public void move(){
		if( this.direction == Bullet.direction_up){
			this.location_y -= this.speed ;
		}else if(this.direction == Bullet.direction_down){
			this.location_y += this.speed ;
		}else if(this.direction == Bullet.direction_left){
			this.location_x -= this.speed ;
		}else if(this.direction == Bullet.direction_right){
			this.location_x += this.speed ;
		}
		
		if( this.location_x <= 0 || this.location_x >= this.active_area_x || this.location_y <= 0 || this.location_y >= this.active_area_y)
			this.setStatus(DEAD);
	}