How to split a string in Java -


i have string, "004-034556", want split 2 strings:

string1=004 string2=034556

that means first string contain characters before '-', , second string contain characters after '-'. want check if string has '-' in it. if not, throw exception. how can this?

just use appropriate method: string#split().

string string = "004-034556"; string[] parts = string.split("-"); string part1 = parts[0]; // 004 string part2 = parts[1]; // 034556

note takes regular expression, remember escape special characters if necessary.

there 12 characters special meanings: backslash \, caret ^, dollar sign $, period or dot ., vertical bar or pipe symbol |, question mark ?, asterisk or star *, plus sign +, opening parenthesis (, closing parenthesis ), , opening square bracket [, opening curly brace {, these special characters called "metacharacters".

so, if want split on e.g. period/dot . means "any character" in regex, use either backslash \ escape individual special character split("\\."), or use character class [] represent literal character(s) split("[.]"), or use pattern#quote() escape entire string split(pattern.quote(".")).

string[] parts = string.split(pattern.quote(".")); // split on period.

to test beforehand if string contains character(s), use string#contains().

if (string.contains("-")) {     // split it. } else {     throw new illegalargumentexception("string " + string + " not contain -"); }

note, not take regular expression. that, use string#matches() instead.

if you'd retain split character in resulting parts, make use of positive lookaround. in case want have split character end in left hand side, use positive lookbehind prefixing ?<= group on pattern.

string string = "004-034556"; string[] parts = string.split("(?<=-)"); string part1 = parts[0]; // 004- string part2 = parts[1]; // 034556

in case want have split character end in right hand side, use positive lookahead prefixing ?= group on pattern.

string string = "004-034556"; string[] parts = string.split("(?=-)"); string part1 = parts[0]; // 004 string part2 = parts[1]; // -034556

if you'd limit number of resulting parts, can supply desired number 2nd argument of split() method. 

string string = "004-034556-42"; string[] parts = string.split("-", 2); string part1 = parts[0]; // 004 string part2 = parts[1]; // 034556-42

Comments

Post a Comment

Popular posts from this blog

Is there a better way to structure post methods in Class Based Views -

i'm using class based views in django , never specify url in ajax calls , omit action parameter in form because know these requests go through post method of class based view. notice view - profile page make many requests depending on user updating on page - post method become convoluted , if/else mess example: def post(self, request, *args, **kwargs): # handle user changing available date if request.post.get('availabledate') != none: self.updateavailabledate(request) return jsonresponse({'result':'success'}) if request.post.get('newprojectname') != none: creative_user = creativeuserprofile.objects.get(id = request.user.id) project = project.create_project(creative_user, request.post['newprojectname']) project.save() return jsonresponse({'projectid': project.id }) if request.post.get('projectimage') != none , request.files['file']: proj...
Read more

What is happening when Matlab is starting a "parallel pool"? -

running parallel cpu processes in matlab starts command parpool() according documentation , function: [creates] special job on pool of workers, , [connects] matlab client parallel pool. this function takes bit of time execute, on order of 30 seconds. in other multi-cpu paradigms openmp, parallel execution seems totally transparent -- i've never noticed behavior analogous matlab (granted i'm not experienced parallel programming). so, happening between time parpool() called , when finishes executing? takes long? parallel computing toolbox enables run matlab code in parallel using several different paradigms (e.g. jobs , tasks, parfor , spmd , parfeval , batch processing), , run either locally (parallelised across cores in local machine) or remotely (parallelised across machines in cluster - either 1 own, or 1 in cloud). in of these cases, code run on matlab workers , copies of matlab without interactive desktop. if you're intending run on remo...
Read more

php - Cannot override Laravel Spark authentication with own implementation -

during login process of laravel spark need request token of remote api. api stores exact same users , passwords laravel spark application. therefore need username , non hashed password of user during authentication process. i thought overriding authenticated method solution problem. in routes/web.php override post /login endpoint , pointing endpoint own logincontroller: <?php namespace app\http\controllers\auth; use illuminate\support\facades\log; use illuminate\http\request; use laravel\spark\http\controllers\auth\logincontroller sparklogincontroller; class logincontroller extends sparklogincontroller { /** * create new login controller instance. * * @return void */ public function __construct() { parent::__construct(); } /** * handle successful authentication attempt. * * @param request $request * @param \illuminate\contracts\auth\authenticatable $user * @return response */ public fu...
Read more