com.google.gwt.core.client
Class GWT

java.lang.Object
  com.google.gwt.core.client.GWT

public final class GWT
extends java.lang.Object

Supports core functionality that in some cases requires direct support from the compiler and runtime systems such as runtime type information and deferred binding.

Nested Class Summary

static interface

GWT.UncaughtExceptionHandler This interface is used to catch exceptions at the "top level" just before they escape to the browser.

Constructor Summary

GWT()

Method Summary

static java.lang.Object	create(java.lang.Class classLiteral) Instantiates a class via deferred binding.
static java.lang.String	getHostPageBaseURL() Gets the URL prefix of the hosting page, useful for prepending to relative paths of resources which may be relative to the host page.
static java.lang.String	getModuleBaseURL() Gets the URL prefix of the module which should be prepended to URLs that are intended to be module-relative, such as RPC entry points and files in the module's public path.
static java.lang.String	getModuleName() Gets the name of the running module.
static java.lang.String	getTypeName(java.lang.Object o) Gets the class name of the specified object, as would be returned by o.getClass().getName().
static GWT.UncaughtExceptionHandler	getUncaughtExceptionHandler() Returns the currently active uncaughtExceptionHandler.
static boolean	isScript() Determines whether or not the running program is script or bytecode.
static void	log(java.lang.String message, java.lang.Throwable e) Logs a message to the development shell logger in hosted mode.
static void	setUncaughtExceptionHandler(GWT.UncaughtExceptionHandler handler) Sets a custom uncaught exception handler.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GWT

public GWT()

Method Detail

create

public static java.lang.Object create(java.lang.Class classLiteral)

Instantiates a class via deferred binding.

The argument to create(Class) must be a class literal because the web mode compiler must be able to statically determine the requested type at compile-time. This can be tricky because using a Class variable may appear to work correctly in hosted mode.

Parameters:

classLiteral - a class literal specifying the base class to be instantiated

Returns:

the new instance, which must be typecast to the requested class.

getHostPageBaseURL

public static java.lang.String getHostPageBaseURL()

Gets the URL prefix of the hosting page, useful for prepending to relative paths of resources which may be relative to the host page. Typically, you should use getModuleBaseURL() unless you have a specific reason to load a resource relative to the host page.

Returns:

if non-empty, the base URL is guaranteed to end with a slash

getModuleBaseURL

public static java.lang.String getModuleBaseURL()

Gets the URL prefix of the module which should be prepended to URLs that are intended to be module-relative, such as RPC entry points and files in the module's public path.

Returns:

if non-empty, the base URL is guaranteed to end with a slash

getModuleName

public static java.lang.String getModuleName()

Gets the name of the running module.

getTypeName

public static java.lang.String getTypeName(java.lang.Object o)

Gets the class name of the specified object, as would be returned by o.getClass().getName().

Parameters:

o - the object whose class name is being sought, or null

Returns:

the class name of the specified object, or null if o is null

getUncaughtExceptionHandler

public static GWT.UncaughtExceptionHandler getUncaughtExceptionHandler()

Returns the currently active uncaughtExceptionHandler. "Top level" methods that dispatch events from the browser into user code must call this method on entry to get the active handler. If the active handler is null, the entry point must allow exceptions to escape into the browser. If the handler is non-null, exceptions must be caught and routed to the handler. See the source code for DOM.dispatchEvent() for an example of how to handle this correctly.

Returns:

the currently active handler, or null if no handler is active.

isScript

public static boolean isScript()

Determines whether or not the running program is script or bytecode.

log

public static void log(java.lang.String message,
                       java.lang.Throwable e)

Logs a message to the development shell logger in hosted mode. Calls are optimized out in web mode.

setUncaughtExceptionHandler

public static void setUncaughtExceptionHandler(GWT.UncaughtExceptionHandler handler)

Sets a custom uncaught exception handler. See getUncaughtExceptionHandler() for details.

Parameters:

handler - the handler that should be called when an exception is about to escape to the browser, or null to clear the handler and allow exceptions to escape.