为什么日期从Key中获得
for (String key : copy.keySet()) {
Date date = copy.get(key);//日期值不是在value当中吗？？？
int month = date.getMonth() + 1;
if (month == 6 || month == 7 || month == 8) {
map.remove(key);
package zh.codegym.task.task08.task0816;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Locale;
/*
善良的艾玛和暑假
*/
public class Solution {
public static HashMap<String, Date> createMap() throws ParseException {
DateFormat df = new SimpleDateFormat("MMMMM d yyyy", Locale.ENGLISH);
HashMap<String, Date> map = new HashMap<>();
map.put("Stallone", df.parse("MAY 1 2012"));
map.put("Stallone2", df.parse("JUNE 1 2012"));
map.put("Stallone3", df.parse("JULY 1 2012"));
map.put("Schwarzenegger", df.parse("AUGUST 1 2012"));
map.put("Schwarzenegger2", df.parse("SEPTEMBER 1 2012"));
map.put("Schwarzenegger3", df.parse("MAY 1 2012"));
map.put("Willis", df.parse("JUNE 1 2012"));
map.put("Willis2", df.parse("JUNE 1 2012"));
map.put("Willis3", df.parse("JUNE 1 2012"));
map.put("Stallone4", df.parse("JUNE 1 2012"));
return map;
}
public static void removeAllSummerPeople(HashMap<String, Date> map) {
HashMap<String, Date> copy = new HashMap<>(map);
for (String key : copy.keySet()) {
Date date = copy.get(key);
int month = date.getMonth() + 1;
if (month == 6 || month == 7 || month == 8) {
map.remove(key);
}
}
}
public static void main(String[] args) {
}
}