import java.util.ArrayList; 
import java.util.Collections; 
import java.util.Comparator; 
import java.util.Iterator; 
import java.util.LinkedList; 
import java.util.TreeMap; 
 
 
 
public class Test2{ 
   
  public static void main(String[] args){ 
     
    /* 此處用ArrayList實現 
     * 
     * ArrayList<Student>al=new ArrayList<Student>(); 
    for(int i=20070301,j=10;i<=20070330;i++,j++) 
    { 
      al.add(new Student(i,(int) (40*Math.random()+60), "同學"+j)); 
    } 
     
    //ArrayList排序借助Collections中的sort()方法實現。 
    Collections.sort(al, new Sortbygrade()); 
    for(Student sd:al) 
    System.out.println(sd); 
     
    */ 
     
    LinkedList<Student> lt=new LinkedList<Student>(); 
    for(int i=20070301,j=10;i<=20070330;i++,j++) 
    { 
      lt.add(new Student(i,(int) (40*Math.random()+60), "同學"+j)); 
    } 
     
    //對鏈表排序 
    Collections.sort(lt, new Sortbygrade()); 
    //輸出鏈表 
    for(Student sd:lt) 
      System.out.println(sd); 
     
  } 
   
} 
 
 
 
//學生類 
class Student{ 
  int num,grade; 
  String name; 
   
  //構造函數 
  public Student(int num,int grade,String name){ 
     
    this.num=num; 
    this.name=name; 
    this.grade=grade; 
  } 
   
  //此處必須覆寫 
  public String toString(){ 
//   System.out.println("hi"); 
    return "學號："+this.num+"\t"+"姓名:"+this.name+"  "+"成績:"+this.grade; 
  } 
   
} 
 
//創(chuàng)建一個比較器類 
class Sortbygrade implements Comparator<Student>{ 
 
  @Override 
  public int compare(Student s1, Student s2) { 
     
    if(s1.grade>s2.grade) 
      return 1; 
    if(s1.grade<s2.grade) 
      return -1; 
    if(s1.grade==s2.grade) 
      return s1.name.compareTo(s2.name); 
    return 0;     
     
  } 
   
} 

for(int i=0;i<lt.size();i++) 
{ 
  Student s=lt.get(i); 
  System.out.println("學號："+s.num+"  姓名："+s.name+"  成績："+s.grade); 
} 

package com.package1; 
 
import java.util.*; 
 
public class StuScore { 
 
public static void main(String[] args) { 
 
  TreeSet<Student> ts=new TreeSet<Student>(new Com()); 
  //添加元素進去 
  for(int i=20070301,j=1;i<=20070330;i++,j++) 
  { 
    ts.add(new Student(i,"同學"+j,(int) (40*Math.random()+60))); 
  } 
 
  //迭代循環(huán)取出 
  Iterator<Student> it=ts.iterator(); 
  while(it.hasNext()) 
  { 
    Student o1=it.next(); 
    System.out.println("學號："+o1.num+" "+"姓名："+o1.name+" "+" "+"成績："+o1.grade); 
 
  } 
 
} 
} 
//學生類 
class Student  
{ 
int num; 
int grade; 
String name; 
 
 
public Student(int num, String name,int grade) 
{ 
  this.num=num; 
  this.name=name; 
  this.grade=grade; 
} 
} 
class Com implements Comparator 
{ 
 
@Override 
public int compare(Object o1, Object o2) { 
 
  Student s1=(Student) o1; 
  Student s2=(Student) o2; 
  if(s1.grade>s2.grade) 
    return 1; 
  if(s1.grade<s2.grade) 
    return -1; 
  if(s1.grade==s2.grade) 
  { 
    return new Integer(s1.num).compareTo(new Integer(s2.num)); 
  } 
  return 0; 
} 
} 

package com.package1; 
 
import java.util.*; 
 
 
 
 
public class StuScore { 
 
  public static void main(String[] args) { 
     
    HashSet<Student> hs=new HashSet<Student>(); 
    //添加元素進去 
    for(int i=20070301,j=1;i<=20070330;i++,j++) 
    { 
     
      hs.add(new Student(i,"同學"+j,(int)  
 
(40*Math.random()+60))); 
    } 
     
    ArrayList<Student>li=new ArrayList(hs); 
     
    Collections.sort(li, new Sortbygrade()); 
     
    for(Student ss:li) 
      System.out.println(ss); 
     
 
  } 
 
} 
//學生類 
class Student  
{ 
  int num; 
  int grade; 
  String name; 
 
   
  public Student(int num, String name, int grade) 
  { 
    this.num=num; 
    this.name=name; 
    this.grade=grade; 
  } 
  public String toString(){ 
    //System.out.println("hi"); 
    return "學號："+this.num+"\t"+"姓名:"+this.name 
 
+"  "+"成績:"+this.grade; 
  } 
   
   
} 
 
 
class Sortbygrade implements Comparator{ 
 
  @Override 
  public int compare(Object o1, Object o2) { 
     
    Student s1=(Student) o1; 
    Student s2=(Student) o2; 
    if(s1.grade>s2.grade) 
      return 1; 
    if(s1.grade<s2.grade) 
      return -1; 
//   if(s1.grade==s2.grade) 
     
    return 0; 
  } 
   
} 

package com.package1;  
 
import java.util.Comparator; 
import java.util.Iterator; 
import java.util.Set; 
import java.util.TreeMap; 
 
public class TestTreeMap { 
 
  public static void main(String[] args) { 
    //1.創(chuàng)建集合 
    TreeMap<Student,Integer> tm=new TreeMap<Student,Integer>(); 
    for(int i=20070301,j=10;i<=20070330;i++,j++) 
    { 
      int grade=(int) (40*Math.random()+60); 
       //2、往集合對象中添加元素 
       tm.put(new Student(grade,"同學"+j),i); 
    } 
     
    //3.遍歷集合 ，排序完成  
    Set<Student> k=tm.keySet(); 
    Iterator<Student> it=k.iterator(); 
     
    while(it.hasNext()){ 
      Student key=it.next(); 
      Integer num=tm.get(key); 
       
      System.out.println("學號："+num+"  "+"姓名："+key.name+"  "+"成績:"+key.grade); 
    } 
  } 
 
} 
 
class Student implements Comparable<Student>{ 
  int grade; 
  String name; 
   
  public Student(int grade,String name){ 
    this.grade =grade; 
    this.name=name; 
  } 
 
  @Override 
  public int compareTo(Student o) { 
     
    if(this.grade>o.grade)  
      return 1;  
      if(this.grade==o.grade)  
      { //當成績相同時，按照姓名排序 
       return this.name.compareTo(o.name);  
      }  
      return -1;  
 
  } 
   
 
   
}