Question

我有两个列表，具有完全相同的值，但是当我使用equal（）方法时，它返回false ...有人可以帮助我......这是我的代码。

@Test
public void testPolygonConstructor(){
    try {
        Triangle t = new Triangle("Triangle 3 4 9 4 3 8");
        Point a1 = new Point(3,4);
        Point a2 = new Point(9,4);
        Point a3 = new Point(3,8);
        List<Object> list = new ArrayList<Object>(Arrays.asList(a1,a2,a3));
        System.out.println(t.coordenadas);
        System.out.println(list);
        System.out.println(t.coordenadas.equals(list));

    } catch (Exception e) {

    }
}

我的输出是：

[3 4,9 4,3 8]
  [3 4,9 4,3 8]
  假

编辑：三角级

public class Triangle extends Polygon {
    public Triangle(String s) throws Exception {
        super(s);
        if (!isValid()) {
            throw new Exception();
        }
    }

    public boolean isValid() {
        if (isAllEqual() || coordenadas.size() != 3) {
            return false;
        }
        double lado1 = coordenadas.get(0).dist(coordenadas.get(1));
        double lado2 = coordenadas.get(0).dist(coordenadas.get(2));
        double lado3 = coordenadas.get(1).dist(coordenadas.get(2));
        if (lado1 + lado2 > lado3 && lado1 + lado3 > lado2 && lado2 + lado3 > lado1) {
            return true;
        }

        return false;
    }

}

我的多边形类（三角形的超类是=）

import java.util.List;
import java.util.Scanner;
import java.util.ArrayList;

public abstract class Polygon {
    protected List<Point> coordenadas = new ArrayList<Point>();

    public Polygon(String s) throws Exception {
        coordenadas = readPoints(s);
        if (coordenadas.isEmpty()) {
            throw new Exception();
        }
    }

    private List<Point> readPoints(String s) {

        s = s.replaceAll("[^0-9]+", " ");
        s.trim().split(" ");
        Scanner scanner = new Scanner(s);
        List<Integer> list = new ArrayList<Integer>();
        while (scanner.hasNextInt()) {
            list.add(scanner.nextInt());
        }
        scanner.close();
        int j = 0;
        for (int i = 0; i < list.size() - 1; i += 2) {
            Point k = new Point(list.get(i), list.get(i + 1));
            coordenadas.add(j, k);
            j++;
        }
        return coordenadas;

    }

    public Point centroid() {
        double x = 0;
        double y = 0;
        for (int i = 0; i < coordenadas.size(); i++) {
            x += coordenadas.get(i).getX();
            y += coordenadas.get(i).getY();
        }

        x = x / coordenadas.size();
        y = y / coordenadas.size();
        return new Point((int) x, (int) y);

    }

    public double perimeter() {
        double distance = 0;
        int len = coordenadas.size();
        for (int i = 0; i < len; i++) {
            distance += coordenadas.get(i).dist(coordenadas.get((i + 1) % len));
        }
        return distance;
    }

    public boolean isAllEqual() {
        Point first = coordenadas.get(0);
        for (int i = 1; i < coordenadas.size(); i++) {
            if (!coordenadas.get(i).Equals(first))
                return false;
        }
        return true;
    }

    public abstract boolean isValid();                          

}

我猜问题可能是“coordenadas”受到保护???

EDIT2：这里是点类抱歉的人!!

public class Point {

    private double x = 0, y = 0;

    public Point(double x, double y) {
        this.x = x;
        this.y = y;
    }

    public double getX() {
        return this.x;
    }

    public double getY() {
        return this.y;
    }

    public boolean Equals(Point p) {
        return this.x == p.getX() && this.y == p.getY();
    }

    public double dist(Point p) {
        double dx = getX() - p.getX();
        double dy = getY() - p.getY();
        return Math.sqrt(dx * dx + dy * dy);
    }

    public String toString() {
        return ((int) getX() + " " + (int) getY());
    }
}

Answer 1

您的Point课程未覆盖equals的{{1}}方法。

您可以将方法Object更改为Equals

或将此方法添加到equals类：

Point

Answer 2

Triangle课程是你创造的吗？您需要使用自己的实现重载equals（Object o）方法。否则，将使用默认的equals方法。由于这些是两个不同的对象，结果将是错误的。

这只是一个开始

if($this->upload->do_upload('menu_image')){

    $uploaded_data = $this->upload->data(); //get the uploaded image information

    $this->resize_uploaded_image($uploaded_data); //send for resizing

    //example of saving IMAGE FILENAME TO DB, YOU CAN OPT TO SAVE FULLPATH
    $this->model->save_image_filename($uplodated_data['filename']);
   }else{
    ...
   }


//resizer
public function resize_uploaded_image($image_data)
{
   $config = array(
        'image_library'     => 'gd2',
        'source_image'      => $image_data['full_path'], //uploaded imagepath
        'create_thumb'      => 'true',
        'width'             =>  575,
        'height'            =>  550,
    );

   $this->load->library('image_lib', $config);  
   $this->image_lib->resize(); 
}

返回false的等号列表 - Java

2 个答案: