小白求解答 java，为啥会出现这个问题

Question

class Rectangle {
private int width;
private int high;
public Rectangle(){}
public Rectangle(int width,int high){
this.width = width;
this.high = high;
}
public void setWidth(){
this.width = width;
}

public int getWidth(int width){
    return width;
}

public void setHigh(){
    this.high = high;
}

public int getHigh(int high){
    return high;
}

public int getLength(){
    return 2*(width+high);
}

public int getArea(){
    return width*high;
}

}

class Test3_Rectangle {
public static void main(String[] args) {
Rectangle re = new Rectangle();
re.setWidth(30);

re.setHigh(40);
System.out.println("周长为"+re.getLength()+" "+"面积为"+re.getArea());
}
}

Answer 1

实体类的get set方法错误， get方法一般不带参只有set方法带参