The first thing which we’ve done in every example so far is configure a simple file poller on the file system.

到目前为止，我们在每个示例中所做的第一件事就是配置一个轮询文件系统的简单文件轮询器。

In the file poller implementation we just read a file from the file system and send the received file to the Mail service endpoint.

在这个文件轮询器配置中，我们仅仅从文件系统读取文件，然后把收到的文件发送给邮件服务端点。

It removes all the complexity of writing your own file system poller and, where possible, is based upon existing native system APIs for better performance.

这就免除了自己编写文件系统轮询程序的所有麻烦，并且，如果可能的话，它可基于本地系统 API 来获取更优的性能。

Listing 6.3 File poller configuration which sends the message to the mail service.

清单6.3 文件轮询器配置：向邮件服务发送消息

A poller is exactly what it sounds like: it's the mechanism that polls different endpoints for changes and, if some thing's perceived to have changed, let's the adapter react to it as an event.

确切来说，轮询器是一种机制，在有变化时轮询不同端点，并在感知到某些内容发生变化后让适配器对其做出响应，就像一个事件。

Create a service definition and a monitor definition in the /etc/poller-configuration.xml file.

在 /etc/poller-configuration.xml文件中创建服务定义和监控程序定义。

We should also insert a monitor definition in the same poller-configuration.xml file, as shown in Listing 10

在同一个poller-configuration.xml文件中，我们还应该插入monitor定义，如清单10 所示

This class must implement the org.opennms.netmgt.poller.ServiceMonitor interface.

该类必须实现org.opennms.netmgt.poller.ServiceMonitor接口。

To do this, we will create a plugin for the capability daemon (capsd) and a monitor for the poller daemon (pollerd).

要做到这一点，将创建用于功能守护程序（capsd）的插件和用于轮询器守护程序（pollerd）的监控程序。

The first stanza of actual configuration is the poller element, which is the default poller for the document.

实质配置的第一段是poller元素，它是文档的默认轮询器。

Create a class that implements the org.opennms.netmgt.poller.ServiceMonitor interface. Specifically, this interface has five methods that the monitor must implement, as listed in Table 3

创建实现org.opennms.netmgt.poller.ServiceMonitor接口的类。

The poller daemon, pollerd, will regularly poll detected services to ensure they are operational.

轮询器守护程序pollerd将定期轮询已检测到的服务以确保它们是可操作的。

After OpenNMS has determined the services on a managed node, it will use the poller daemon (pollerd) to regularly poll the managed devices/services to ensure that they are operational.

在OpenNMS确定了受管节点上的服务之后，它将使用轮询器守护程序（pollerd）来定期轮询受管设备／服务，以确保它们是可操作的。

The poller element is defined just once so that everything that needs a poller in the context can make use of a default one.

poller元素只定义了一次，这样，上下文中需要轮询器的所有内容都可以利用这个缺省的轮询器了。

pollerd performs individual service polls by iterating through a specified set of poller monitor "plugins.

通过对轮询器监控程序“插件”的指定集合进行循环处理，pollerd对个别服务进行轮询。

Next, we create the poller daemon (pollerd) monitor plugin: the org.opennms.netmgt.poller.ClickMeterMonitor class.

接下来，创建轮询器守护程序（pollerd）监控程序插件：org.opennms.netmgt.poller.ClickMeterMonitor类。

And the fourth is the poller and exacter of fees;

第四种就是收取与敲诈费用者；

We configure one as a default poller for the entire Spring Integration configuration because it's easier than repeating it.

出于简单，我们为整个SpringIntegration配置一个默认的轮询器。