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Problem of Creating JTree with Hashtable ?

Posted on 2000-04-18
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Last Modified: 2008-03-06
hi,

Currently I'm facing a problem with the node order of the JTree generated from the Hashtable. The order in which objects are added to a Hashtable exhibit an unpredictable node order. It seems that there has no correlation to the manner in which the objects are stored in the Hashtable.

eg. the order to put a object into the Hashtable.

Hashtable ht = new Hashtable();
   ht.put("Page 1", page1Vector);
   ht.put("Page 2", page2Vector);

JTree jt = new JTree(ht);  

The node order of the JTree might be "Page 2" as a first node and "Page 1" as a second node which is not in the desired order.

Is there any way to solve the ordering problem or sorting the Hashtable ?

Hope to hear from you soon, thank you.
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Question by:andric
2 Comments
 
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Expert Comment

by:lyonst
ID: 2726407
Hi,

I'm not sure if this helps but it is an example of how to load a Hashtable form SUN - there dosn't appear to be a specific sort order but could you use the integer value to loop and read the values in the correct sequence?.


This example creates a hashtable of numbers. It uses the names of the numbers as keys:

          Hashtable numbers = new Hashtable();
          numbers.put("one", new Integer(1));
          numbers.put("two", new Integer(2));
          numbers.put("three", new Integer(3));
     

To retrieve a number, use the following code:

          Integer n = (Integer)numbers.get("two");
          if (n != null) {
              System.out.println("two = " + n);
          }

T.
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Accepted Solution

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ovidiucraciun earned 100 total points
ID: 2726544
>>The node order of the JTree might
>>be "Page 2" as a first node and "Page
>>1" as a second node which is not in
>>the desired order

That means you should insert like this
Hashtable ht = new Hashtable();
   ht.put("Page 2", page2Vector);
   ht.put("Page 1", page1Vector);



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