package Demo08_01;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Random;
import java.util.Set;
/**将26个字母抽取10个存入Map中
* @author admin
*
*/
public class demoMap {
/*26个字母随机抽取10个存入到Map中,再从Map中取出key-value
* @param args
*/
public static void main(String[] args) {
HashMap<Integer,Character> hs=new HashMap<>();
Random ra=new Random();
for (int i = 0; ; i++) {
int n=ra.nextInt(100)%26;
int t='A'+n;
hs.put(t, (char)t);
if(hs.size()==10)break;
}
System.out.println("方法一利用增强for循环遍历Map:");
for (Entry<Integer,Character> en : hs.entrySet()) {
Integer key = en.getKey();
Integer i=en.getKey();
Character value = en.getValue();
System.out.print(i+":"+value+"\t");
}
System.out.println();
System.out.println("************");
System.out.println("方法二利用迭代器遍历Map:");
//map遍历,将entry<key,value>放到set集合中,再遍历set集合
Set<Map.Entry<Integer, Character>> keyset1=hs.entrySet();
//初始化iterator对象
Iterator<Entry<Integer, Character>> iter=keyset1.iterator();
while(iter.hasNext()) {
Map.Entry<Integer, Character> entry=iter.next();
System.out.print(entry.getKey()+":"+entry.getValue()+"\t");
}
}
}