Java程序将所有键值对从一个Map复制到另一个Map
若要复制，请使用putAll()方法。
让我们首先创建两个Map-
第一张映射-
HashMap hm = new HashMap();
hm.put("Wallet", new Integer(700));
hm.put("Belt", new Integer(600));第二张映射-
HashMap hm2 = new HashMap();
hm.put("Bag", new Integer(1100));
hm.put("Sunglasses", new Integer(2000));
hm.put("Frames", new Integer(800));现在，将键值对从一个Map复制到另一个Map-
hm.putAll(hm2);
以下是将所有键值对从一个Map复制到另一个Map的示例-
示例
import java.util.*;
public class Demo {
public static void main(String args[]) {
//创建哈希映射1-
HashMap hm = new HashMap();
hm.put("Wallet", new Integer(700));
hm.put("Belt", new Integer(600));
System.out.println("Map1 = "+hm);
//创建哈希映射2-
HashMap hm2 = new HashMap();
hm.put("Bag", new Integer(1100));
hm.put("Sunglasses", new Integer(2000));
hm.put("Frames", new Integer(800));
hm.putAll(hm2);
System.out.println("Map1 after copying values of Map2 = "+hm);
}
}输出结果
Map1 = {Belt=600, Wallet=700}
Map1 after copying values of Map2 = {Frames=800, Belt=600, Wallet=700, Bag=1100, Sunglasses=2000}