Map接口相关实验.doc

例1import java.util.*;public class studentTest public static void main(String args) Map students=new HashMap(); Student s1=new Student(黎明,香港大学); Student s2=new Student(郭富城,台湾大学); Student s3=new Student(刘德华,香港大学); Student s4=new Student(张学友,台湾大学); students.put(Leon, s1); students.put(Aaron Kwok , s2); students.put(AndyLau, s3); students.put(Jacky Cheung, s4); System.out.println(当前Map中元素的个数为：); System.out.println(students.size(); System.out.println(students.keySet(); System.out.println(students.values(); System.out.println(students); System.out.println(Leon对应的Values值为：); if(students.containsKey(Leon) System.out.println(students.get(Leon); students.remove(Leon); System.out.println(删除掉Leon之后：); System.out.println(students.entrySet(); System.out.println(当前Map中元素的个数为：); System.out.println(students.size(); public class Student private String name; private String gradue; public Student(String name,String gradue) =name; this.gradue=gradue; public String toString() return 姓名+name+毕业学校+gradue; public String getName() return name;public void setName(String name) = name;public String getGradue() return gradue;public void setGradue(String gradue) this.gradue = gradue; 例2import java.util.Collection;import java.util.HashMap;import java.util.Iterator;import java.util.Map;/* *本示例演示link HashMap类的用法HashMap的定义:以键值对的形式存放数据特点：key是不能重复的优点:提供了快速的检索方案HashMap的数据存取:link HashMap#put(key,value)、link HashMap#get(key)HashMap的迭代:借助Set 调用values方法得到存放了所有值的Collection在本例中还演示了泛型的用法：泛型意味着更好的类型安全性情景：希望所有的仓库像数组一样，只存放某种类型的物品。每次拿东西时都知道究竟取出来的是什么。在声明时，在类型后多了在取出时，省去了令人头疼的转型*/public class MapTest public static void main(String args) Map dogHouse=new HashMap();/此处使用了泛型Dog dahuang=new Dog(大黄,2,黄色的,公狗);Dog huahua=new Dog(花花,1,红色的,母狗);Dog xixi=new Dog(西西,3,白色的,公狗);/一对对的放进去dogHouse.put(大黄, dahuang);dogHouse.put(花花, huahua); dogHouse.put(西西, xixi); Dog dog=dogHouse.get(大黄);/用了泛型，取出来的就是狗，无需类型转换System.out.println(大黄对应的Values是：); dog.bark();/Map转换为CollectionCollection dogColleciton=dogHouse.values();/迭代输出Iterator dogIterator=dogColleciton.iterator();while(dogIterator.hasNext()(Dog)dogIterator.next().bark();class Dog private String name;/ 名字private int age;/ 年龄private String furColor;/ 毛色private String xingbie;/ 性别public Dog(String name, int age, String furColor, String xingbie) super(); = name;this.age = age;this.furColor = furColor;this.xingbie = xingbie;public String getXingbie() return xingbie;public void setXingbie(String xingbie) this.xingbie = xingbie;public String getName() return name;public void setName(String name) = name;public int getAge() return age;public void setAge(int age) this.age = age;public String getFurColor() return furColor;public void setFurColor(String furColor) this.furColor = furColor;public void bark() System.out.println(我是一只 + getFurColor() + getXingbie() + 小狗，我的名字+ getName() + 我 + getAge() + 岁了);例3import Java.util.*; class Student private String name; / 学员姓名private String school; / 中心名称public Student(String name, String school) = name;this.school = school;public String toString() return school+毕业的+name;public class TestMap public static void main(String args) Student student1 = new Student(李明, 西苑中心);Student student2 = new Student(刘丽, 西苑中心);Student student3 = new Student(张娜, 马甸中心);Student student4 = student1; Map students = new HashMap(); students.put(Jack, student1); students.put(Rose, student2); students.put(Mary, student3); students.put(Rose, student4); System.out.println(键集：+students.keySet(); System.out.println(值集：+students.values(); 例4import java.util.*;public class Test public static void main(String args) Map yourMap = new HashMap();yourMap.put(3, c);yourMap.put(4, d);yourMap.put(1, a);yourMap.put(2, b);Map map = new LinkedHashMap();List keyList = new ArrayList(yourMap.keySet();List valueList = new ArrayList(yourMap.values();Set sortedSet = new TreeSet(valueList);Object sortedArray = sortedSet.toArray();int size = sortedArray.length;for (int i = 0; i size; i+