Requirements analysis:
We received an order from BMW and Mercedes-Benz. They are responsible for defining the parts and models of the products, and we are responsible for production. The simple description of the requirements is like this. We need to design a design pattern for this requirement to better adapt to their needs.
First we need a car model class to define all the required parts. This is called an abstract class. The reason for this is because we may receive orders from more companies, such as Rolls-Royce and Bentley. .
Then each car inherits this abstract class and implements the methods inside.
Next, you need a builder abstract class to define the methods needed to build your own car
Then each car builder inherits this abstract class.
We will think of a construction mode, yes, it is the builder mode. It's perfect to use. Take a look at the builder’s use case diagram
Please note: The method part of the example in this picture does not match my example.
Directly upload the code:
<span> 1</span> <?<span>php
</span><span> 2</span>
<span> 3</span> <span>abstract</span> <span>class</span><span> carModel{
</span><span> 4</span>
<span> 5</span> <span>//</span><span>这里存储所有组装车需要的零件</span>
<span> 6</span> <span>public</span> <span>$spareParts</span> = <span>array</span><span>();
</span><span> 7</span>
<span> 8</span> <span>//</span><span>车的名字</span>
<span> 9</span> <span>public</span> <span>$carName</span> = ""<span>;
</span><span> 10</span>
<span> 11</span> <span>//</span><span>增加轮子部件</span>
<span> 12</span> <span>public</span> <span>abstract</span> <span>function</span> addLunzi(<span>$xinghao</span><span>);
</span><span> 13</span>
<span> 14</span> <span>//</span><span>增加外壳部件</span>
<span> 15</span> <span>public</span> <span>abstract</span> <span>function</span> addWaike(<span>$xinghao</span><span>);
</span><span> 16</span>
<span> 17</span> <span>//</span><span>增加发动机部件</span>
<span> 18</span> <span>public</span> <span>abstract</span> <span>function</span> addFadongji(<span>$xinghao</span><span>);
</span><span> 19</span>
<span> 20</span> <span>//</span><span>获取车，并给车取名字</span>
<span> 21</span> <span>final</span> <span>public</span> <span>function</span> getCar(<span>$carName</span><span>){
</span><span> 22</span> <span>if</span>(<span>$this</span>-><span>spareParts){
</span><span> 23</span> <span>$this</span>->carName = <span>$carName</span><span>;
</span><span> 24</span> <span>//</span><span>$k 代表部件名字
</span><span> 25</span> <span> //$v 代表型号</span>
<span> 26</span> <span>foreach</span>(<span>$this</span>->spareParts <span>as</span> <span>$k</span>=><span>$v</span><span>){
</span><span> 27</span> <span>$actionName</span> = "add" . <span>$k</span><span>;
</span><span> 28</span> <span>$this</span>-><span>$actionName</span>(<span>$v</span><span>);
</span><span> 29</span> <span> }
</span><span> 30</span> }<span>else</span><span>{
</span><span> 31</span> <span>throw</span> <span>new</span> <span>Exception</span>("没有汽车部件"<span>);
</span><span> 32</span>
<span> 33</span> <span> }
</span><span> 34</span> <span> }
</span><span> 35</span> <span>}
</span><span> 36</span>
<span> 37</span>
<span> 38</span> <span>//</span><span>定义具体的产品</span>
<span> 39</span> <span>class</span> bmwCarModel <span>extends</span><span> carModel{
</span><span> 40</span>
<span> 41</span> <span>public</span> <span>$spareParts</span> = <span>array</span><span>();
</span><span> 42</span> <span>public</span> <span>$carName</span> = ""<span>;
</span><span> 43</span>
<span> 44</span> <span>public</span> <span>function</span> addLunzi(<span>$xinghao</span><span>){
</span><span> 45</span> <span>echo</span> "宝马".<span>$this</span>->carName."的轮子，型号是" . <span>$xinghao</span> . "\n"<span>;
</span><span> 46</span> <span> }
</span><span> 47</span>
<span> 48</span> <span>public</span> <span>function</span> addWaike(<span>$xinghao</span><span>){
