Unable to process the last requirement.

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Dear CodeGym Members, Good Morning. I am unable to complete this task and need your help for the same. The last requirement say "The removeAllSummerPeople() method should remove from the map all people born in the summer.". This is the logic which I created however it's not working.

public static void removeAllSummerPeople(HashMap<String, Date> map) throws ParseException {
        DateFormat df = new SimpleDateFormat("MM", Locale.ENGLISH);
        Iterator iterator = map.entrySet().iterator();

        while (iterator.hasNext()) {
            Map.Entry<String,Date> entry = (Map.Entry)iterator.next();

            if( Integer.parseInt(df.format(entry.getValue()))>=05 && Integer.parseInt(df.format(entry.getValue()))<=07)
                map.remove(entry.getKey());

        }
    }

Would it be possible to please explain what mistake I am doing? Thanks in advance for your help and support. Regards, Sanjay Chauhan

Create a Map<String, Date> and add ten entries that represent (last name, birth date) pairs.
Remove from the map all people born in the summer.
Hint: At CodeGym, summer lasts from June 1 to August 31.

Requirements:

The program should not display text on the screen.
The program should not read values from the keyboard.
The createMap() method must create and return a HashMap that has (String, Date) elements and contains 10 entries.
The removeAllSummerPeople() method should remove from the map all people born in the summer.

package com.codegym.task.task08.task0816; import java.text.DateFormat; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.*; import java.util.logging.SimpleFormatter; /* Kind Emma and the summer holidays */ 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<String, Date>(); map.put("Stallone1", df.parse("JUNE 1 1980")); map.put("Stallone2", df.parse("JUNE 1 1980")); map.put("Stallone3", df.parse("JUNE 1 1980")); map.put("Stallone4", df.parse("JUNE 1 1980")); map.put("Stallone5", df.parse("JUNE 1 1980")); map.put("Stallone6", df.parse("JUNE 1 1980")); map.put("Stallone7", df.parse("JUNE 1 1980")); map.put("Stallone8", df.parse("JUNE 1 1980")); map.put("Stallone9", df.parse("JUNE 1 1980")); map.put("Stallone10", df.parse("JUNE 1 1980")); return map; } public static void removeAllSummerPeople(HashMap<String, Date> map) throws ParseException { DateFormat df = new SimpleDateFormat("MM", Locale.ENGLISH); Iterator iterator = map.entrySet().iterator(); while (iterator.hasNext()) { Map.Entry<String,Date> entry = (Map.Entry)iterator.next(); if( Integer.parseInt(df.format(entry.getValue()))>=05 && Integer.parseInt(df.format(entry.getValue()))<=07) map.remove(entry.getKey()); } } public static void main(String[] args) { } }

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Skynet

Level 40 , USA

12 February 2020, 09:50

solution

Try this:

public static void removeAllSummerPeople(HashMap<String, Date> map) {
      map.entrySet().removeIf(pair -> pair.getValue().getMonth() > 5 & pair.getValue().getMonth() < 9);
}

Sanjay Chauhan

Level 28 , Delhi, India

12 February 2020, 07:14

I got the it after 25th attempt. :) I was using the wrong month number. Jan is starting from 01 not from 00.

public static void removeAllSummerPeople(HashMap<String, Date> map) throws ParseException {
       DateFormat df = new SimpleDateFormat("MM", Locale.ENGLISH);
        Iterator iterator = map.entrySet().iterator();
        ArrayList<String> list = new ArrayList<String>();

        while (iterator.hasNext()) {
            Map.Entry<String,Date> entry = (Map.Entry)iterator.next();

            //STEP 4: Method should remove from the all map all the people born in the summer.
            if( Integer.parseInt(df.format(entry.getValue()))>=6 && Integer.parseInt(df.format(entry.getValue()))<=8)
                list.add(entry.getKey());
        }

        for(String l : list){
           // System.out.println(l);
            map.remove(l);
        }
    }

Sanjay Chauhan

Level 28 , Delhi, India

12 February 2020, 02:48

Update - Code is working fine in IJ now. However still not able to pass the task. I have updated the removeAllSummmerPeople() :(

public static void removeAllSummerPeople(HashMap<String, Date> map) throws ParseException {
       DateFormat df = new SimpleDateFormat("MM", Locale.ENGLISH);
        Iterator iterator = map.entrySet().iterator();
        ArrayList<String> list = new ArrayList<String>();

        while (iterator.hasNext()) {
            Map.Entry<String,Date> entry = (Map.Entry)iterator.next();

            //STEP 4: Method should remove from the all map all the people born in the summer.
            if( Integer.parseInt(df.format(entry.getValue()))>=05 && Integer.parseInt(df.format(entry.getValue()))<=07)
                list.add(entry.getKey());
        }

        for(String l : list){
          //  System.out.println(l);
            map.remove(l);
        }
    }