23集合框架

集合框架

 

12.集合框架

 

12.1接口

 

12.1.1 Collection

 

12.2列表

 

12.2.1List

 

需求:将朋友信息定义为一个对象,将对象加入List中并从List中显示

 

package com.Aha.Best;

 

public class Friend {

 

       private String name;

 

       private String emial;

 

       private String mobile;

 

       public String getName() {

 

           return name;

 

       }

 

       public void setName(String name) {

 

           this.name = name;

 

       }

 

       public String getEmial() {

 

           return emial;

 

       }

 

       public void setEmial(String emial) {

 

           this.emial = emial;

 

       }

 

       public String getMobile() {

 

           return mobile;

 

       }

 

       public void setMobile(String mobile) {

 

           this.mobile = mobile;

 

       }

 

}

 

package com.Aha.Best;

 

import java.util.*;

 

public class TestList {

 

//friendList是一个全局变量,用来存放所有的Friend对象

 

List friendList = new ArrayList();

 

public TestList() {

 

}

 

public void addFriend(Friend friend){

 

//调用add方法,往list中添加对象

 

friendList.add(friend);

 

}

 

public int getFriendSize(){

 

//size是list对象的一个方法

 

return friendList.size();

 

}

 

public void insertFriend(String name,String email,String mobile){

 

//新建一个Friend对象

 

Friend friend = new Friend();

 

friend.setName(name);

 

friend.setEmial(email);

 

friend.setMobile(mobile);

 

this.addFriend(friend);

 

}

 

public void showAllFriend(){

 

System.out.println("name " + "email " + "mobile");

 

System.out.println("---------------------------------");

 

Friend friend = new Friend();

 

//循环显示,list也是从0开始算起

 

for(int i = 0 ; i < this.getFriendSize(); i++){

 

friend = (Friend)friendList.get(i);

 

System.out.print(friend.getName() + " ");

 

System.out.print(friend.getEmial() + " ");

 

System.out.println(friend.getMobile() + " ");

 

}

 

System.out.println("---------------------------------");

 

System.out.println("size : " + this.getFriendSize());

 

}

 

public static void main(String[] args) {

 

TestList testList1 = new TestList();

 

//添加两条记录

 

testList1.insertFriend("holen","[email protected]","13910118302");

 

testList1.insertFriend("frank","[email protected]","13800008888");

 

testList1.showAllFriend();

 

}

 

}

 

12.2.2Vector

 

12.2.3ArrayList

 

12.2.4LinkedList

 

12.3集合

 

12.3.1Set

 

12.3.2SortedSet

 

12.3.3TreeSet

 

12.3.4HashSet

 

需求:将一些无序的对象置入一个对象集中。

 

import java.util.Hashtable;

 

public class TestHashTable {

 

Hashtable hashTable = new Hashtable();

 

String strObjectA = new String("this is ObjectA");

 

String strObjectB = new String("This is ObjectB");

 

Integer intObjectC = new Integer(2);

 

Integer intObjectD = new Integer(2345);

 

public TestHashTable() {

 

}

 

public void addObject(){

 

hashTable.put("my1",strObjectA);

 

hashTable.put(intObjectC,strObjectB);

 

hashTable.put(intObjectD,strObjectA);

 

hashTable.put("cgcg",intObjectC);

 

hashTable.put(strObjectA,intObjectC);

 

}

 

public void printHashtable(){

 

System.out.println(hashTable);

 

}

 

public static void main(String[] args) {

 

TestHashTable testHashTable1 = new TestHashTable();

 

testHashTable1.addObject();

 

testHashTable1.printHashtable();

 

}

 

}

 

12.4映射

 

12.4.1Map

 

12.4.2HashMap

 

12.4.3TreeMap

 

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转载自www.cnblogs.com/Aha-Best/p/10884536.html
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