@@ -13,7 +13,9 @@ public class LambdaComparatorDemo {
1313 public static String [] arrays = {"Milan" , "london" , "San Francisco" , "Tokyo" , "New Delhi" };
1414
1515 public static void main (String [] args ) {
16- test01 ();
16+ // test01();
17+ // test02();
18+ test03 ();
1719 }
1820
1921 /**
@@ -38,6 +40,69 @@ public static void test01() {
3840 .forEach (System .out ::println );
3941 }
4042
43+ /**
44+ * 对整数数组进行排序
45+ */
46+ public static void test02 () {
47+ List <Integer > numbers = Arrays .asList (6 , 2 , 4 , 3 , 1 , 9 );
48+ System .out .println (numbers );
49+ 50+ // 自然排序(升序)
51+ numbers .sort (Comparator .naturalOrder ());
52+ System .out .println (numbers );
53+ 54+ // 降序
55+ numbers .sort (Comparator .reverseOrder ());
56+ System .out .println (numbers );
57+ }
58+ 59+ /**
60+ * 对对象进行排序
61+ */
62+ public static void test03 () {
63+ Employee e1 = new Employee (1 ,23 ,"M" ,"Rick" ,"Beethovan" );
64+ Employee e2 = new Employee (2 ,13 ,"F" ,"Martina" ,"Hengis" );
65+ Employee e3 = new Employee (3 ,43 ,"M" ,"Ricky" ,"Martin" );
66+ Employee e4 = new Employee (4 ,26 ,"M" ,"Jon" ,"Lowman" );
67+ Employee e5 = new Employee (5 ,19 ,"F" ,"Cristine" ,"Maria" );
68+ Employee e6 = new Employee (6 ,15 ,"M" ,"David" ,"Feezor" );
69+ Employee e7 = new Employee (7 ,68 ,"F" ,"Melissa" ,"Roy" );
70+ Employee e8 = new Employee (8 ,79 ,"M" ,"Alex" ,"Gussin" );
71+ Employee e9 = new Employee (9 ,15 ,"F" ,"Neetu" ,"Singh" );
72+ Employee e10 = new Employee (10 ,45 ,"M" ,"Naveen" ,"Jain" );
73+ 74+ List <Employee > employees = Arrays .asList (e1 , e2 , e3 , e4 , e5 , e6 , e7 , e8 , e9 , e10 );
75+ 76+ // 根据employee的年龄进行自然排序
77+ employees .sort (Comparator .comparing (Employee ::getAge ));
78+ employees .forEach (System .out ::println );
79+ 80+ System .out .println ();
81+ 82+ // 根据employee的年龄进行降序排序
83+ employees .sort (Comparator .comparing (Employee ::getAge ).reversed ());
84+ employees .forEach (System .out ::println );
85+ 86+ System .out .println ();
87+ 88+ // 先对性别排序,然后对年龄进行排序
89+ employees .sort (
90+ Comparator .comparing (Employee ::getGender )
91+ .thenComparing (Employee ::getAge )
92+ // 性别,年龄都进行倒序排序
93+ .reversed ()
94+ );
95+ employees .forEach (System .out ::println );
96+ 97+ // 自定义排序器
98+ employees .sort ((em1 , em2 ) -> {
99+ if (em1 .getAge ().equals (em2 .getAge ())) {
100+ return 0 ;
101+ }
102+ return em1 .getAge () - em2 .getAge () > 0 ? -1 : 1 ;
103+ });
104+ employees .forEach (System .out ::println );
105+ }
41106
42107
43108
@@ -62,7 +127,7 @@ public static void test01() {
62127
63128 @ Data
64129 @ AllArgsConstructor
65- public class Employee {
130+ public static class Employee {
66131
67132 private Integer id ;
68133 // 年龄
@@ -71,5 +136,16 @@ public class Employee {
71136 private String gender ;
72137 private String firstName ;
73138 private String lastName ;
139+ 140+ @ Override
141+ public String toString () {
142+ return "Employee{" +
143+ "id=" + id +
144+ ", age=" + age +
145+ ", gender='" + gender + '\'' +
146+ ", firstName='" + firstName + '\'' +
147+ ", lastName='" + lastName + '\'' +
148+ '}' ;
149+ }
74150 }
75151}
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