question about Iterator remove method

[rick collette]

Hi, guys:

I want to remove several items from a collection using Iterator's remove method,
but I got UnsupportedOperationException. Is there a way to solve thos problem?

thanks

[Jim Yingst]

What kind of collection are you using here? How did you obtain it? Whether or not remove() is supported is determined by how & where you got the collection - usually, if you consult the docs for the method or constructor used to create or access the collection, it will tell you if remove() is supported (as well as other methods). As an example, for a newly-created ArrayList or LinkedList, remove is supported by default. But if you wrap the list using Collections.unmodifiableList(), or if you have an array and you convert it to a list with Arrays.asList(), then remove() is not supported. So, what alternatives do you have? It's hard to say - we'd really need to know more about the collection you're using, and what you're trying to do.
[ January 02, 2005: Message edited by: Jim Yingst ]

[Ernest Friedman-Hill]

Remember that Iterator is an interface, and there are many different implementations within the Java APIs. Each implementation can choose whether or not to implement remove(). If you're getting that exception, then the implementation used in your particular situation doesn't support remove(). The only thing you can really do is to use a different collection class, one whose iterator does support remove().

[rick collette]

thanks guys,

I have an array and I convert it to a list using Arrays.asList(), I guess thats why remove() is not supported. I guess I really need to transform that
array into a collection that supports remove method? You guys' posts are very helpful.

[Ernest Friedman-Hill]

Although it's not the most efficient way to do things, you could say

List myCollection = new ArrayList(Arrays.asList(myArray));