java - 一个键没有插入到哈希图中

Question

我有一个带有一个数字和一个名称的哈希图。它具有预先输入的值，我也想从用户那里获取输入。然后我想根据数字对其进行排序。

import java.util.HashMap;
import java.util.Set;
import java.util.Map;
import java.util.TreeMap;
import java.util.Iterator;
import java.util.Scanner;

class CFG{

    public static void main(String[] args) {
        HashMap<String,String> hm = new HashMap<String,String>();
        Scanner in = new Scanner(System.in);
        hm.put("342","Shiran");
        hm.put("448","Hasini");
        hm.put("398","Chanchala");
        hm.put("399","Priyankara ");
        hm.put("350","Mayuri");
        hm.put("321","Sameera");
        hm.put("299","Supun");
        hm.put("378","Supuni");
        hm.put("384","Kavindu");
        hm.put("440","Nadeeka");



        System.out.println("current players and times -");
        printMap(hm);

        System.out.println("-------------------- \n");
        System.out.println("Do you want to add more ?");
        System.out.println("If yes press 1 : ");
        Integer d = in.nextInt();
        if(d ==1){

                System.out.print("Insert a number: ");
                String a = in.nextLine();
                in.nextLine();// This consumes the \n character)
                System.out.print("Insert name: ");
                String b = in.nextLine();
                hm.put(a,b);

        }

        Map<String, String> treeMap = new TreeMap<String, String>(hm);
        printMap(treeMap);
    }//main

    public static void printMap(Map<String,String> map) {
        Set s = map.entrySet();
        Iterator it = s.iterator();
        while ( it.hasNext() ) {
            Map.Entry entry = (Map.Entry) it.next();
            String key = (String) entry.getKey();
            String value = (String) entry.getValue();
            System.out.println(key + " => " + value);
        }

    }

}

当用户输入“100”和“John”（例如）时，输出如下所示。如您所见，名称已输入，但数字未输入。我怎样才能解决这个问题 ？

 => john
299 => Supun
321 => Sameera
342 => Shiran
350 => Mayuri
378 => Supuni
384 => Kavindu
398 => Chanchala
399 => Priyankara 
440 => Nadeeka
448 => Hasini

标签： javasortinghashmaptreemap