Java数组排序Arrays_sort，Comparator接口的用法 (二)
利用Comparator接口对对象进行排序：
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Students类：
package com.seimma.arrays;
public class Students{
?
?private String name;?? //学员姓名
?private int age;?????? //学员年龄
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?public Students(){
??
?}
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?public Students(String name,int age){
??this.name=name;
??this.age=age;
?}
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?public String getName() {
??return name;
?}
?public void setName(String name) {
??this.name = name;
?}
?public int getAge() {
??return age;
?}
?public void setAge(int age) {
??this.age = age;
?}
}
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ByAgeComparator 排序类：
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package com.seimma.arrays;
import java.util.Comparator;
public class ByAgeComparator implements Comparator<Object> {
???? /**
????? * firstStudents 要比较的第一个对象
????? * secondStudnets 要比较的第二个对象
????? */
???? public int compare(Object firstStudents, Object secondStudnets) {
??? ? int firstAge=((Students)firstStudents).getAge();????? //取出第一个对象的值。?
????? int secondAge=((Students)secondStudnets).getAge();??? //取出第一个对象的值。
????? int threeAge=firstAge-secondAge;???? //进行比较
????? //第一个参数小于、等于或大于第二个参数时分别返回负整数、零或正整数
????? if (threeAge>0) {
??? ??return 1;
??? ? }
???????? if (threeAge<0) {
??? ??return -1;
??? ? }else {
??? ???? return 0;
??? ? }
??? }
}
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package com.seimma.arrays;
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import java.util.Arrays;
public class ArraysDemo {
?????? public static void main(String[] args) {
??????????? ?ArraysDemo sortArrays=new ArraysDemo();
?????????? ??sortArrays.sortObjectArray();
???? ?}
?
????? /**
???? * 对对象进行排序
???? */
??? public void sortObjectArray(){
??? ?Students stu1=new Students("Students1",1);
??? ?Students stu2=new Students("Students2",2);
??? ?Students stu3=new Students("Students3",3);
??? ?Students stu4=new Students("Students4",4);
??? ?Students stu5=new Students("Students5",5);
??? ?Students stu6=new Students("Students6",6);
??? ?
??? ?Students [] stus=new Students[]{stu3,stu5,stu1,stu6,stu2,stu4};
??? ?System.out.println("对对象排序前：");
??? ?for (int i = 0; i < stus.length; i++) {
???Students st=stus[i];
???System.out.println(st.getName());
??}
??? ?
??? ?System.out.println("对对象排序后：");
??? ?Arrays.sort(stus, new ByAgeComparator());
??? ?for (int i = 0; i < stus.length; i++) {
??? ??Students st=stus[i];
??? ??System.out.println(st.getName());
???
??}
??? }
?
}
