技術標籤：介面java快速排序

比較器一般在類外使用

package Comparator;
import java.util.Comparator;
public class NameComparator implements Comparator{
//實現Comparator介面並重寫compare方法
@Override
public int compare(Student o1, Student o2) {
//按姓名首字母排序
return o1.name.compareTo(o2.name);
}
}

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package Comparator;
import java.util.Comparator;
public class SorceComparator implements Comparator {
//實現Comparator介面並重寫compare方法
@Override
public int compare(Student o1, Student o2) {
//成績按從低到高排序
return o1.sorce-o2.sorce;
//等價
/if(o1.score > o2.score) {
return 1;
}else if(o1.score == o2.score) {
return 0;

=============================================
package Comparator;
import java.util.Arrays;
class Student {
public String name;
public int sorce;

 Student(String name, int sorce) {
     this.name = name;
     this.sorce = sorce;
 }

 @Override  //重寫toString方法
 public String toString() {
     return "student{" +
             "name='" + name + '\'' +
             ", sorce=" + sorce +
             '}';
 }

}
public class Test {
public static void main(String[] args) {
Student[] student=new Student[3]; //建立一個Student類的陣列將所以Student物件都存入
student[0]=new Student(“ZhangSan”,85);
student[1]=new Student(“LiSi”,95);
student[2]=new Student(“WangWu”,75);
System.out.println(Arrays.toString(student));
System.out.println("=按姓名排序====");
NameComparator nameComparator=new NameComparator();
Arrays.sort(student,nameComparator);
System.out.println(Arrays.toString(student));
System.out.println("=按成績排序====");
SorceComparator sorceComparator=new SorceComparator();
Arrays.sort(student,sorceComparator);
System.out.println(Arrays.toString(student));
}
}

=============================================
執行結果如下