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Suma
10 Jul 2009, 5:14 AM
Hi,
I want to convert an HashMap<int, Class> to List<Class>. Kindly help me how to do this.

Pandaman
10 Jul 2009, 5:34 AM
I'm assuming that you want to get the collection of values from the HashMap.

Let's say your HashMap<Integer, Class> is called hashMap.

Most implementations of List have a constructor that takes in a collection. You can get a collection of the values from the values() method. To answer your question exactly using ArrayList:
List<Class> listOfClasses = new ArrayList<Class>(hashMap.values());

In the future you may want to ask basic java questions in a forum dedicated to java. You could also just look at the Java API documentation and figure it out yourself :-)
http://java.sun.com/javase/6/docs/api/ if you use Java 1.6

Pandaman
10 Jul 2009, 5:39 AM
By the way, why do you have a HashMap of int to Class? Wouldn't it be more efficient to use an ArrayList<Class> instead where the index acts like the key?

Suma
10 Jul 2009, 5:43 AM
Thank you for your help. But i'm facing problem in retrieving the values from list, i'm not able to cast it to the Class.

Pandaman
10 Jul 2009, 5:55 AM
I'm not sure what you mean.

I would ask you to post some sample code, but I might get yelled at by the moderator for continuing this non-GXT related conversation :s. Try asking on a Java forum (like Sun's: http://forums.sun.com/index.jspa) where it may be more appropriate.

sven
10 Jul 2009, 5:56 AM
but I might get yelled at by the moderator for continuing this non-GXT related conversation

Why should you? There is no problem with this.

Pandaman
10 Jul 2009, 6:15 AM
Because this is a forum for GXT help, not Java help?