</span><span> 49</span> <span>echo</span> "宝马".<span>$this</span>->carName."的外壳，型号是" . <span>$xinghao</span> . "\n"<span>;
</span><span> 50</span> <span> }
</span><span> 51</span>
<span> 52</span> <span>public</span> <span>function</span> addFadongji(<span>$xinghao</span><span>){
</span><span> 53</span> <span>echo</span> "宝马".<span>$this</span>->carName."的发动机,型号是 " . <span>$xinghao</span> . "\n"<span>;
</span><span> 54</span> <span> }
</span><span> 55</span> <span>}
</span><span> 56</span>
<span> 57</span>
<span> 58</span> <span>//</span><span>定义具体的产品</span>
<span> 59</span> <span>class</span> benziCarModel <span>extends</span><span> carModel{
</span><span> 60</span>
<span> 61</span> <span>public</span> <span>$spareParts</span> = <span>array</span><span>();
</span><span> 62</span> <span>public</span> <span>$carName</span> = ""<span>;
</span><span> 63</span>
<span> 64</span> <span>public</span> <span>function</span> addLunzi(<span>$xinghao</span><span>){
</span><span> 65</span> <span>echo</span> "奔驰".<span>$this</span>->carName."的轮子，型号是" . <span>$xinghao</span> . "\n"<span>;
</span><span> 66</span> <span> }
</span><span> 67</span>
<span> 68</span> <span>public</span> <span>function</span> addWaike(<span>$xinghao</span><span>){
</span><span> 69</span> <span>echo</span> "奔驰".<span>$this</span>->carName."的外壳，型号是" . <span>$xinghao</span> . "\n"<span>;
</span><span> 70</span> <span> }
</span><span> 71</span>
<span> 72</span> <span>public</span> <span>function</span> addFadongji(<span>$xinghao</span><span>){
</span><span> 73</span> <span>echo</span> "奔驰".<span>$this</span>->carName."的发动机,型号是 " . <span>$xinghao</span> . "\n"<span>;
</span><span> 74</span> <span> }
</span><span> 75</span> <span>}
</span><span> 76</span>
<span> 77</span>
<span> 78</span>
<span> 79</span> <span>//</span><span>定义建造者</span>
<span> 80</span> <span>abstract</span> <span>class</span><span> carBuilder{
</span><span> 81</span> <span>public</span> <span>abstract</span> <span>function</span> setSpareParts(<span>$partsName</span> , <span>$xinghao</span><span>);
</span><span> 82</span>
<span> 83</span> <span>public</span> <span>abstract</span> <span>function</span> getCarModel(<span>$name</span><span>);
</span><span> 84</span> <span>}
</span><span> 85</span>
<span> 86</span>
<span> 87</span> <span>class</span> bmwBuilder <span>extends</span><span> carBuilder{
</span><span> 88</span> <span>private</span> <span>$bmwModel</span><span>;
</span><span> 89</span>
<span> 90</span> <span>public</span> <span>function</span><span> __construct(){
</span><span> 91</span> <span>$this</span>->bmwModel = <span>new</span><span> bmwCarModel();
</span><span> 92</span> <span> }
</span><span> 93</span>
<span> 94</span> <span>public</span> <span>function</span> setSpareParts(<span>$partsName</span> , <span>$xinghao</span><span>){
</span><span> 95</span> <span>$this</span>->bmwModel->spareParts[<span>$partsName</span>] = <span>$xinghao</span><span>;
</span><span> 96</span> <span> }
</span><span> 97</span>
<span> 98</span> <span>public</span> <span>function</span> getCarModel(<span>$name</span><span>){
</span><span> 99</span> <span>$this</span>->bmwModel->getCar(<span>$name</span><span>);
</span><span>100</span> <span> }
</span><span>101</span> <span>}
</span><span>102</span>
<span>103</span>
<span>104</span> <span>class</span> benziBuilder <span>extends</span><span> carBuilder{
</span><span>105</span> <span>private</span> <span>$benziModel</span><span>;
</span><span>106</span>
<span>107</span> <span>public</span> <span>function</span><span> __construct(){
</span><span>108</span> <span>$this</span>->benziModel = <span>new</span><span> benziCarModel();
</span><span>109</span> <span> }
</span><span>110</span>
<span>111</span> <span>public</span> <span>function</span> setSpareParts(<span>$partsName</span> , <span>$xinghao</span><span>){
</span><span>112</span> <span>$this</span>->bmwModel->spareParts[<span>$partsName</span>] = <span>$xinghao</span><span>;
