How do you put the cat object in the map??

Question about the task

Under discussion

// put cats in HashMap
       for (int i = 0; i < cats.length; i++)
       {
           Cat cat[i] = new Cat();
           catMap.put(cats[i], cat[i]);
       }

I know you can't do this but this is where my thinking is. Do you need to create a new Cat each time and put it in the hashmap. What do need to put for the second argument of put. Thanks in advance

There is a Cat class with a String name.
Create a HashMap<String, Cat>.
Add 10 cats to the collection. The cat's name should be used as the key.
Display the result on the screen, each element on a new line.

Requirements:

The program should not read values from the keyboard.
In the addCatsToMap() method, declare a HashMap variable with (String, Cat) pairs and immediately initialize it.
The addCatsToMap() method should add all cats in the String[] cats array to the collection in accordance with the task conditions.
The program should display the contents of the collection on the screen, each pair on a new line and with the key and value separated by a hyphen.

package com.codegym.task.task08.task0803; import java.util.HashMap; import java.util.Map; /* HashMap of cats */ public class Solution { public static void main(String[] args) throws Exception { String[] cats = new String[]{"Tiger", "Missy", "Smokey", "Marmalade", "Oscar", "Snowball", "Boss", "Smudge", "Max", "Simba"}; HashMap<String, Cat> map = addCatsToMap(cats); for (Map.Entry<String, Cat> pair : map.entrySet()) { System.out.println(pair.getKey() + " - " + pair.getValue()); } } public static HashMap<String, Cat> addCatsToMap(String[] cats) { //write your code here // initialize hashmap HashMap<String, Cat> catMap = new HashMap<String, Cat>(); // put cats in HashMap for (int i = 0; i < cats.length; i++) { Cat cat = new Cat(); catMap.put(cats[i], cat); } // display contents of HashMap // for (Map.Entry<String, Cat> cat : catMap.entrySet()) // { // String key = cat.getKey(); // Cat value = cat.getValue(); // System.out.println(key + " - " + value); // } } public static class Cat { String name; public Cat(String name) { this.name = name; } @Override public String toString() { return name != null ? name.toUpperCase() : null; } } }

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Gellert Varga

Level 23 , Szekesfehervar, Hungary

7 February 2021, 21:07

You wrote this:

// put cats in HashMap
        for (int i = 0; i < cats.length; i++)
        {
            Cat cat = new Cat();
            catMap.put(cats[i], cat);
        }

and i think it's quite good! With only one mistake: you didn't send the actual string to the Cat-constructor: see line 51, and see the requirements: "The cat's name should be used as the key".

Gellert Varga

Level 23 , Szekesfehervar, Hungary

7 February 2021, 21:14

or in other words: "The newly created cat's name should be equal to the key".