doubt on HashMap

[Seetharaman Venkatasamy]

Hi All,

i have 2 questions

1) what is the difference between ArrayList and LinkedList

2) how to get the key value from HashMap

please can any one tell me the solution...

Thanks & Regards,
seetharaman.v

[Katrina Owen]

Hi there,

For LinkedList vs ArrayList, could you be more specific? Are you asking about performance differences between the two data structures?

For the HashMap, I'd suggest that you take a look at the API, try to apply what you find there in an example, and if you get stuck, show us what you've got, and we'll help you figure out what went wrong.

[Seetharaman Venkatasamy]

Hi Katrina,

well, i looked the api... my question is how you will get the keys from hashmap..

second thing) what is the performance (datastructure) difference between ArrayList and LinkedList

[marc weber]

Originally posted by seetharaman venkatasamy:
...well, i looked the api... my question is how you will get the keys from hashmap...

Didn't you see the method keySet()?

For differences among Lists, see Choosing between Lists from Eckel's Thinking in Java.

[Seetharaman Venkatasamy]

Thanks a lot katrina and marc