# Package org.zkoss.zk.ui.util

- Interface Summary
  Interface | Description
  --- | ---
  AggregationListener | A listener to gather some non-predefined listeners
  Callback<T> | A callback interface to execute in some circumstance.
  CharsetFinder | Represents a class that decides the character set based on the content type and the real content.
  ComponentActivationListener | Used to notify an object stored in a component, when the session is going to be deactivated or has been activated.
  ComponentCloneListener | Used to notify an object stored in a component, when the component is cloned.
  ComponentSerializationListener | Used to notify an object stored in a component, when the component is going to be serialized or has been deserialized.
  Composer<T extends Component> | Represents a composer to initialize a component (or a component of tree) when ZK loader is composing a component.
  ComposerExt<T extends Component> | An addition interface implemented with `Composer` to provide more control.
  Condition | A condition to test with.
  ConfigParser | A configuration parser is an application-specific parser to parse the configurations in zk.xml.
  CspProvider | Used to provide Content Security Policy (CSP) headers and nonces.
  DesktopActivationListener | Used to notify an object stored in a desktop, when the session is going to be deactivated or has been activated.
  DesktopCleanup | Used to clean up a desktop.
  DesktopInit | Used to initialize a desktop when it is created.
  DesktopRecycle | Used to recycle the desktop (`Desktop`).
  DesktopSerializationListener | Used to notify an object stored in a desktop, when the desktop is going to be serialized or has been deserialized.
  EventInterceptor | The event interceptor used to intercept the processing of events.
  ExecutionCleanup | Used to clean up an execution.
  ExecutionInit | Used to initialize an execution when it is created.
  ExecutionMonitor | An application-level listener to know when an execution is activated, deactivated, or waiting for activation.
  ForEach | Used to denote a collection of elements.
  ForEachStatus | Represents the runtime information of each iteration caused by `ForEach`.
  FullComposer | A decorative interface used with `Composer` (and/or `ComposerExt`) to indicate that it requires the full control.
  Initiator | Implemented by an initiator that will be invoked if it is specified in the init directive.
  InitiatorExt | An extra interface that can be implemented with `Initiator` to have the better control.
  Monitor | A listener to monitor the status of ZK engine.
  PageActivationListener | Used to notify an object stored in a page, when the session is going to be deactivated or has been activated.
  PageSerializationListener | Used to notify an object stored in a page, when the page is going to be serialized or has been deserialized.
  PerformanceMeter | An application-level listener to measure the performance of the processing of client requests.
  RequestInterceptor | Used to intercept the requests for the ZK Loader and Update Engine.
  SessionActivationListener | Used to notify an object stored in a session, when the session is going to be deactivated or has been activated.
  SessionCleanup | Used to clean up a session.
  SessionInit | Used to initialize a session when it is created.
  SessionSerializationListener | Used to notify an object stored in a session, when the session is going to be serialized or has been deserialized.
  Template | Represents a UI template that is used to create components.
  TemplateCtrl | An addition interface to `Template` that is used for implementation or tools.
  ThemeProvider | Used to replace the theme defined in the language definitions (lang.xml and lang-addon.xml), `ThemeURIHandler` and the configuration (the `theme-uri` elements in web.xml).
  ThemeURIHandler | Used to add theme uri dynamically without extending any ThemeProvider.
  ThemeURIModifier | ThemeURIModifier is used to restrict developer's operation on the theme uri list.
  UiLifeCycle | Used to intercept the life cycle of UI, such as `Component` being attached.
  URIInterceptor | Used to intercept the loading of ZUML pages associated with the specified URI.
  WebAppCleanup | Used to initialize a ZK application when it about to be destroyed.
  WebAppInit | Used to initialize a ZK application when it is created.

- Class Summary
  Class | Description
  --- | ---
  Clients | Utilities to send `AuResponse` to the client.
  Composition | Composition manager that compose the given components into a whole page per the "insert" components and "define" components annotations.
  ConditionImpl | An utility to simplify the implementation of `Condition`.
  Configuration | The ZK configuration.
  ConventionWires | Utilities to wire variables by name conventions.
  DataHandlerInfo | A data handler info for `Configuration` to use.
  ForEachImpl | An implementation of `ForEach`.
  GenericAutowireComposer<T extends Component> | A skeletal composer that you can extend and write intuitive onXxx event handler methods with "auto-wired" accessible variable objects such as implicit objects, components, and external resolvable variables in a ZK zuml page.
  GenericComposer<T extends Component> | A skeletal composer that you can extend and write intuitive onXxx event handler methods; this class will registers onXxx events to the supervised component automatically.
  GenericForwardComposer<T extends Component> | A skeletal composer that you can extend and write intuitive onXxx$myid event handler methods with auto event forwarding and "auto-wired" accessible variable objects such as embedded objects, components, and external resolvable variables in a ZK zuml page; this class will add forward condition to the myid source component and forward source onXxx event received by the source myid component to the target onXxx$myid event (as defined in this composer) of the supervised target component; of course it will also registers onXxx$myid events to the supervised component and wire all accessible variable objects to this composer by calling setXxx() method or set xxx field value directly per the variable name.
  GenericInitiator | A skeletal implementation that provides does-nothing for all methods, such that the deriving class needs only to implement the required method.
  Notification | Utilities to send Notification to the client.
  SimpleThemeURIModifier | A simple implementation of `ThemeURIModifier`.
  Statistic | An implementation of `Monitor` to accumulate statistic data in memory.
  ThemeProvider.Aide | Utilities to help the implementation of `ThemeProvider` to manipulate the URI such that it is able to use a different URI for a different theme.
  URIInfo | Represents an URI and how to use the URI.