Java – 无法解决构造函数

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英文:

Java - Cannot resolve constructor

问题

我是Java编程新手。我有三个类,分别是 MainPointRectangle。我可以使用 Rectangle 类中的所有构造函数,除了这个:Rectangle(Point p, int w, int h)。Java编译器报错:“无法解析构造函数 'Rectangle(java.awt.Point, int, int)'”。谢谢。

以下是我的类:

Main.java

import java.awt.*;
import java.awt.Point;
import java.awt.Rectangle;

public class Main {

    public static void main(String[] args) {
        Point originOne = new Point(5,10);   
        Rectangle rectOne = new Rectangle(originOne, 100, 200);
    }

}

Point.java

public class Point {
    public int x = 0;
    public int y = 0;
    //构造函数
    public Point(int a, int b){
        x = a;
        y = b;
    }
}

Rectangle.java

public class Rectangle {
    public Point origin;
    public int width = 0;
    public int height = 0;

    //四个构造函数
    public Rectangle() {
        origin = new Point(0, 0);
    }
    public Rectangle(Point p){
        origin = p;
    }
    public Rectangle(int w, int h){
        origin = new Point(0,0);
        width = w;
        height = h;
    }
    public Rectangle(Point p, int w, int h) {
        origin = p;
        width = w;
        height = h;
    }

    // 移动矩形的方法
    public void move(int x, int y) {
        origin.x = x;
        origin.y = y;
    }

    // 计算矩形面积的方法
    public int getArea() {
        return width * height;
    }
}
英文:

I am new to Java programming. I have three classes which are Main, Point and Rectangle. I can use all constructors in Rectangle class except this one: Rectangle(Point p, int w, int h). Java compiler gives: "Cannot resolve constructor 'Rectangle(java.awt.Point, int, int)'" error. Thanks.

Here my classes:

Main.java

import java.awt.*;
import java.awt.Point;
import java.awt.Rectangle;

public class Main {

    public static void main(String[] args) {
        Point originOne = new Point(5,10);   
        Rectangle rectOne = new Rectangle(originOne, 100, 200);
    }

}

Point.java

public class Point {
    public int x = 0;
    public int y = 0;
    //contructor
    public Point(int a, int b){
        x = a;
        y = b;
    }
}

Rectangle.java

public class Rectangle {
    public Point origin;
    public int width = 0;
    public int height = 0;

    //four contructors
    public Rectangle() {
        origin = new Point(0, 0);
    }
    public Rectangle(Point p){
        origin = p;
    }
    public Rectangle(int w, int h){
        origin = new Point(0,0);
        width = w;
        height = h;
    }
    public Rectangle(Point p, int w, int h) {
        origin = p;
        width = w;
        height = h;
    }

    // a method for moving the rectangle
    public void move(int x, int y) {
        origin.x = x;
        origin.y = y;
    }

    //a method for computing the area of rectangle
    public int getArea() {
        return width * height;
    }
}

答案1

得分: 4

你的答案相对简单。你导入了错误的包,而不是导入java.awt.Rectangle,应该导入你自己的类。

通过这样做:

import <你的项目名称>.Rectangle;

如果我在Eclipse中有一个名为MyShapes的项目,其中包含相同的类,我会这样导入:

import MyShapes.Rectangle;

当然,这取决于你的文件结构是如何的,如果它在一个子文件夹(子包)中,我会这样做:

import MyShapes.ShapesClasses.Rectangle;

如果你计划使用自己的Point类而不是Java.awt的Point类,同样的规则也适用!

英文:

Your answer is fairly simple. You've imported the wrong import, rather than import java.awt.Rectangle, import your own class.

By doing:

import &lt;nameOfTheProject&gt;.Rectangle;

If I had a project in Eclipse called MyShapes and had the same classes. I would import it like:

import MyShapes.Rectangle;

Now this obviously depends on how your file structure is, but if it's inside a sub-folder (sub-package), I would do like:

import MyShapes.ShapesClasses.Rectangle;

This also applies to the Point class if you're planning on using your own Point class and not Java.awt's one!

huangapple
  • 本文由 发表于 2020年8月12日 17:16:34
  • 转载请务必保留本文链接:https://go.coder-hub.com/63373472.html
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