import java.util.*;public class Student implements Comparable...{ private String name; private int age; private int score; public Student()...{} public Student(String name,int age,int score)...{ this.name = name; this.age = age; this.score = score; } public void setName(String name)...{ this.name = name; } public String getName()...{ return this.name; } public void setAge(int age)...{ this.age = age; } public int getAge()...{ return this.age; } public void setScore(int score)...{ this.score = score; } public int getScore()...{ return this.score; } @Override public String toString()...{ return this.name + " " + age +" "+score; } // public boolean equals(Student stu) {// boolean flag = false;// if(stu.name.equals(this.name) && stu.age == this.age){// flag = true;// }// return flag;// } public int compareTo(Object stu) ...{// int i = age - ((Student)stu).getAge(); int j =this.name.compareTo(((Student)stu).getName()); return j; } public static ArrayList sort(ArrayList al)...{ ArrayList tmp = new ArrayList(); for (Object objs:al)...{ tmp.add(objs); } Object[] obj = tmp.toArray(); Arrays.sort(obj); tmp.clear(); for (int i = 0;i<obj.length;i++)...{ tmp.add(obj[i]); } return tmp; } }