Java Eclipse IDE 類型錯誤解決錯誤

Question

我從代碼的第一行得到一個錯誤，說 GeometricObject 無法解析為類型錯誤，我該如何修復它？ 問題是什么？

class Triangle extends GeometricObject implements Comparable<Triangle>
{
    private int a;
    private int b;
    private int c;
    private String color;
    private boolean isFilled;
    public Triangle(int a, int b, int c, String color, boolean filled){
          this.a = a;
          this.b = b;
          this.c = c;
          this.color = color;
          this.isFilled = filled;
    }
    public int getA(){return a;}
    public int getB(){return b;}
    public int getC(){return c;}
    public String getColor(){return color;}
    public boolean getIsFilled(){return isFilled;}
    public double getPerimeter(){
        return (a + b + c) ;
    }
    public double getArea(){
        double s = (a + b + c)/2;
        return Math.round(Math.sqrt(s*(s-a)*(s-b)*(s-c)));
    }
    public int compareTo(Triangle tri){  
       if(getArea()==tri.getArea())  
          return 0;  
       else if(getArea() > tri.getArea())  
          return 1;  
       else  
          return -1;  
    } 
    public boolean equals(Triangle tri){
        if(a==tri.getA() && b == tri.getB() && c== tri.getC() && color.equals(tri.getColor()) && isFilled == tri.getIsFilled())
            return true;
        return false;      
    }
    public String toString(){
        return "Triangle Color: "+color+"\tisFilled: "+isFilled+"\t Side A: "+a+"\tSide B: "+b+"\tSide C: "+c+"\tPerimeter: "+getPerimeter()
               +"\tArea: "+getArea()+"\n";
    }
}
public class TriangleTest
{
    public static void main(String[] args) 
    {
        java.util.ArrayList<Triangle> list = new java.util.ArrayList<Triangle>(); 
        Triangle t1 = new Triangle(10, 10, 10, "Black", false);
        Triangle t2 = new Triangle(12, 12, 12, "Green", true);
        Triangle t3 = new Triangle(12, 12, 12, "Green", true);
        Triangle t4 = new Triangle(20, 20, 20, "Blue", false);
        Triangle t5 = new Triangle(8, 8, 8, "Yellow", true);
        list.add(t1);
        list.add(t2);
        list.add(t3);
        list.add(t4);
        list.add(t5);
        System.out.println("\t\t\t\t############# Displaying Triangle Details ################\n");
        list.forEach(tri -> System.out.println(tri));
        System.out.println("\t\t\t############# Displaying Triangle Details after sorting ################\n");      
        java.util.Collections.sort(list);
        list.forEach(tri -> System.out.println(tri));
    }
}

Answer 1

這意味着您尚未導入任何“GeometricObject”class。

如果您使用外部庫，請檢查它是否已正確導入。 如果您使用的是您制作的抽象 class，那么只需導入它。

PS：請嘗試寫更清晰的問題描述，不需要垃圾郵件:)