map的两种遍历

Map<String, Customer> customerMap = new HashMap<>();

//遍历entrySet
for (Map.Entry<String,Customer> m : customerMap.entrySet()){
m.getValue();//value值
m.getKey();key值
}

//遍历keySet
for (String s : customerMap.keySet()){
customerMap.get(s);//value值
}