removing enemy and bullet in collision java -

-

this question has answer here:

i making simple 2d game in java. have created controller class , created linked lists zombies(enemies) , bullets. in gamestate class trying use each loops loop through linked lists , detect if there collision bullet , zombie. way laid out below in code example, enemy can removed game, if try remove bullet well, game crashes. wondering if ideas on how can remove both entities after collision occurs.

this error when bullet collides enemy

exception in thread "thread-1" java.util.concurrentmodificationexception @ java.util.linkedlist$listitr.checkforcomodification(unknown source) @ java.util.linkedlist$listitr.next(unknown source) @ android.game.gamestate.update(gamestate.java:71) @ android.game.game.update(game.java:121) @ android.game.game.run(game.java:101) @ java.lang.thread.run(unknown source)

in gamestate class:

for(zombie zombie : c.z)     {         if(player.getx() > zombie.getx()){             zombie.setx(zombie.getx() + 1);         }          if(player.getx() < zombie.getx()){             zombie.setx(zombie.getx() - 1);         }          if(player.gety() > zombie.gety()){             zombie.sety(zombie.gety() + 1);         }          if(player.gety() < zombie.gety()){             zombie.sety(zombie.gety() - 1);         }          if(player.getbounds().intersects(zombie.getbounds())){              kills ++;             c.removezombie(zombie);             system.out.println("kills" + kills);          }          for(bullet bullet : c.b){             if(zombie.getbounds().intersects(bullet.getbounds())){                 //c.removebullet(bullet);                 c.removezombie(zombie);                 kills++;                  system.out.println("kills" + kills);                     }          }      }

controller class:

public class controller {  linkedlist<bullet> b = new linkedlist<bullet>(); linkedlist<zombie> z = new linkedlist<zombie>();  bullet tempbullet; zombie tempzombie;  public controller(){     addzombie(new zombie (200,600));     addzombie(new zombie (400,650)); }  public void tick(){     for(int = 0; i<b.size(); i++){         tempbullet = b.get(i);          tempbullet.tick();     }      for(int = 0; i<z.size(); i++){         tempzombie = z.get(i);          tempzombie.update();     }   }  public void draw(graphics g){     for(int = 0; < b.size(); i++){         tempbullet = b.get(i);          tempbullet.draw(g);     }      for(int = 0; < z.size(); i++){         tempzombie = z.get(i);          tempzombie.render(g);     }  }  public void addbullet(bullet block){     b.add(block); }  public void removebullet(bullet block){     b.remove(block); }  public void addzombie(zombie block){     z.add(block); }  public void removezombie(zombie block){     z.remove(block); } }

use iterator go through list, , use remove() method remove current element collection:

for(iterator<zombie> = c.z.iterator(); it.hasnext(); ) {     zombie zombie = it.next();     if (collisionwithbullet)         it.remove(); }

Comments

Post a Comment

Popular posts from this blog

java - Suppress Jboss version details from HTTP error response -

-
my jboss verson jboss eap 6.3 when kind of error response sent jboss, adds server information response. following sample row response: http/1.1 400 bad request server: apache-coyote/1.1 content-type: text/html;charset=utf-8 content-length: 2391 date: tue, 19 jul 2016 09:30:46 gmt connection: close jboss web/7.4.8.final-redhat-4 - jbweb000064: error report jbweb000065: http status 400 - org.codehaus.jackson.map.jsonmappingexception: can not construct instance of mybean.type string value 'xyz': value not 1 of declared enum instance names @ [source: org.jboss.resteasy.core.interception.messagebodyreadercontextimpl$inputstreamwrapper@5e421c2b; line: 14, column: 26] (through reference chain: requestargs["request"]) jbweb000309: type jbweb000067: status report jbweb000068: message org.codehaus.jackson.map.jsonmappingexception: can not construct instance of mybean.type string value 'xyz': value not 1 of declared enum instance names @ [source: org.jboss...
Read more

gridview - Yii2 DataPorivider $totalSum for a column -

-
i have order , ordersearch models. in order list (actionindex) gridview there filtering , sorting. on of columns in order order_total (sum of products in order). i need implement sum of order_total in gridview. if manually counting activedataprovider->getmodels() array_map spend 3 seconds 3000 orders (localhost). don't want miss time. i see 2 ways make faster: create cache every filter , update lifetime (horrible) the interesting can right in ordersearch->search() method $query method. don't understand how can pass in controller. example of code 2nd way: class ordersearch extends order { public $totalsum; public function search($params) { $query = order::find(); $dataprovider = new activedataprovider([ 'query' => $query, ]); $this->load($params); $this->totalsum = $query->sum('order_total'); // works fast return $dataprovider; } } after i...
Read more

Sass watch command compiles .scss files before full sftp upload -

-
i use winscp download , edit .scss files , sass on linux (on server) compile them .css . after saving file, use: sass scss/style.scss css/style.css , replaces css file compiled sccs. the problem i want skip part return command line after editing scss file, sake of automation , saving time. but, if use watch command: sass --watch scss/style.scss:css/style.css synchronize 2 files, alerts nonexistent css errors pop up: change detected to: scss/style.scss error scss/style.scss (line 232: invalid css after "...ht: bold; line-": expected "{", "") note that when file uploads quicker usual (sometimes happens) watch command job, no errors. this because, when file upload takes time, sass compiles scss file (on server) before uploaded remote folder. thus, compiles part of file, resulting in css errors. is there way set timer watch command waits few seconds after detects changes , before compiling? any other way overcome is, of course, ...
Read more