Single Integer in HashMap ?

Is it possible to put just a single Integer into a hashmap?
I want to set a number (as "security" key) for something.

e.g.:

Code:

Integer number = 1234;
 
// Missing HashMap stuff here
 
if (commandLabel.equalsIgnoreCase("newkey")
{
singleinteger.put(number);
}
 
 
if (message.equals(number))
{
singleinteger.remove(number);
}

 

I don't understand your question. Do you want a HashMap<Object, Integer>, a HashMap<Integer, Object>, or don't you actually need a map, but a set?
btw: This might help: http://en.wikipedia.org/wiki/Java_collections_framework

 

Do I need a Hashmap? Not sure about that. That's why I'm asking.

I just want to store a given number.
If I type the stored number in the chat it will trigger something.
Also it will remove the stored number.

 

most people want an hashmap whit key the player or mostly its name, see my sign, and as value what they want , so:
Map<String,Integer>

 

If you intend to have more than one number stored at a time you should use a Set<Integer> to store them, and can use .contains(int) to find whether a number is stored and .remove(int) to remove a number from the set.
If you however only have one number i suggest a simple int which you set to -1 when it is used.

 

Create a HashMap

Code:

Map<String, Integer> security = new HashMap<String, Integer>();

Add a entry to the HashMap

Code:

security.put("Player Name", Securiry Key);

Remove an entry from the HashMap

Code:

security.remove("Player Name");

 

It's a single number which gets randomly generated and I want to store it.

Code:

Integer random = 1+object.nextInt(100);

Now if I type exactly this message it gets removed and can't be used a second time.

Code:

if (message.equals(storednumber)

 

Use a set:

Code:

Set<Integer> a = new HashSet<Integer>();

Code:

Integer b = Integer.parseInt(message); // Put in try/catch
 
if (a.contains(b)) {
    a.remove(b);
    // stuff
}

 

As suggested, use a Set or an alternative would be ArrayList.

 

HON95
Thanks for the example.
Got it now.

 

ItsHarry A ArrayList is bad for storing Integers, cause it has the function remove(int index) which will conflict with remove(Object o).

 

Another Problem (related to Set):

I want to parse an Integer from Command (That works).

Code:

Set<Integer> rewards = new HashSet<Integer>();

Code:

        if (args.length == 1) {
            try {
                Integer reward = Integer.parseInt(args[0]);
                rewards.add(reward);
            } catch (NumberFormatException nfe) {
            }
        }

Now how can I access the Integer from other methods?

Code:

public void onPlayerMove(PlayerMoveEvent event) {
    Player player = event.getPlayer();
    if (player.hasPermission("run.reward")) {
        run.economy.depositPlayer(player.getName(), HOW TO GET THE INT FROM THE SET "rewards" ?);

Or is there something which works without Set for this?

 

recon88
So you want each player to have a reward value or something ? Because then a hashmap would be useful with String (playername) and Integer.

Also, why are you using PlayerMoveEvent for rewards ??? Just make a task if you want to delay it...

 

That was just a fast written example =)

For some reasons it doesn't work:

Code:

HashMap<Player, Integer> rewards = new HashMap<Player, Integer>();

On Command

Code:

rewards.put(player.getPlayer(), reward);

On Event

Code:

run.economy.depositPlayer(player.getName(), rewards.get(player));
rewards.remove(player);

- I want to execute a command. Like "/run 120".
- Now I want to store the 120.
- After someone triggers the event he/she will get the 120 rewarded.

 

First, use player names.

Then, what you're showing should work tough, there could be another problem there... try some debug messages, print player name, value, retrieved value from hashmap, etc.

 

What's wrong with that? If I trigger the event I'll get the reward.
If someone else triggers it the console throws an exception:

HashMap

Code:

HashMap<Player, Integer> rewards = new HashMap<Player, Integer>();

On Command

Code:

rewards.put(player.getPlayer(), reward);

On Event

Code:

Player player = event.getPlayer();
Integer reward = rewards.get(player);
run.economy.depositPlayer(player.getName(), reward);  (LINE 104)
rewards.remove(player);

Exception

Code:

[SEVERE] Could not pass event PlayerMoveEvent to Run
org.bukkit.event.EventException
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:304)
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:459)
    at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:786)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:764)
    at net.minecraft.server.Packet3Chat.handle(Packet3Chat.java:34)
    at net.minecraft.server.NetworkManager.b(NetworkManager.java:229)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:113)
    at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:78)
    at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:567)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:459)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.NullPointerException
    at com.recon.Run.Run.onPlayerMove(Run.java:104)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:302)

Btw, if I use player names it also throws exceptions.

nvm... I used a static string instead of player now.

HashMap

Code:

HashMap<String, Integer> rewards = new HashMap<String, Integer>();

On Command

Code:

String thereward = "rew";
 
  Integer reward = Integer.parseInt(args[0]);
  rewards.put(thereward, reward);

On Event

Code:

Player player = event.getPlayer();
String thereward = "rew";
Integer reward = rewards.get(thereward);
 
run.economy.depositPlayer(player.getName(), reward);
rewards.remove(thereward);

Works now with that code.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

what is: com.recon.Run.Run.onPlayerMove(Run.java:104)
give us that row

 

See "OnEvent" i wrote down "(LINE 104)" there.
But as I said i got that fixed with a static String. So that's OK now.

 

that line is the ccause of your lastest exception, so theres something wrong there

 

That makes no sense what you are saying.

As I said I marked Line 104. But there was no mistake in it.
Also I fixed it with a static string (as I already said).

So: Already solved

 

recon88 your fail was here:
Integer reward = rewards.get(player);
That's the only thing that could give a NPE at line 104. And that means the list rewards didn't have the entry player. Why not? Cause the list stores the object type String, not Player... so the fix would have been to relpace it with:
Integer reward = rewards.get(player.getName());

 

V10lator
Oh ok. Thanks for that.
Well. It also works with that string now.. But I'll use this one if I need it again =)