkerComparatorByName implements Comparator<Worker<?>> {
    @Override
    public int compare(Worker<?> w1, Worker<?> w2) {
        int compareValue = w1.getName().compareTo(w2.getName());
        if (compareValue != 0)
            return compareValue;
        compareValue = …