[20160725]MyComparableTest

知识点：

1、Collections的使用。

2、自定义类泛型的使用。

3、自定义类，toString();equals();hashCode()方法的重写。

import java.util.*;

public class MyComparableTest{
  public static void main(String[] args) {
    List<Name> a=new LinkedList<Name>();
    a.add(new Name("shang","zeng"));
    a.add(new Name("qi","li"));
    a.add(new Name("mei","niang"));
    a.add(new Name("peingfei","chen"));

    System.out.println(a);
    Collections.sort(a);
    System.out.println(a);


    System.out.println(a.remove(new Name("peingfei","chen")));
    System.out.println(a);

  }
}

class Name implements Comparable<Name>{
  String firstname,lastname;

  public Name(String firstname,String lastname){
    this.firstname=firstname;
    this.lastname=lastname;
  }

    public String toString(){
     return(firstname+" "+lastname);
  }

/* //equals()method one
  public boolean equals(Object obj){
    if (obj==null){  return false;  }
    else
       { if(obj instanceof Name)
             {
               Name n = (Name)obj;
               if (this.firstname.equals(n.firstname) && this.lastname.equals(n.lastname)){return true;}
             }

        return false;
       }
  }
*/
  // equals()methoed two
public boolean equals(Object obj){
   if(obj instanceof Name){
     Name n=(Name)obj;
     return (this.firstname.equals(n.firstname))
         && (this.lastname.equals(n.lastname));
   }

    return super.equals(obj);
}

  public int hashCode(){  return firstname.hashCode();  }

   public int compareTo(Name o){
     int lastnamecompare=lastname.compareTo(o.lastname);
     return
         (lastnamecompare!=0?lastnamecompare:firstname.compareTo(o.firstname));
   }
}