Adding element to HashTable of Stack objects

Question

I have a HashTable of Stack objects:

Hashtable<String, Stack<Integer>> ht;

I want the data structure to be something like this:

"foo" => [3,6,12]
"bar" => [5,8,1]

"foo" and "bar" are keys and the two [x,y,z]s are the stacks.

How do I do something like push an Integer onto the stack in the hash table with key "a"?

Many thanks.

ht.get("a").push(myInteger), but it would had been better if you had tried this by yourself in your code — morgano, Jul 19 '13 at 21:03
hmm.. maybe I should close.. this was too obvious to benefit others?! Many thanks. — ale, Jul 19 '13 at 21:03

score 2 · Answer 1 · answered Jul 19 '13 at 21:03

2

Have you tried

yourHashTable.get("a").push(new Integer(2));

answered Jul 19 '13 at 21:03

Zavior

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score 2 · Accepted Answer · edited May 23 '17 at 11:57

2

You can try something like this :

if(ht.containsKey("a")) {
  ht.get("a").push(0); // push some Integer
}
else {
  Stack<Integer> stack = new Stack<Integer>();
  stack.push(0); // push some integer
  ht.put("a",stack);
}

You need to use push() of Stack.

P.S: Move to HashMap instead of HashTable if you can.

Read When should I use a Hashtable versus a HashMap?

edited May 23 '17 at 11:57

Community

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answered Jul 19 '13 at 21:03

AllTooSir

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score 2 · Answer 3 · answered Jul 19 '13 at 21:05

2

In order to modify a given stack, retrieve a reference to it and and add the new integer.

myHashTable.get("a").push(new Integer(7));

answered Jul 19 '13 at 21:05

Shamim Hafiz - MSFT

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score 0 · Answer 4 · answered Jul 19 '13 at 21:06

0

Stack<Integer> stack = hashtable.get(key);
stack.push(myint);
hashtable.put(key, stack);

Something like this, maybe :)?

answered Jul 19 '13 at 21:06

Fly

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Adding element to HashTable of Stack objects

4 Answers4