使用 ResourceChangeListener AEM 6.3 处理事件答案

【问题标题】：Handling events using ResourceChangeListener AEM 6.3使用 ResourceChangeListener AEM 6.3 处理事件
【发布时间】：2018-02-10 13:29:29
【问题描述】：

有人可以帮助我理解如何使用 osgi R6 注释实现 ResourceChangeListener 和处理事件吗？我看到一个类似的帖子没有答案。AEM 6.3 - Creating Event handler using OSGi R6 annotations

【问题讨论】：

标签： annotations osgi aem addeventlistener

【解决方案1】：

下面的代码 sn-p 注册了一个带有 OSGI R6 注释的 ResourceChangeListener。内联的 cmets 有解释。

import java.util.List;
import org.apache.sling.api.resource.observation.ResourceChange;
import org.apache.sling.api.resource.observation.ResourceChangeListener;
import org.osgi.service.component.annotations.Component;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Component(
    service = ResourceChangeListener.class,
    property = {
        // filter the notifications by path in the repo. Can be array and supports globs
        ResourceChangeListener.PATHS+"="+"/content",
        //The type of change you want to listen to.
        //Possible values at https://sling.apache.org/apidocs/sling9/org/apache/sling/api/resource/observation/ResourceChange.ChangeType.html.
        ResourceChangeListener.CHANGES+"="+"ADDED",
        ResourceChangeListener.CHANGES+"="+"REMOVED",
        ResourceChangeListener.CHANGES+"="+"CHANGED"

        //PS: If you want to declare multiple values for a prop, you repeat it in OSGI R6 annotations.
        //https://stackoverflow.com/questions/41243873/osgi-r6-service-component-annotations-property-list#answer-41248826
    }
)
public class SampleResourceChangeListener implements ResourceChangeListener{ // Use ExternalResourceChangeListener to listen for changes that happen in a different node
  public static final Logger LOGGER = LoggerFactory.getLogger(SampleResourceChangeListener.class);

  //This method will be called with paths and types of change that occurred
  //The task in this should be fast. In case it takes more time, trigger a sling job from here.
  //The listener can be blacklisted if it's slow [it does for event handler, should be same for ResourceListener IMHO]
  @Override
  public void onChange(List<ResourceChange> list) {
    list.forEach((change) -> {
      LOGGER.info(change.getPath());
      LOGGER.info(change.getType().toString());
      //the methods to identify the property that changed are deprecated.
    });
  }
}

Sling 中的一些参考实现

【讨论】：

非常感谢。现在在添加一个节点时，我的监听器被调用了。由于我的路径指向 DAM 资产路径，因此将为所有子节点以及 jcr:content、演绎版（每个单独）调用此侦听器。如何仅针对父节点而不是子节点限制它。 ?
您只希望在节点类型 dam:Asset 或原始版本上触发它？
是的..我正在尝试同样的事情..它正在工作..再次感谢您的回复。
如果我需要单独配置 ResourceChangeListener.PATHS+"="+"/content"，我需要在此处进行哪些更改？我创建了这个：@ObjectClassDefinition(name="test Listener") public @interface TsetConfiguration { @AttributeDefinition(name = "Resource Path", description = "Resource path where the file is present", type = AttributeType.STRING) String getResourcepath( ) 默认“/内容”； }但是如何将它用作 ResourcePath 属性？
我猜你已经在activate方法中动态注册了资源变化监听器。查看 github.com/apache/sling-org-apache-sling-scripting-core/blob/… 中的 configureCache 方法。在使用新道具注册之前，请务必取消注册和现有的监听器