合并list并且按照时间去排序

1、实体类实现Comparable接口

public class ExpertCounselListDTO implements Comparable<ExpertCounselListDTO>{
	private Date createDate;
	@Override
	public int compareTo(ExpertCounselListDTO arg0) {
        return this.getCreateDate().compareTo(arg0.getCreateDate());
	}
}

2、代码

	List<ExpertCounselListDTO> list = expertCounselService.selectMyCounselList(userId);

	List<ExpertCounselListDTO> mediateList = mediateService.selectByUserId(userId);
	
	compareList.addAll(mediateList);
	compareList.addAll(list);
	Collections.sort(compareList);

3、over