<s>
Google	B-Language
Web	I-Language
Toolkit	I-Language
(	O
GWT	O
)	O
,	O
or	O
GWT	O
Web	O
Toolkit	O
,	O
is	O
an	O
open-source	B-Application
set	O
of	O
tools	B-Application
that	O
allows	O
web	B-Operating_System
developers	I-Operating_System
to	O
create	O
and	O
maintain	O
JavaScript	B-Language
front-end	B-Architecture
applications	O
in	O
Java	B-Language
.	O
</s>
<s>
It	O
is	O
licensed	O
under	O
Apache	B-Application
License	I-Application
2.0	I-Application
.	O
</s>
<s>
GWT	O
emphasizes	O
reusable	B-Application
approaches	O
to	O
everyday	O
web	O
development	O
tasks	O
,	O
namely	O
asynchronous	B-Operating_System
remote	I-Operating_System
procedure	I-Operating_System
calls	I-Operating_System
,	O
history	O
management	O
,	O
bookmarking	O
,	O
UI	B-Application
abstraction	O
,	O
internationalization	B-General_Concept
,	O
and	O
cross-browser	B-Architecture
portability	O
.	O
</s>
<s>
Google	B-Application
announced	O
GWT	O
at	O
the	O
JavaOne	O
conference	O
in	O
2006	O
.	O
</s>
<s>
In	O
August	O
2010	O
,	O
Google	B-Application
acquired	O
Instantiations	O
,	O
a	O
company	O
known	O
for	O
focusing	O
on	O
Eclipse	B-Application
Java	I-Application
developer	O
tools	B-Application
,	O
including	O
GWT	O
Designer	O
,	O
which	O
is	O
now	O
bundled	O
with	O
Google	B-Application
Plugin	I-Application
for	I-Application
Eclipse	I-Application
.	O
</s>
<s>
In	O
2011	O
with	O
the	O
introduction	O
of	O
the	O
Dart	B-Language
programming	I-Language
language	I-Language
,	O
Google	B-Application
reassured	O
the	O
GWT	O
community	O
that	O
GWT	O
would	O
continue	O
to	O
be	O
supported	O
for	O
the	O
foreseeable	O
future	O
but	O
also	O
hinted	O
at	O
a	O
possible	O
rapprochement	O
between	O
the	O
two	O
Google	B-Application
approaches	O
to	O
"	O
structured	O
web	O
programming	O
"	O
.	O
</s>
<s>
They	O
've	O
also	O
admitted	O
,	O
however	O
,	O
that	O
several	O
of	O
the	O
engineers	O
previously	O
working	O
on	O
GWT	O
are	O
now	O
working	O
on	O
Dart	B-Language
.	O
</s>
<s>
In	O
2012	O
at	O
their	O
annual	O
I/O	O
conference	O
,	O
Google	B-Application
announced	O
that	O
GWT	O
would	O
be	O
transformed	O
from	O
a	O
Google	B-Application
project	O
to	O
a	O
fully	O
open-sourced	O
project	O
.	O
</s>
<s>
In	O
July	O
2013	O
,	O
Google	B-Application
posted	O
on	O
its	O
GWT	O
blog	O
that	O
the	O
transformation	O
to	O
an	O
open-source	B-Application
project	O
was	O
complete	O
.	O
</s>
<s>
Using	O
GWT	O
,	O
developers	O
can	O
develop	O
and	O
debug	O
Ajax	B-General_Concept
applications	O
in	O
the	O
Java	B-Language
language	I-Language
using	O
the	O
Java	B-Language
development	B-Application
tools	I-Application
of	O
their	O
choice	O
.	O
</s>
<s>
When	O
the	O
application	O
is	O
deployed	O
,	O
the	O
GWT	O
cross-compiler	O
translates	O
the	O
Java	B-Language
application	O
to	O
standalone	O
JavaScript	B-Language
files	O
that	O
are	O
optionally	O
obfuscated	O
and	O
deeply	O
optimized	O
.	O
</s>
<s>
When	O
needed	O
,	O
JavaScript	B-Language
can	O
also	O
be	O
embedded	O
directly	O
into	O
Java	B-Language
code	I-Language
using	O
Java	B-Language
comments	O
.	O
</s>
<s>
GWT	O
does	O
not	O
revolve	O
only	O
around	O
user	B-Application
interface	I-Application
programming	O
;	O
it	O
is	O
a	O
broad	O
set	O
of	O
tools	B-Application
for	O
building	O
high-performance	O
client-side	O
JavaScript	B-Language
functionality	O
.	O
</s>
<s>
Development	O
mode	O
(	O
formerly	O
Hosted	O
mode	O
)	O
:	O
The	O
application	O
is	O
run	O
as	O
Java	B-Language
bytecode	O
within	O
the	O
Java	B-Language
Virtual	I-Language
Machine	I-Language
(	O
JVM	B-Language
)	O
.	O
</s>
<s>
Production	O
mode	O
(	O
formerly	O
Web	O
mode	O
)	O
:	O
The	O
application	O
is	O
run	O
as	O
pure	O
JavaScript	B-Language
and	O
HTML	O
,	O
compiled	O
from	O
the	O
Java	B-Language
source	O
.	O
</s>
<s>
Several	O
open-source	B-Application
