1、public class Dog implements Cloneable,Comparable<Dog> { 2 3 private String name; 4 private String age; 5 6 public String getName() { 7 return name; 8 } 9 public void setName(String name) {10 this.name = name;11 }12 public String getAge() {13 return age;14 }15 public void setAge(String age) {16 this.age = age;17 }18 public Dog(String name, String age) {19 super();20 this.name = name;21 this.age = age;22 }23
2、 public Dog() {24 super();25 }26 @Override27 public String toString() {28 return "Dog [name=" + name + ", age=" + age + "]";29 }30 31 public Object clone() throws CloneNotSupportedException {32 33 return super.clone();34 }35 @Override36 public int compareTo(Dog o) {37 38 return this.getName().compareTo(o.getName());39 }40 }
3、测试类
1 public class Test { 2 3 public static void main(String[] args) { 4 List<Dog> list = new ArrayList<Dog>(); 5 Dog d1 = new Dog("cac", "11"); 6 Dog d2 = new Dog("bac", "11"); 7 Dog d3 = new Dog("aac", "11"); 8 Dog d4 = new Dog("eac", "11"); 9 list.add(d1);10 list.add(d2);11 list.add(d3);12 list.add(d4);13 // MyCompare mc = new MyCompare();14 // Collections.sort(list,mc);15 Collections.sort(list);16 for (Dog dog : list) {17 System.out.println(dog);18 }19 20 }21 }
4、结果：
Dog [name=aac, age=11]Dog [name=bac, age=11]Dog [name=cac, age=11]Dog [name=eac, age=11]
自定义比较器，Collections.sort(List list，Comparator<T> compare)，创建比较器类实现接口
1 public class Test { 2 3 public static void main(String[] args) { 4 List<Dog> list = new ArrayList<Dog>(); 5 Dog d1 = new Dog("cac", "11"); 6 Dog d2 = new Dog("bac", "11"); 7 Dog d3 = new Dog("aac", "11"); 8 Dog d4 = new Dog("eac", "11"); 9 list.add(d1);10 list.add(d2);11 list.add(d3);12 list.add(d4);13 MyCompa
5、re mc = new MyCompare();14 Collections.sort(list,mc);15 for (Dog dog : list) {16 System.out.println(dog);17 }18 19 }20 }21 22 class MyCompare implements Comparator<Dog>{23 24 @Override25 public int compare(Dog d1, Dog d2) {26 String s1 = d1.getName();27 String s2 = d2.getName();28 if(s1.equals(s2))29 return 0;30 else {31 return s1.compareTo(s2);32 }33 }34 35 }
结果：
Dog [name=aac, age=11]Dog [name=bac, age=11]Dog [name=cac, age=11]Dog [name=eac, age=11]
