Sorting Components

[John]

I need to store hundreds of Components (a real mix of subclasses) in an
array/list, and need to be able to search the array for the presence of
a given Component . I therefore need to sort the array by some key which
is unique among components to avoid wasting lots of time doing equals()
comparisons.

At the moment I am considering sorting by Object.hashCode() and dealing
with conflicts by using equals() comparisons.

Does anyone have a better suggestion for doing this?

 

[Matt Humphrey]

I need to store hundreds of Components (a real mix of subclasses) in an
array/list, and need to be able to search the array for the presence of
a given Component . I therefore need to sort the array by some key which
is unique among components to avoid wasting lots of time doing equals()
comparisons.

By what key are you searching for them? If you're only testing for existence
in the list / set, use a HashMap (e.g. searching by object reference). If
you're trying to find one based on other key values (name, etc) use one or
more TreeMap as indexes, each using a different key.

At the moment I am considering sorting by Object.hashCode() and dealing
with conflicts by using equals() comparisons.

Does anyone have a better suggestion for doing this?

Cheers,
Matt Humphrey (e-mail address removed) http://www.iviz.com/

 

[Roedy Green]

I need to store hundreds of Components (a real mix of subclasses) in an
array/list, and need to be able to search the array for the presence of
a given Component . I therefore need to sort the array by some key which
is unique among components to avoid wasting lots of time doing equals()
comparisons.

Have a look at the source for Accumulate at
http://mindprod.com/products.html#ACCUMULATE

It extracts the keys from the HashMap and sorts them when needed.