import java.util.*;
class Student implements Comparable<Student>
{
private String name;
private int age;
Student(String name,int age)
{
  this.name=name;
  this.age=age;
}
public int hashCode()
{
  return name.hashCode()+age*34;
}
public boolean equals(Object obj)
{
  if(!(obj instanceof Student))
   throw new ClassCastException("类型不匹配");
   Student s=(Student)obj;
  return this.name.equals(s.name) && this.age==s.age;
}
public String getName()
{
  return name;
}
public int getAge()
{
  return age;
}
public int compareTo(Student s)
{
  int num= new Integer(this.age).compareTo(new Integer(s.age));
  if(num==0)
   return this.name.compareTO(s.name);
  return num;
}
public String toString()
{
  return name+":"+age;
}
}
class MapTest
{
public static void main(String[] args)
{
  HashMap<Student,String> hm=new HashMap<Student,String>();
  hm.put(new Student("lisi1",21),"beijing");
   hm.put(new Student("lisi2",22),"shanghai");
   hm.put(new Student("lisi3",23),"xian");
   hm.put(new Student("lisi4",24),"nanjing");
   Set<Student> keySet=hm.keySet();
  Iterator<Student> it=keySet.Iterator();
  while(it.hasNext())
  {
   Student stu=it.next();
   String addr=hm.get(stu);
   System.out.println(stu+":"+addr);
  }
}
} 求指教

1. import java.util.*;
   
2. class Student implements Comparable<Student>
   
3. {
   
4. private String name;
   
5. private int age;
   
6. Student(String name,int age)
   
7. {
   
8.   this.name=name;
   
9.   this.age=age;
   
10. }
    
11. public int hashCode()
    
12. {
    
13.   return name.hashCode()+age*34;
    
14. }
    
15. public boolean equals(Object obj)
    
16. {
    
17.   if(!(obj instanceof Student))
    
18.    throw new ClassCastException("类型不匹配");
    
19.    Student s=(Student)obj;
    
20.   return this.name.equals(s.name) && this.age==s.age;
    
21. }
    
22. public String getName()
    
23. {
    
24.   return name;
    
25. }
    
26. public int getAge()
    
27. {
    
28.   return age;
    
29. }
    
30. public int compareTo(Student s)
    
31. {
    
32.   int num= new Integer(this.age).compareTo(new Integer(s.age));
    
33.   if(num==0)
    
34.    return this.name.compareTo(s.name);//这里注意，应该是compareTo
    
35.   return num;
    
36. }
    
37. public String toString()
    
38. {
    
39.   return name+":"+age;
    
40. }
    
41. }
    
42. class MapTest
    
43. {
    
44. public static void main(String[] args)
    
45. {
    
46.   HashMap<Student,String> hm=new HashMap<Student,String>();
    
47.   hm.put(new Student("lisi1",21),"beijing");
    
48.    hm.put(new Student("lisi2",22),"shanghai");
    
49.    hm.put(new Student("lisi3",23),"xian");
    
50.    hm.put(new Student("lisi4",24),"nanjing");
    
51.    Set<Student> keySet=hm.keySet();
    
52.   Iterator<Student> it=keySet.iterator();//iterator开头是小写
    
53.   while(it.hasNext())
    
54.   {
    
55.    Student stu=it.next();
    
56.    String addr=hm.get(stu);
    
57.    System.out.println(stu+":"+addr);
    
58.   }
    
59. }
    
60. }

复制代码

都是些小问题，以后仔细一点

问题已解决

郑小杰 发表于 2012-8-8 11:03
都是些小问题，以后仔细一点

粗心了~~以后一定注意

问题已解决