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General <strong>Java</strong> Questions IV<br />
(myfile.properties)<br />
6) When you're done, erase the original and rename your new one to original.zip.<br />
I believe that this may be the only way to do this, since there doesn't seem to be any<br />
random access in the ZIP file.<br />
--<br />
Kevin T. Smith<br />
Q: About the order of my elements in hastable...<br />
I save some data into hashtable.<br />
For example,<br />
hashtable.put ( "1", "one" );<br />
hashtable.put ( "2", "two" );<br />
hashtable.put ("3" , "three" );<br />
when I get back the element from hashtable using Enumeration class ,<br />
Enumeraton e = hashtable.keys();<br />
while ( e.hasMoreElements() ){<br />
Object k = e.nextElement();<br />
Object v = hashtable.get (k );<br />
}<br />
the default result is<br />
"3","three"<br />
"2", "two"<br />
"1", "one"<br />
here I want to get the data sorted as ascending. ( the order as I insert ) such as<br />
"1", "one"<br />
"2", "two"<br />
"3", "three"<br />
or is it possible to get the data from end of hashtable?<br />
Answer: When you insert elements into a Hashtable, they will not be stored in the<br />
order you insert them. They are stored in a way that makes it easy to find them by<br />
the key you specify.<br />
So, you must either use another data structure (e.g. Vector) or sort them after you<br />
retrieve them from the Hashtable (e.g. by using java.util.Collections, java.util.Arrays).<br />
--<br />
Marco Schmidt<br />
Q: What is better to use: array or vector?<br />
Just wondering as I am using Vectors to store large amounts of objects from 50 to<br />
4000 and each one has to be "looked at" every time paint is called...<br />
Just wondering if it would be better to use an array, list etc?<br />
Answer 1: Since the Vector method uses an array for storage but has extra steps<br />
involved in getting an element, use an array for fastest access.<br />
--<br />
WBB <strong>Java</strong> Cert mock exams http://www.lanw.com/java/javacert/<br />
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