java - Bouncing Balls in ArrayList Need to Detect Collisions -

hi making bouncingball program balls bounce off walls , off each other. walls fine, collisions problem. storing balls in arraylist can move given number using each loop.

i have been unable implement collisions , have looked lot. closest can there lots of random collisions when there shouldn't be.

latest attempt: physics class detect collisions , balls run off screen..

public class physics {

public static boolean collision(bouncingball b, arraylist<bouncingball> list){     //boolean collide = false;     (int = 0; < list.size(); i++){        if(b.getxposition()== list.get(i).getxposition()){           return true;       }      }     return false; } 

the bounce method itself(in class balldemo):

                ball.draw();                 //above here code make balls , add arraylist             }              // make them bounce             boolean finished =  false;              while (!finished) {                 mycanvas.wait(50);                  (bouncingball ball: balls){                       if(physics.collision(ball, balls)){                         collisioncount(ball);                     }                        //if ball out of x bounds bounce                 else if(ball.getxposition()>=850 || ball.getxposition()<0){                         ball.collision();                       }                     //if ball out of y bounds bounce               else if(ball.getyposition()>=500 || ball.getyposition()<0){                         ball.ycollision();                      }                     ball.move();                     }                 }         } 

just note:i aware of loop having conflicts due comparing first ball have tried starting @ 1 , still doesn't work.

since comparing each ball whole list, collide itself. need add check in collision see if it's being compared itself. like

if (b == list.get(i)) {     continue; }