swing - at java.awt.AWTEventMulticaster.mouseExited(Unknown Source) occur after using the GUI for several times -

good morning, i'm implementing gui game , when play game sometime endless number of exception game freezes, on problem or how fix appreciated

here code:

public class boardframe extends jframe implements mouselistener {       private void boardwithoutcheckers() {           for(int i=0; i<8; i++) {             for(int j=0; j< 8; j++) {                 if(((i + j) % 2) == 0){                     boardframe[i][j] = new lightgraybutton();                      }                     else {                         boardframe[i][j] = new darkgraybutton();                     }                 boardframe[i][j].addmouselistener(this);                  this.getcontentpane().add(boardframe[i][j]);             }          }         this.setvisible(true);     }    @override public void mouseclicked(mouseevent e) {        count++;     if(count == 1){     (int = 0; < 8; i++) {         (int j = 0; j < 8; j++) {             if(e.getsource().equals(boardframe[i][j])){                 possiblemoves = board.getpossiblemoves(new point(j,i));             (int k = 0; k < possiblemoves.size(); k++) {                  point temp = new point(possiblemoves.get(k).getx(),possiblemoves.get(k).gety());                 boardframe[temp.gety()][temp.getx()].setbackground(new color(99,204,94,50));             }             firstclick = new point(j, i);             break;             }             }         }      }     if(count == 2){          (int = 0; < 8; i++) {             (int j = 0; j < 8; j++) {                 if(e.getsource().equals(boardframe[i][j])){                   (int k = 0; k < possiblemoves.size(); k++) {                     if(possiblemoves.get(k).getx() == j && possiblemoves.get(k).gety() == i){                         if(board.getturn() == 1){                         boardframe[i][j].seticon(null);                         boardframe[i][j].seticon(new imageicon(earth));                         boardframe[firstclick.gety()][firstclick.getx()].seticon(null);                         board.move(firstclick, new point(j,i));                            }                         else if(board.getturn() == 2){                             boardframe[i][j].seticon(null);                             boardframe[i][j].seticon(new imageicon(mars));                             boardframe[firstclick.gety()][firstclick.getx()].seticon(null);                             board.move(firstclick, new point(j,i));                              break;                         }                   }                  }                 }                 }      }          count=0;         possiblemoves = new arraylist<point>();         for(int i=0; i<8; i++) {             for(int j=0; j< 8; j++) {                 if(((i + j) % 2) == 0){                     boardframe[i][j].setbackground(new color(15, 81, 162));                      }                     else {                         boardframe[i][j].setbackground(new color(77, 77, 77));                     }                 boardframe[i][j].addmouselistener(this);             }      }     }      if(board.isgameover()){         jlabel winner = new jlabel("we have winner");         this.getcontentpane().add(winner);     }     } 

the exception massage endless number of @ java.awt.awteventmulticaster.mouseexited(unknown source)

im pretty sure board class 100% made teacher assistants in our university , passed test

thanks in advance

i see potential source of problems:

     (int = 0; < 8; i++) {         (int j = 0; j < 8; j++) {            if (((i + j) % 2) == 0) {               boardframe[i][j].setbackground(new color(15, 81, 162));             } else {               boardframe[i][j].setbackground(new color(77, 77, 77));            }            boardframe[i][j].addmouselistener(this); // !! here !!         }       } 

i keyed in error involved swing mouse handling. appear adding mouselistener multiple times components. picture this, when mouselistener called, adds mouselistener same component. next mousepress, mouselistener called twice , two mouselisteners added, 4, 8, 16, ... lead geometric increase in number of mouselisteners added whenever 1 called, , overwhelm system.

solution:

1. don't this. don't add same listener component inside of listener code.
2. again, don't use mouselisteners @ jbuttons. use actionlisteners.