java - return a syncrhonized value from a syncrhonized block -



java - return a syncrhonized value from a syncrhonized block -

if have map of objects , each threads can go within each buckets concurrently,resulting block like

syncrhonized(values.get(objecttolock)){ int sum = 0; for(int = 0; i< new random().nextint(1000)+2; i++) sum+=i; homecoming sum; }

update

syncrhonized(values.get(objecttolock)){ int sum = 0; for(int = 0; i< new random().nextint(1000)+2; i++) sum+=i; for(int = 0; < 10; i++) for( int j = 0; j < 10 ; j++) system.out.println(*); homecoming sum; }

in piece of code, each thread can interfere between them resulting in sum distorted?

no, sum local variable. each thread have own copy.

declaring outside of synchronized block doesn't create less of local variable, makes scope larger.

java multithreading

Comments

Post a Comment

Popular posts from this blog

Php operator `break` doesn't stop while -

Php operator `break` doesn't stop while - have weird issue, break doesn't break while loop , maintain rotating. logically should break cycle , set output while ($c++ != 5) { // here curl request, doesn't relevant have removed preg_match("!<.*?>(\s*)[^<>]*?{$to}<!", $resp, $result) ; // echo 'cnt = ' .count($result).'<br>'; if(!count($result)) { $amount = 0; echo 'sleep called'; sleep(4); exit; continue; } else { $amount = trim(@$result[1]); $amount = round($amount + $amount * $exchange_ratio, $precision); echo 'break happen<br>'; break; } } so output cnt = 2 break happen cnt = 0 sleep called so skipped break , maintain rotating. how so? edit works fine on localhost issue php version? ...
Read more

ubuntu - Bash Script to Check That Files Are Being Created -

ubuntu - Bash Script to Check That Files Are Being Created - we have amazon ec2 instance upload output our security cameras. every , then, cameras have issue, stop uploaded, , need rebooted. easy way determine seeing if files not beingness created. problem creates lots , lots of files. if utilize find -ctime, takes long time script run. there faster way check see if files have been created since yesterday? need capture result, (yes there files, or not there not,) , email message, nice have didn't take half hr run. #!/bin/bash find /vol/security_ftp/west -ctime -1 find /vol/security_ftp/backentrance -ctime -1 find /vol/security_ftp/boardroomdoor -ctime -1 find /vol/security_ftp/mainentrance -ctime -1 find /vol/security_ftp/north -ctime -1 find /vol/security_ftp/south -ctime -1 using find natural solution, if must avoid it, can see newest file in directory using ls , sorting output according ctime, eg. ls /vol/security_ftp/west -clt | head --lines=1 ...
Read more

vim: Search & replace -

vim: Search & replace - i searching easy way search , replace things in vim "workaround" refactoring. on other stackoverflow-question found snippet of code: nnoremap gr gd:%s/<c-r>///gc<left><left><left> i thought gd selects current word under cursor in whole document , %s search , replaces matches after typed replace pattern. gc stands globally confirmation?! however: not work expected. illustration in python class of mine can easy rename occurencies of self in whole file not work on method identifieres or field identifieres length of one. def __init__(self): self.test = [] self.a = [] ... so self changed using snippet, doing gr on field a not work. how can work easy search , replace on 1 file? any tips on intelligent refactoring appreciated. after hours of searching found plugins , workarounds work c files, need @ to the lowest degree java, python , php compatibility. thanks every reply :) update: found...
Read more