</span><span>113</span> <span> }
</span><span>114</span>
<span>115</span> <span>public</span> <span>function</span> getCarModel(<span>$name</span><span>){
</span><span>116</span> <span>$this</span>->bmwModel->getCar(<span>$name</span><span>);
</span><span>117</span> <span> }
</span><span>118</span> <span>}
</span><span>119</span>
<span>120</span>
<span>121</span>
<span>122</span> <span>//</span><span>模拟客户端调用
</span><span>123</span>
<span>124</span> <span>//创建一辆宝马车，取名字为宝马x1</span>
<span>125</span>
<span>126</span> <span>$bmwBuilder</span> = <span>new</span><span> bmwBuilder();
</span><span>127</span> <span>$bmwBuilder</span>->setSpareParts('Lunzi' , '牛逼轮子1号'<span>);
</span><span>128</span> <span>$bmwBuilder</span>->setSpareParts('Waike' , '牛逼外壳1号'<span>);
</span><span>129</span> <span>$bmwBuilder</span>->setSpareParts('Fadongji' , '牛逼发动机1号'<span>);
</span><span>130</span> <span>$bmwBuilder</span>->getCarModel("宝马x1"<span>);
</span><span>131</span> <span>$bmwBuilder</span>->getCarModel("宝马x1"); <span>//</span><span>连续创建两个宝马x1
</span><span>132</span>
<span>133</span> <span>//再创建一个宝马 没有外壳 取名为 宝马s5</span>
<span>134</span> <span>$bmwBuilder</span> = <span>new</span><span> bmwBuilder();
</span><span>135</span> <span>$bmwBuilder</span>->setSpareParts('Lunzi' , '牛逼轮子2号'<span>);
</span><span>136</span> <span>$bmwBuilder</span>->setSpareParts('Fadongji' , '牛逼发动机2号'<span>);
</span><span>137</span> <span>$bmwBuilder</span>->getCarModel("宝马s5"<span>);
</span><span>138</span> <span>$bmwBuilder</span>->getCarModel("宝马s5"); <span>//</span><span>连续创建两个宝马x1</span>The code can be run directly, and you can try to produce an awesome Mercedes-Benz car.
Builder Pattern is also called Generator Pattern, which is defined as follows:
Separate the construction of a complex object from its representation so that the same construction process can create different representations. Separate the construction of a complex object from its representation so that the same construction process can create different representations. representation.
The general class diagram of the builder pattern is shown in the figure.
In builder mode, there are four characters as follows:
Usually the template method pattern is implemented, that is, there are template methods and basic methods. Please refer to the template method pattern in the previous chapter. In the example, BenzModel and BMWModel belong to the product category.
The construction of standardized products is generally implemented by subclasses. In the example, CarBuilder is an abstract builder.
Implement all methods defined by the abstract class and return a component object. In the example, BenzBuilder and BMWBuilder are concrete builders.
Responsible for arranging the order of existing modules, and then telling the Builder to start building. In the above example, it is our boss. Niucha Company found the boss and said I want this, this, and that type of vehicle model, and then the boss will The order was passed to me, and my team and I started working hard to build, and a project was completed.
You don’t have to specifically look for ‘php design pattern’, you can look for ‘design pattern’ or ‘java design pattern’ which are easier to find. Because design patterns are not specific to a certain language but an idea, the design ideas you get are the same whether you look at 'php design pattern' or 'java design pattern' or 'design pattern'
If you use UserFactory, you don’t need to know the existence of the User class. The abstract class will help you hide it. If there are more classes in the future, this pattern will be more convenient to maintain. It is recommended that you learn about the abstract factory pattern, factory pattern, and factory. Method patterns, these are all means for reusable programming.
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