Java中List的排序
第一种方法,就是list中对象实现Comparable接口,代码如下:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
|
public class Person implements Comparable<Person> { private String name; private Integer order; /** * @return the name */ public String getName() { return name; } /** * @param name * the name to set */ public void setName(String name) { this .name = name; } /** * @return the order */ public Integer getOrder() { return order; } /** * @param order * the order to set */ public void setOrder(Integer order) { this .order = order; } @Override public int compareTo(Person arg0) { return this .getOrder().compareTo(arg0.getOrder()); } } |
第二种方法,就是在重载Collections.sort方法,代码如下:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
|
public class Person { private String name; private Integer order; /** * @return the name */ public String getName() { return name; } /** * @param name * the name to set */ public void setName(String name) { this .name = name; } /** * @return the order */ public Integer getOrder() { return order; } /** * @param order * the order to set */ public void setOrder(Integer order) { this .order = order; } } |
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
|
public static void main(String[] args) { List<Person> listA = new ArrayList<Person>(); Person p1 = new Person(); Person p2 = new Person(); Person p3 = new Person(); p1.setName( "name1" ); p1.setOrder( 1 ); p2.setName( "name2" ); p2.setOrder( 2 ); p3.setName( "name3" ); p3.setOrder( 3 ); listA.add(p2); listA.add(p1); listA.add(p3); Collections.sort(listA, new Comparator<Person>() { public int compare(Person arg0, Person arg1) { return arg0.getOrder().compareTo(arg1.getOrder()); } }); for (Person p : listA) { System.out.println(p.getName()); } } |
两次执行的结果都是:
name1
name2
name3