Google Guice嵌套辅助注入

Question

我有一个工厂是这样的：

public class Factory {

    public Client createClient(String url) {
        UrlBuilder urlBuilder = new UrlBuilder(url);

        DefaultHttpClient httpClient = new DefaultHttpClient();
        HttpProcessor processor = new CompressionHttpProcessor();
        httpClient.addRequestInterceptor(processor);
        httpClient.addResponseInterceptor(processor);

        return new Client(httpClient, urlBuilder);
    }
}

这样的类：

public class Facade {

    private Factory factory;
    private String url;

    public Facade(Factory factory) {
        this.factory = factory;
    }

    public void doStuff() {
        Client client = factory.createClient(url);
        // do stuff with client
    }

    public void setUrl(String url) {
        this.url = url;
    }
}

如何正确使用Google Guice来做同样的事情？我尝试了辅助注射，但我不确定如何创建“UrlBuilder”。谁能帮忙？

Answer 1

我创建了一个保存URL的Setting类，并执行了以下操作：

public MyModule extends AbstractModule {
    private final Settings settings;
    public MyModule(Settings settings) {
        this.settings = settings;
    }

    // configure

    @Provides
    private UrlBuilder createUrlBuilder(Settings settings) {
        return new UrlBuilder(settings.getUrl());
    }
}

它有点工作，但我不确定我喜欢它。

Answer 2

Guice减轻了对工厂和在Java代码中使用新代码的需求。

您的工厂代码似乎违反了这一原则。

您可能希望重新设计外观，以便它通过注入（使用 setClient）方法接收客户端对象。