java - 这不是工厂模式吗？

Question

我正在和老师争论这是否是工厂模式。我可以得到你们的一些意见吗？

public class UrlFactory {
    private static boolean testMode;
    private static long testDate;

    public static URLConnection fetchConnection(String url) 
                                              throws IOException
    {
        URL address = new URL(url);

        if(testMode)
            return new MockURLConnection(address, testDate);
        return address.openConnection();
    }

    public static void SetTestMode(long testDate)
    {
        UrlFactory.testMode = true;
        UrlFactory.testDate = testDate;
    }

    public static void UnSetTestMode()
    {
        UrlFactory.testMode = false;
    }
}

Answer 1

它在结构上看起来与工厂类似，但我想说它忽略了工厂模式的要点。理想情况下，工厂是可实例化和可重写的(例如具有用于创建的虚拟方法)。我建议采用一种设计，其中 UrlFactory 是一个带有虚拟 fetchConnection 方法的非静态类。然后，您可以拥有一个派生类 MockUrlFactory，它重写 fetchConnection 以返回 MockURLConnection。

示例:

public class UrlFactory {
    public URLConnection fetchConnection(String url)
        throws IOException {
        URL address = new URL(url);
        return address.openConnection();
    }
}

public class MockUrlFactory extends UrlFactory {
    private long testDate;

    public MockUrlFactory(long testDate) {
        this.testDate = testDate;
    }

    public URLConnection fetchConnection(String url)
        throws IOException {
        URL address = new URL(url);
        return new MockURLConnection(address, testDate);
    }
}