Model Listeners

For this one you'll have to define a portal.property file typically stored at,

/docroot/WEB-INF/src/portal.property

并告诉liferay-hook.xml它的位置.以下是上述示例，

And tell liferay-hook.xml its location. The following is an example for the above,

<portal-properties>portal.properties</portal-properties>

例如，如果您想听用户中的更改，则可以在属性中编写

if you want to listen to changes in User, for example, you would write in the property,

value.object.listener.com.liferay.portal.model.User=com.my.example.UserListener;

采用以下格式，

value.object.listener.[class-to-listen]=[my-listener-class]

您的课程应该实现com.liferay.portal.model.BaseModelListener.

在这里您可以收听添加，更新，删除和其他一些事件.

Here you can listen to events such as Add, Update, Remove, and a few others.

这里有一个类似的故事，在liferay-hook.xml的<hook />元素中添加

A similar story here, in liferay-hook.xml in the <hook /> element add

<service>
    <service-type>com.liferay.portal.service.UserService</service-type>
    <service-impl>my.example.service.UserServiceImpl</service-impl>
</service>

在这里，您的实现应为特定服务扩展正确的包装器类.例如，对于上面的示例，

Here your implementation should extend the correct wrapper class for a particular service. For the example above, for instance, is

com.liferay.portal.service.UserServiceWrapper;

您现在应该能够覆盖UserService的所有公共方法，例如updateUser(..).

You should now be able to overwrite all the public methods for the UserService like updateUser(..).

以与扩展服务非常相似的方式，定义<hook />

In very similar fashion as extending services, define the elements for <hook />

<struts-action>
    <struts-action-path>/message_boards/view</struts-action-path>
    <struts-action-impl>my.example.action.SampleViewAction</struts-action-impl>
</struts-action>

您需要扩展

com.liferay.portal.kernel.struts.BaseStrutsAction

，您将有权访问该请求并可以执行自定义操作.与自定义JSP结合使用时，该功能非常强大.

and you'll have access to the request and can perform a custom action. Which is very powerful in conjunction with custom JSPs.

请确保检查与您使用的Liferay版本的兼容性.

Be sure to check compatibility with the version of Liferay you are using.

如果您需要更多控制权，则需要使用ext-plugin.

If you need even more control you would need to use the ext-plugin.