map,loop,forEach,iterator
loop a Map
public class Main {
public static void main(String [] args){
Map<String,Double> map = new HashMap<>();
map.put("2330",309D);
map.put("2317", 91.4);
map.put("3008", 4345D);
//iterator
Set<String> set = map.keySet();
Iterator<String> it = set.iterator();
while (it.hasNext()) {
String key = it.next();
System.out.printf("key:%s,value:%s\n", key, map.get(key));
}
//forEach
for (Map.Entry<String, Double> entry : map.entrySet()) {
System.out.println("key:" + entry.getKey() + ",value:" + entry.getValue());
}
//lamda forEach
map.forEach((u, v) -> System.out.println("key:" + u + ",value:" + v));
}
}
Reference：