java8 merge合并两个map，key相同value相加

		Map<String,Integer> map1= new HashMap<String, Integer>();
		map1.put("one",1);
		map1.put("two",2);
		map1.put("three",3);
		Map<String,Integer> map2= new HashMap<String,Integer>();
		map2.put("one",1);
		map2.put("two",2);
		//map1合并到map2中
		map1.forEach((key,value) -> map2.merge(key,value,Integer::sum));
		System.out.println(JSON.toJSONString(map2));

结果：{"one":2,"three":3,"two":4}

来源：CSDN

作者：df331009

链接：https://blog.csdn.net/df331009/article/details/104225770