I want to store values and retrieve them from a Java HashMap.
This is what I have so far:
public void processHashMap()
{
HashMap hm = new HashMap();
hm.put(1,"godric gryfindor");
hm.put(2,"helga hufflepuff");
hm.put(3,"rowena ravenclaw");
hm.put(4,"salazaar slytherin");
}
I want to retrieve all Keys and Values from the HashMap as a Java Collection or utility set (for example LinkedList
).
I know I can get the value if I know the key, like this:
hm.get(1);
Is there a way to retrieve key values as a list?
Java Hashmap key value example:
public void processHashMap() {
//add keys->value pairs to a hashmap:
HashMap hm = new HashMap();
hm.put(1, "godric gryfindor");
hm.put(2, "helga hufflepuff");
hm.put(3, "rowena ravenclaw");
hm.put(4, "salazaar slytherin");
//Then get data back out of it:
LinkedList ll = new LinkedList();
Iterator itr = hm.keySet().iterator();
while(itr.hasNext()) {
String key = itr.next();
ll.add(key);
}
System.out.print(ll); //The key list will be printed.
}