1.1. 抽象工厂

1.1.1. 目的

创建一系列互相关联或依赖的对象时，不指定他们具体的类。因为这些创建的类通常都实现了同一个接口。抽象工厂的客户端并不关心对象是如何创建的，而只知道它们是怎样组合的。

1.1.2. UML 图

Alt AbstractFactory UML Diagram

1.1.3. 代码

在 GitHub 上查看代码

WriterFactory.php

1<?php
2
3namespace DesignPatterns\Creational\AbstractFactory;
4
5interface WriterFactory
6{
7    public function createCsvWriter(): CsvWriter;
8    public function createJsonWriter(): JsonWriter;
9}

CsvWriter.php

1<?php
2
3namespace DesignPatterns\Creational\AbstractFactory;
4
5interface CsvWriter
6{
7    public function write(array $line): string;
8}

JsonWriter.php

1<?php
2
3namespace DesignPatterns\Creational\AbstractFactory;
4
5interface JsonWriter
6{
7    public function write(array $data, bool $formatted): string;
8}

UnixCsvWriter.php

 1<?php
 2
 3namespace DesignPatterns\Creational\AbstractFactory;
 4
 5class UnixCsvWriter implements CsvWriter
 6{
 7    public function write(array $line): string
 8    {
 9        return join(',', $line) . "\n";
10    }
11}

UnixJsonWriter.php

 1<?php
 2
 3namespace DesignPatterns\Creational\AbstractFactory;
 4
 5class UnixJsonWriter implements JsonWriter
 6{
 7    public function write(array $data, bool $formatted): string
 8    {
 9        $options = 0;
10
11        if ($formatted) {
12            $options = JSON_PRETTY_PRINT;
13        }
14
15        return json_encode($data, $options);
16    }
17}

UnixWriterFactory.php

 1<?php
 2
 3namespace DesignPatterns\Creational\AbstractFactory;
 4
 5class UnixWriterFactory implements WriterFactory
 6{
 7    public function createCsvWriter(): CsvWriter
 8    {
 9        return new UnixCsvWriter();
10    }
11
12    public function createJsonWriter(): JsonWriter
13    {
14        return new UnixJsonWriter();
15    }
16}

WinCsvWriter.php

 1<?php
 2
 3namespace DesignPatterns\Creational\AbstractFactory;
 4
 5class WinCsvWriter implements CsvWriter
 6{
 7    public function write(array $line): string
 8    {
 9        return join(',', $line) . "\r\n";
10    }
11}

WinJsonWriter.php

 1<?php
 2
 3namespace DesignPatterns\Creational\AbstractFactory;
 4
 5class WinJsonWriter implements JsonWriter
 6{
 7    public function write(array $data, bool $formatted): string
 8    {
 9        $options = 0;
10
11        if ($formatted) {
12            $options = JSON_PRETTY_PRINT;
13        }
14
15        return json_encode($data, $options);
16    }
17}

WinWriterFactory.php

 1<?php
 2
 3namespace DesignPatterns\Creational\AbstractFactory;
 4
 5class WinWriterFactory implements WriterFactory
 6{
 7    public function createCsvWriter(): CsvWriter
 8    {
 9        return new WinCsvWriter();
10    }
11
12    public function createJsonWriter(): JsonWriter
13    {
14        return new WinJsonWriter();
15    }
16}

1.1.4. 测试

Tests/AbstractFactoryTest.php

 1<?php
 2
 3declare(strict_types=1);
 4
 5namespace DesignPatterns\Creational\AbstractFactory\Tests;
 6
 7use DesignPatterns\Creational\AbstractFactory\CsvWriter;
 8use DesignPatterns\Creational\AbstractFactory\JsonWriter;
 9use DesignPatterns\Creational\AbstractFactory\UnixWriterFactory;
10use DesignPatterns\Creational\AbstractFactory\WinWriterFactory;
11use DesignPatterns\Creational\AbstractFactory\WriterFactory;
12use PHPUnit\Framework\TestCase;
13
14class AbstractFactoryTest extends TestCase
15{
16    public function provideFactory()
17    {
18        return [
19            [new UnixWriterFactory()],
20            [new WinWriterFactory()]
21        ];
22    }
23
24    /**
25     * @dataProvider provideFactory
26     */
27    public function testCanCreateCsvWriterOnUnix(WriterFactory $writerFactory)
28    {
29        $this->assertInstanceOf(JsonWriter::class, $writerFactory->createJsonWriter());
30        $this->assertInstanceOf(CsvWriter::class, $writerFactory->createCsvWriter());
31    }
32}