Why doesn't my hashtable populate? Java

I'm trying to pre-populate a Hashtable from a different class called ZipCodes

Here's my ZipCodes class with some test data:

import java.util.Hashtable;

public class ZipCodes {
	final static Hashtable<String, String> zipCodesList
    = new Hashtable<String, String>();
	public static void main() {

		zipCodesList.put("00501", "NY218");
		zipCodesList.put("00544", "NY218");
		zipCodesList.put("00601", "XX499");
		zipCodesList.put("31036", "GA076");
		zipCodesList.put("31037", "ZZ560");
		zipCodesList.put("31038", "ZZ740");
	        return;
	}

}

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When I call upon ZipCodes in my code, it compiles fine, it just doesn't have data inside of it.

Here's what my call looks like:

Hashtable<String, String> zipCodesListing = ZipCodes.zipCodesList;
    	      cityName = zipCodesListing.get(cityCode);

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The actual part where it does a .get(cityCode) works when the hashtable is being declared and populated in my main code.  But all it's returning is null.
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Dale HarrisProfessional Services EngineerAsked:
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for_yanCommented:
Show how two pieces of your code actuall are comabined. when you execute the second snippet ?
Dale HarrisProfessional Services EngineerAuthor Commented:
Yes.  It's based on a button push.  The class that I posted called ZipCodes is a standalone class in it's entirety.  That's all it does.  All the rest of my code is in my main java file.
for_yanCommented:
This part will just execute, ppulate Hashatble and then exit

public static void main() {

		zipCodesList.put("00501", "NY218");
		zipCodesList.put("00544", "NY218");
		zipCodesList.put("00601", "XX499");
		zipCodesList.put("31036", "GA076");
		zipCodesList.put("31037", "ZZ560");
		zipCodesList.put("31038", "ZZ740");
	        return;
	}

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- so when would you have a chance to say this:

Hashtable<String, String> zipCodesListing = ZipCodes.zipCodesList;
                cityName = zipCodesListing.get(cityCode);
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for_yanCommented:
No you can't do that - this class will execute and go away together with your Hashtable


You shuld do something like that - all from when you push the button
ZipCodes.populate();
Hashtable<String, String> zipCodesListing = ZipCodes.zipCodesList;
                cityName = zipCodesListing.get(cityCode);




public static void populate() {

		zipCodesList.put("00501", "NY218");
		zipCodesList.put("00544", "NY218");
		zipCodesList.put("00601", "XX499");
		zipCodesList.put("31036", "GA076");
		zipCodesList.put("31037", "ZZ560");
		zipCodesList.put("31038", "ZZ740");
	        
	}

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for_yanCommented:
That should ber your class:

import java.util.Hashtable;

public class ZipCodes {
	final static Hashtable<String, String> zipCodesList
    = new Hashtable<String, String>();
	public static void populate() {

		zipCodesList.put("00501", "NY218");
		zipCodesList.put("00544", "NY218");
		zipCodesList.put("00601", "XX499");
		zipCodesList.put("31036", "GA076");
		zipCodesList.put("31037", "ZZ560");
		zipCodesList.put("31038", "ZZ740");
	        
	}

}
                                  

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and thats how it acn be used in another class:

ZipCodes.populate();
Hashtable<String, String> zipCodesListing = ZipCodes.zipCodesList;
                cityName = zipCodesListing.get(cityCode);

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Dale HarrisProfessional Services EngineerAuthor Commented:
That was it!  Thanks.  Now I understand what you mean.  It's creating the variable because it's above the method.  But it wasn't doing the rest of it because it was not being called.

Thanks again!
Dale HarrisProfessional Services EngineerAuthor Commented:
Great, fast, easy solution!
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