在Java中查找HashMap的大小
使用该size()方法获取HashMap的大小。让我们首先创建一个HashMap
HashMap hm = new HashMap();
现在，添加一些元素-
hm.put("Bag", new Integer(1100));
hm.put("Sunglasses", new Integer(2000));
hm.put("Franes", new Integer(800));
hm.put("Wallet", new Integer(700));
hm.put("Belt", new Integer(600));由于我们在上面添加了5个元素，因此，该size()方法将得出5个结果-
set.size()
以下是查找HashMap大小的示例-
示例
import java.util.*;
public class Demo {
public static void main(String args[]) {
//创建一个哈希映射
HashMap hm = new HashMap();
//将元素放入映射
hm.put("Bag", new Integer(1100));
hm.put("Sunglasses", new Integer(2000));
hm.put("Franes", new Integer(800));
hm.put("Wallet", new Integer(700));
hm.put("Belt", new Integer(600));
Set set = hm.entrySet();
System.out.println("Elements in HashMap...");
//获取一个迭代器
Iterator i = set.iterator();
//显示元素
while(i.hasNext()) {
Map.Entry me = (Map.Entry)i.next();
System.out.print(me.getKey() + ": ");
System.out.println(me.getValue());
}
System.out.println();
System.out.println("Size of HashMap = "+set.size());
}
}输出结果
Elements in HashMap... Franes: 800 Belt: 600 Wallet: 700 Bag: 1100 Sunglasses: 2000 Size of HashMap = 5