想将数据库中的记录按时间排序,一条记录中时间字段类型是String,如2000-01-01 20:20:20
先给你一个list,list是所有记录的集合(注意,不是时间集合),所以估计还先把每条记录的时间提取出来,再排序,最后得到按时间排序的新的list。
哪位高手帮忙解答?
先给你一个list,list是所有记录的集合(注意,不是时间集合),所以估计还先把每条记录的时间提取出来,再排序,最后得到按时间排序的新的list。
哪位高手帮忙解答?
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.List;public class Test { public static class Man { private String birthday;
private String name; public Man() {
} public Man(String name, String birthday) {
this.name = name;
this.birthday = birthday;
} @Override
public String toString() {
return name + " " + birthday;
} public String getName() {
return name;
} public void setName(String name) {
this.name = name;
} public String getBirthday() {
return birthday;
} public void setBirthday(String birthday) {
this.birthday = birthday;
}
} public static void main(String[] args) {
List<Man> list = new ArrayList<Man>();
list.add(new Man("张三", "2000-01-01 20:20:20"));
list.add(new Man("李四", "2001-01-01 20:20:20"));
list.add(new Man("王五", "2005-05-01 20:20:20"));
list.add(new Man("BBB", "2003-01-01 20:20:20")); System.out.println("排序前:" + list);
Collections.sort(list, new Comparator<Man>() { SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); private Date getBirthday(Man m) {
if (m == null || m.getBirthday() == null)
return null;
try {
return sdf.parse(m.getBirthday());
} catch (ParseException e) {
return null;
}
} public int compare(Man o1, Man o2) {
Date d1 = getBirthday(o1);
Date d2 = getBirthday(o2);
if (d1 == null && d2 == null)
return 0; if (d1 == null)
return -1;
if (d2 == null)
return 1;
return d1.compareTo(d2);
} });
System.out.println("排序后:" + list);
}}
public List sortList(List list) {
Collections.sort(list, new Comparator<Man>() { SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); private Date getBirthday(Man m) {
if (m == null || m.getBirthday() == null)
return null;
try {
return sdf.parse(m.getBirthday());
} catch (ParseException e) {
return null;
}
} public int compare(Man o1, Man o2) {
Date d1 = getBirthday(o1);
Date d2 = getBirthday(o2);
if (d1 == null && d2 == null)
return 0; if (d1 == null)
return -1;
if (d2 == null)
return 1;
return d1.compareTo(d2);
} });
}借用一楼的。把list放进去,改下你的对象名和日期,这样也不能满足?
Collections.sort(list,new Comparator<Test>(){
public int compare(Testarg0, Test arg1) {
return arg0.getDate().compareTo(arg1.getDate());
}
});Test是你自己定义的数据类
public class Test{
String name;
Date date;
}
Date
list里放的是Man类的实例呀。