Aways the same thread gets CPU time

Aways the same thread gets CPU time

Code is too large, so I'll just copy the part that is problematic.
This is run() method in one class:
public void run(){
try{
sleep(1000);
while(true){
synchronized(space){
if(end)
return;
if(space[X][Y] == null)
break;
if(((Ship)space[X][Y]).isDestroyed){
destroy();
break;
}
if(isThereAnyShipsInTheArea() != 0){
if(team != ((Ship)space[X][Y + isThereAnyShipsInTheArea()]).team){
fight(isThereAnyShipsInTheArea());
}
}
else
move();
if(isDestroyed){
destroy();
break;
}
}
}
}
catch(InterruptedException ie){
System.out.println("Interrupted exception!");
}
}
This is simulation of Star Trek. Variable team represends to which team
the ship belongs. Varable isDestroyed is true if the ship is destroyed in
battle or crash when moving. isThereAnyShipsInTheArea() - ship is within
range if the distance one or two. space is matrix whit dimensions
[90]x[90].
I think problem is in run method, but I'll give you some other methods.
private int isThereAnyShipsInTheArea(){
if(space[X][Y - 2] instanceof Ship && ((Ship)space[X][Y -
2]).isDestroyed == false)
return -2;
if(space[X][Y - 1] instanceof Ship && ((Ship)space[X][Y -
1]).isDestroyed == false)
return -1;
if(space[X][Y + 1] instanceof Ship && ((Ship)space[X][Y +
1]).isDestroyed == false)
return 1;
if(space[X][Y + 2] instanceof Ship && ((Ship)space[X][Y +
2]).isDestroyed == false)
return 2;
return 0;
}
private synchronized void fight(int meet){
while(((Ship)svemir[X][Y]).isDestroyed == false && ((Ship)space[X][Y +
meet]).isDestroyed == false){
if(((Ship)space[X][Y]).getProjectile() != 0){
((Ship)space[X][Y + meet]).setShield(((Ship)space[X][Y +
meet]).getShield() - 1);
((Ship)space[X][Y + meet]).setWarp(((Ship)space[X][Y +
meet]).getWarp() - 1);
((Ship)space[X][Y]).setProjectile(((Ship)space[X][Y]).getProjectile()
- 1);
if(((Ship)space[X][Y + meet]).getShield() == 0 || ((Ship)space[X][Y
+ meet]).getWarp() == 0){
((Ship)space[X][Y + meet]).isDestroyed = true;
return;
}
}
if(((Ship)space[X][Y + meet]).getProjectile() != 0){
((Ship)space[X][Y]).setShield(((Ship)space[X][Y]).getShield() - 1);
((Ship)space[X][Y]).setWarp(((Ship)space[X][Y]).getWarp() - 1);
((Ship)space[X][Y + meet]).setProjectile(((Ship)space[X][Y +
meet]).getProjectile() - 1);
if(((Ship)space[X][Y]).getShield() == 0 ||
((Ship)space[X][Y]).getWarp() == 0){
this.isDestroyed = true;
return;
}
}
if(((Ship)space[X][Y]).getProjectile() == 0 && ((Ship)space[X][Y +
meet]).getProjectile() == 0)
return;
}
}