求教小疑点（boolean赋值有关问题）

求教小问题（boolean赋值问题）
前面是Car类和CarStatus类，后面是测试类TestCar，问题：最后面ff的两次赋值，只能赋一次，第二次编译时就会出现错误： 无法访问的语句 ff = trafficAdmin.isLegalSpeed(trafficAdmin.getCarStatus(normalCar)); 不知为什么？大神帮帮忙！！！

public class Car {
String name = "haha";
String color;
String direction;
int speed;
boolean isTrafficAdmin;

public Car() {
this(50,"beijing");
}

public Car(int p_speed,String p_direction) {
this(p_speed,p_direction,false);
}

public Car(int p_speed,String p_direction,boolean isTrafficAdmin) {
this.speed = p_speed;
this.direction = p_direction;
this.isTrafficAdmin = isTrafficAdmin;
}

public void dirveCar() {
speed = 50;
direction = "beijing";
}

public void raiseSpeed (int p_speed) {
if(p_speed < 0) {
System.out.println("加速度不能为负数");
return;
}else {
int currentspeed = speed + p_speed;
speed = currentspeed;
}
}

public void raiseSpeed (byte p_speed) {
if(p_speed < 0) {
System.out.println("加速度不能为负数");
return;
}else {
int currentspeed = speed + p_speed;
speed = currentspeed;
}
}

public void overTakeCar( Car another) {
speed = another.speed + 5;
direction = another.direction;
}

public void setSpeedAndDirection(int p_speed,String direction) {
speed = p_speed;
this.direction = direction;
}

public boolean isOverSpeed() {
if (speed > 60) {
return true;
}else
return false;
}

public void setAnotherCarName(Car another,String newName) {
if(!isTrafficAdmin) {
System.out.println("你没有权限");
return;
}else {
another.name = newName;
}
}

public void setSpeed(Car another) {
if(!isTrafficAdmin) {
System.out.println("你没有权限");
return;
}else {
another.speed = 0;
}
}

public CarStatus getCarStatus(Car another) {
CarStatus status = new CarStatus(another.speed,another.direction);
return status;
}

public boolean isLegalSpeed(CarStatus status) {
if(status.speed<=60) {
return true;
}else {
return false;
}
}

public void printCar() {
System.out.println(speed);
System.out.println(direction);
}
}


 public class CarStatus {
int speed;
String direction;

  public CarStatus() {
  }
   
  public CarStatus(int p_speed,String direction) {
  this.speed = p_speed;
  this.direction = direction;
  }
  }


public class TestCar {
public static void main(String[] args) {
Car normalCar = new Car();
normalCar.printCar();
Car crazyCar = new Car();
crazyCar.printCar();
Car trafficAdmin = new Car(40,"beijing",true);
trafficAdmin.printCar();
crazyCar.raiseSpeed(10);
crazyCar.printCar();
crazyCar.raiseSpeed((byte)10);
crazyCar.printCar();
normalCar.overTakeCar(crazyCar);
normalCar.printCar();
normalCar.setSpeedAndDirection(50,"beijing");
normalCar.printCar();
/*boolean ff = trafficAdmin.isLegalSpeed(trafficAdmin.getCarStatus(normalCar));
if(ff) {
trafficAdmin.setAnotherCarName(normalCar,"good");
System.out.println(normalCar.name);
return;  
}else {
return;
}*/
//normalCar.printCar(); 这句怎么无法访问呢？
 
boolean ff = trafficAdmin.isLegalSpeed(trafficAdmin.getCarStatus(crazyCar));
if(ff) {
trafficAdmin.setAnotherCarName(normalCar,"good");