# Package com.google.gwt.core.client

Fundamental classes used in client-side GWT code.

See: Description

- Interface Summary
  Interface | Description
  --- | ---
  AsyncProvider<T,F> | An object capable of providing an instance of type T asynchronously via `Callback`.
  Callback<T,F> | A callback for any asynchronous call that can result in success or failure.
  EntryPoint | Implement this interface to allow a class to act as a module entry point.
  GWT.UncaughtExceptionHandler | This interface is used to catch exceptions at the "top level" just before they escape to the browser.
  RunAsyncCallback | A callback meant to be used by `GWT.runAsync(RunAsyncCallback)`.
  Scheduler.RepeatingCommand | General-purpose Command interface for tasks that repeat.
  Scheduler.ScheduledCommand | General-purpose Command interface.

- Class Summary
  Class | Description
  --- | ---
  Duration | A utility class for measuring elapsed time.
  GWT | Supports core functionality that in some cases requires direct support from the compiler and runtime systems such as runtime type information and deferred binding.
  GWTBridge | When running in Development Mode, acts as a bridge from `GWT` into the Development Mode environment.
  JavaScriptObject | An opaque handle to a native JavaScript object.
  JsArray<T extends JavaScriptObject> | A simple wrapper around a homogeneous native array of `JavaScriptObject` values.
  JsArrayBoolean | A simple wrapper around a homogeneous native array of boolean values.
  JsArrayInteger | A simple wrapper around a homogeneous native array of integer values.
  JsArrayMixed | A simple wrapper around an heterogeneous native array of values.
  JsArrayNumber | A simple wrapper around a homogeneous native array of numeric values.
  JsArrayString | A simple wrapper around a homogeneous native array of string values.
  JsArrayUtils | Utility class for manipulating JS arrays.
  JsDate | A simple wrapper around a native JS Date object.
  JsonUtils | Provides JSON-related utility methods.
  Scheduler | This class provides low-level task scheduling primitives.
  ScriptInjector | Dynamically create a script tag and attach it to the DOM.
  ScriptInjector.FromString | Builder for directly injecting a script body into the DOM.
  ScriptInjector.FromUrl | Build an injection call for adding a script by URL.

- Enum Summary
  Enum | Description
  --- | ---
  CodeDownloadException.Reason | Reason codes for the interruption of code down load.

- Exception Summary
  Exception | Description
  --- | ---
  CodeDownloadException | Exception indicating an interruption while downloading resources.
  JavaScriptException | Any JavaScript exceptions occurring within JSNI methods are wrapped as this class when caught in Java code.

- Annotation Types Summary
  Annotation Type | Description
  --- | ---
  GwtScriptOnly | Deprecated since hosted/dev mode is deprecated and has no other uses.
  SingleJsoImpl | This annotation may be placed on an interface to declare the single JavaScriptObject type that implements the interface.
  SingleJsoImplName | This annotation may be placed on an interface to name the single JavaScriptObject type that implements the interface.
  UnsafeNativeLong | This annotation can be placed on a native method to allow it to directly access Java `long` values.

## Package com.google.gwt.core.client Description

Fundamental classes used in client-side GWT code. The classes in this package represent concepts fundamental to GWT, such as module entry points, and interfacing with JavaScript.