OSGI DS @Reference

Question

我正在编写一个OSGI应用程序，其中包括动态＆amp;静态引用。每项服务都放在不同的包中。

@Reference (bind = "bindMethod", unbind = "unbindMethod", cardinality = ReferenceCardinality.MANDATORY_UNARY, policy = ReferencePolicy.DYNAMIC)
    private final AtomicReference<TestService> testService = new AtomicReference<TestService>();

@Reference (bind = "bindMethod", unbind = "unbindMethod", cardinality = ReferenceCardinality.MANDATORY_UNARY, policy = ReferencePolicy.DYNAMIC)
    private AtomicReference<TestService> testService = new AtomicReference<TestService>(); //final is ommitted

 protected void bindMethod(TestService atestService)
    {
        if (TestService.get() == null)
        {
            testService.set(atestService);
        }
    }

    protected void unbindMethod(TestService atestService)
    {
        myServices.compareAndSet(testService, null);
    }

没有AtomicReference

@Reference (bind = "bindMethod", unbind = "unbindMethod", cardinality = ReferenceCardinality.MANDATORY_UNARY, policy = ReferencePolicy.DYNAMIC)
    private TestService testService;

protected void bindMethod(TestService atestService)
    {
        testService = atestService;
    }

    protected void unbindMethod(TestService atestService)
    {
        testService = null;
    }

推荐哪一个以及每个产品对性能的影响是什么？

Answer 1

您将@Reference放在字段上意味着您正在使用DS 1.3及其新的字段注入支持。

在这种情况下，您不需要bind / unbind方法也不需要AtomicReference。只是：

@Reference private volatile TestService testService;

volatile意味着它是一个动态引用，并提供适当的并发访问。