C++对象模型深度解析:面向对象编程的秘密机制

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《深入C++对象模型》是一本经典的计算机科学著作,专注于剖析C++语言中支持面向对象编程的核心机制。该书的核心内容围绕以下几个关键主题展开: 1. 构造函数语义:作者详细解释了构造函数在创建和初始化对象时的作用,包括它们的执行顺序、参数传递以及与析构函数(destructor)的配合。理解这些概念有助于开发者编写更加高效和可靠的代码。 2. 暂时对象生成:书中讨论了在C++中的临时对象是如何产生的,这对于函数调用和对象生命周期管理至关重要,尤其是在高并发和性能优化的场景下。 3. 封装与隐藏实现:C++的对象模型强调封装,即通过访问控制符(如public、private、protected)来隐藏类的内部细节,提高代码的安全性和可维护性。作者揭示了关于封装的一些常见误解,同时指出其背后的真实成本和复杂性。 4. 继承与虚函数(Virtual Functions):书中深入探讨了继承机制,包括公有继承、私有继承和虚继承的区别,以及虚函数如何实现动态多态性。作者澄清了关于虚函数性能的普遍误区,并揭示了不同继承方式的选择和潜在的影响。 5. 性能分析与程序转换:书中分析了面向对象特性的实施对程序性能的影响,通过程序优化技术,讨论了如何在保持功能的同时最小化开销。作者揭示了那些可能被忽视的成本和折衷之处。 6. 实现模型的历史与演变:作者追溯了C++对象模型的发展历程,解释了各种设计决策的原因,并预测了未来可能的演进方向,帮助读者理解模型背后的逻辑。 7. 语义影响与编程实践:最后,作者讨论了C++对象模型对程序员编程习惯的具体影响,以及如何根据模型特性调整设计策略,以充分利用C++的优势。 《深入C++对象模型》是一本实用的指南,它不仅提供了理论深度,还为实际项目中的C++开发者提供了宝贵的洞见和策略,帮助他们更好地理解和利用C++的面向对象特性,提升代码质量和性能。

Write a Model class with the following UML specification: +----------------------------------------------+ | Model | +----------------------------------------------+ | - score: int | | - bubbles: ArrayList<IShape> | +----------------------------------------------+ | + Model() | | + getScore(): int | | + addBubble(int w, int h): void | | + moveAll(int dx, int dy): void | | + clearInvisibles(int w, int h): void | | + deleteBubblesAtPoint(int x, int y): void | | + drawAll(Graphics g): void | | + testModel(): void | +----------------------------------------------+ When a new model object is created, the score must be zero and the arraylist must be empty. The getScore method returns as result the current score for the game. The addBubble method adds a new bubble to the arraylist of bubbles. The position of the center of the new bubble is random but must be inside a window of width w and height h (the arguments of the addBubble method), like this: new Bubble((int)(w * Math.random()), (int)(h * Math.random())) The moveAll method moves the positions of all the bubbles in the arraylist of bubbles by the amount dx in the x direction and by the amount dy in the y direction. The clearInvisibles method takes as argument the width w and the height h of the window, and deletes from the arraylist of bubbles any bubble which is not visible in the window anymore. For each bubble which is deleted, the score decreases by 1.The deleteBubblesAtPoint method takes as argument the coordinates (x, y) of a point, and deletes from the arraylist of bubbles any bubble which contains this point (multiple bubbles might contain the point, because bubbles can overlap in the window). For each bubble which is deleted, the score increases by 1. The drawAll method draws all the bubbles in the arraylist of bub

2023-05-11 上传

帮我写出以下java代码:Add a class Bubble that extends Shape. The Bubble class has an instance variable called radius of type double that represents the radius of the bubble. The constructor of the Bubble class takes an x and a y as arguments, which represent the position of the new bubble. The radius of a new bubble is always 10 and never changes after that. The isVisible method indicates whether the bubble is currently visible inside a window of width w and height h (position (0, 0) is in the upper-left corner of the window). The bubble is considered visible if at least one pixel of the bubble is visible. Therefore a bubble might be visible even when its center is outside the window, as long as the edge of the bubble is still visible inside the window. The code of the isVisible method is a little bit complex, mostly because of the case where the center of the circle is just outside one of the corners of the window. So here is the code of the isVisible method, which you can directly copy-paste into your assignment: // Find the point (wx, wy) inside the window which is closest to the // center (x, y) of the circle. In other words, find the wx in the // interval [0, w - 1] which is closest to x, and find the wy in the // interval [0, h - 1] which is closest to y. // If the distance between (wx, wy) and (x, y) is less than the radius // of the circle (using Pythagoras's theorem) then at least part of // the circle is visible in the window. // Note: if the center of the circle is inside the window, then (wx, wy) // is the same as (x, y), and the distance is 0. public boolean isVisible(int w, int h) { double x = getX(); double y = getY(); double wx = (x < 0 ? 0 : (x > w - 1 ? w - 1 : x)); double wy = (y < 0 ? 0 : (y > h - 1 ? h - 1 : y)); double dx = wx - x; double dy = wy - y; return dx * dx + dy * dy <= radius * radius; } The isIn method indicates whether the point at coordinates (x, y) (which are the arguments of the method) is currently inside the bubble or not. The edge of the bubble counts as being inside of the bubble. HINT: use Pythagoras's theorem to compute the distance from the center of the bubble to the point (x, y). The draw method uses the graphics object g to draw the bubble. HINT: remember that the color of the graphics object g is changed in the draw method of the superclass of Bubble. Also add a testBubble method to test all your methods (including inherited methods, but excluding the isVisible method, which I provide, and excluding the draw method since it requires as argument a graphics object g that you

2023-05-22 上传