oop - How abstraction is achieved using interfaces in java -


i know

abstraction process of hiding implementation details , showing functionality.

but using interfaces can not implement thing.we need implemented class develop applications.for example in java have list interface has sub classes linkedlist , arraylist.they provided code classes also.we able see code implemented code.can 1 give me example abstraction.

if give interface someone, can achieve abstraction.but example this?

hiding here means making client of code independent of underlying implementation.

interfaces specify what can do. implementations specify how it.

as how tos improve/change time, client (another piece of code) using interfaces continues work without modification. client still gets wants, in more efficient manner now.

abstraction style of programming aimed @ easing lives of programmers , consumers. has nothing hiding source code others. there other ways it.


Comments

Post a Comment

Popular posts from this blog

php - Submit Form Data without Reloading page -

i know question has been asked , answered bunch of times life of me can not solution work on code. believe if redo code, work properly, , in retrospect time i've spent on issue should have redone code...but beyond deadline , have working prototype up... can advise how update multiple forms on single page without reloading page? horrible @ php , complete noob js/jquery/ajax @ best. html/php in single file , believe causing me problems/is largest obstacle @ getting ajax form processing work. basically, want users to: select teams multiple dropdowns in form group 1 (league champs) , on update update db newly selected team without reloadding page. edit team scores per match , on score submit/update, update db new scores. for each requirement there multiple forms (1 each leagues, 1 each per match) have set class on each form id. everything works via php, form submission reloads page each time submitted , not ideal. i have tried ajax code here http://scotch.io/tutoria
Read more

linux - Rails running on virtual machine in Windows -

the reason why want switch ubuntu people said gems works better on linux on windows. i don't want macbook pro rails development since love windows , cannot stand lack of apps mac. moreover, people saying ubuntu "better" mac: http://www.reddit.com/r/ubuntu/comments/1bgj1s/are_there_advantages_of_ubuntu_over_os_x_for/ does virtual box work enough doesn't have lag @ all? using i7-3517u cpu 8gb memory. need program in environment lag-free , not sluggish. or there alternatives recommend? i unsure permission settings or complicated stuffs regarding terminal. i'll using terminal develop. i'm still quite new here development in linux. please kind me >< thanks. @holyxiaoxin pretty sure should asking on superuser instead. nevertheless, suggest install ubuntu in partition instead of running virtual machine. here's guide https://help.ubuntu.com/community/windowsdualboot also, yes. developing in virtual machine accurate, @ end experiment w
Read more

php - $params->set Array between square bracket -

i'm using k2 in joomla 3.3. i'm trying set params (items ids ) module k2_content item.php file. result must between brackets, like: ["96","68"] my code is: $query = "select * #__k2_items extra_fields_search = '$myautor' , catid !=1 " ; $db->setquery($query); $losautores = $db->loadobjectlist(); $result = array(); foreach ($losautores $key => $value) { $result[] = '" '.$value->id.' "'; } $string_version = implode(',', $result); $autoresfinal = '['.$string_version.']'; if test using print, looks ok. passing var pramas, 1064 error. $params->set('items', $autoresfinal); to test tried $autoresfinal = ["96","68"]; and works fine. idea why doesn't work? thank you. if assign ["x","y"] assigning an array . here transforming array in st
Read more