Java贪吃蛇原地回头

Java贪吃蛇如何解决按的太快蛇原地回头的问题

if (isStart&&!isOver){
//蛇移动的方法
if(dir.equals("R")){
this.follow();//这个是蛇身体往头的方向移动一格的方法
snakeX[0] = snakeX[0] + 25;
}
if(dir.equals("L")){
this.follow();
snakeX[0] = snakeX[0] - 25;
}
if(dir.equals("U")){
this.follow();
snakeY[0] = snakeY[0] - 25;
}
if(dir.equals("D")){
this.follow();
snakeY[0] = snakeY[0] + 25;
}
//边界判断
if (snakeX[0]<0||snakeX[0]>775){
isOver = true;
}
if (snakeY[0]<50||snakeY[0]>575){
isOver = true;
}
//撞到自己判断
for (int i = 1; i < length; i++) {
if (snakeX[0] == snakeX[i] && snakeY[0] == snakeY[i]) {
isOver = true;
break;
}
}
//吃到食物(蛇头碰到食物)长度加1，刷新食物位置
if(snakeX[0]==foodX&&snakeY[0]==foodY){
length++;
food();
}
repaint();
}

......好了xdm，解决了