plugins	B-Application
are	O
available	O
for	O
making	O
GWT	O
development	O
easier	O
with	O
other	O
IDEs	B-Application
,	O
including	O
GWT4NB	O
for	O
NetBeans	B-Application
,	O
Cypal	O
Studio	O
for	O
GWT	O
(	O
an	O
Eclipse	B-Application
plugin	B-Application
)	O
,	O
and	O
GWT	O
Developer	O
for	O
JDeveloper	B-Language
.	O
</s>
<s>
The	B-Application
Google	I-Application
Plugin	B-Application
for	O
Eclipse	B-Application
handles	O
most	O
GWT-related	O
tasks	O
in	O
the	O
IDE	O
,	O
including	O
creating	O
projects	O
,	O
invoking	O
the	O
GWT	O
compiler	O
,	O
creating	O
GWT	O
launch	O
configurations	O
,	O
validation	O
,	O
and	O
syntax	O
highlighting	O
.	O
</s>
<s>
Translates	O
the	O
Java	B-Language
programming	I-Language
language	I-Language
to	O
the	O
JavaScript	B-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
Allows	O
the	O
developers	O
to	O
run	O
and	O
execute	O
GWT	O
applications	O
in	O
development	O
mode	O
(	O
the	O
app	O
runs	O
as	O
Java	B-Language
in	O
the	O
JVM	B-Language
without	O
compiling	O
to	O
JavaScript	B-Language
)	O
.	O
</s>
<s>
Development	O
mode	O
is	O
supported	O
by	O
using	O
a	O
native-code	O
plugin	B-Application
called	O
the	B-Application
Google	I-Application
Web	O
Toolkit	O
Developer	O
Plugin	B-Application
for	O
many	O
popular	O
browsers	O
.	O
</s>
<s>
JavaScript	B-Language
implementations	O
of	O
the	O
commonly	O
used	O
classes	O
in	O
the	O
Java	B-Language
standard	O
class	O
library	O
(	O
such	O
as	O
most	O
of	O
the	O
java.lang	O
package	O
classes	O
and	O
a	O
subset	O
of	O
the	O
java.util	O
package	O
classes	O
)	O
.	O
</s>
<s>
Dynamic	O
and	O
reusable	B-Application
UI	B-Application
components	O
:	O
programmers	O
can	O
use	O
pre-designed	O
classes	O
to	O
implement	O
otherwise	O
time-consuming	O
dynamic	O
behaviors	O
,	O
such	O
as	O
drag-and-drop	O
or	O
sophisticated	O
visual	O
tree	O
structures	O
.	O
</s>
<s>
GWT	O
handles	O
some	O
cross-browser	B-Architecture
issues	O
for	O
the	O
developer	O
.	O
</s>
<s>
The	O
developers	O
can	O
mix	O
handwritten	O
JavaScript	B-Language
in	O
the	O
Java	B-Language
source	I-Language
code	I-Language
using	O
the	O
JavaScript	B-Language
Native	O
Interface	O
(	O
JSNI	B-Language
)	O
.	O
</s>
<s>
Support	O
for	O
using	O
Google	B-Application
APIs	B-Application
in	O
GWT	O
applications	O
(	O
initially	O
,	O
support	O
for	O
Google	B-Application
Gears	I-Application
)	O
.	O
</s>
<s>
The	O
developers	O
can	O
design	O
and	O
develop	O
their	O
applications	O
in	O
a	O
pure	O
object-oriented	O
fashion	O
since	O
they	O
're	O
using	O
Java	B-Language
(	O
instead	O
of	O
JavaScript	B-Language
)	O
.	O
</s>
<s>
Common	O
JavaScript	B-Language
errors	O
,	O
such	O
as	O
typos	O
and	O
type	O
mismatches	O
,	O
are	O
caught	O
at	O
compile	O
time	O
.	O
</s>
<s>
The	O
JavaScript	B-Language
that	O
the	O
GWT	O
compiler	O
generates	O
can	O
be	O
tailored	O
to	O
be	O
either	O
unobfuscated	O
(	O
Source-Mapped	O
or	O
Source-Code	O
)	O
and	O
easier	O
to	O
understand	O
or	O
obfuscated	O
and	O
compressed	O
.	O
</s>
<s>
A	O
number	O
of	O
libraries	O
are	O
available	O
for	O
GWT	O
,	O
by	O
Google	B-Application
and	O
third	O
parties	O
.	O
</s>
<s>
As	O
of	O
version	O
2.4	O
(	O
September	O
2011	O
)	O
,	O
Google	B-Language
Web	I-Language
Toolkit	I-Language
offers	B-Application
several	O
widgets	O
and	O
panels	O
.	O
</s>
<s>
GWT	O
uses	O
or	O
supports	O
Java	B-Language
,	O
Apache	B-Language
Tomcat	I-Language
(	O
or	O
similar	O
web	O
container	O
)	O
,	O
Eclipse	B-Application
IDE	I-Application
,	O
Internet	B-Application
Explorer	I-Application
,	O
and	O
internationalization	B-General_Concept
and	I-General_Concept
localization	I-General_Concept
.	O
</s>
<s>
Java-based	O
GWT	O
rich	B-Application
web	I-Application
applications	I-Application
can	O
be	O
tested	O
using	O
JUnit	B-Language
testing	O
framework	O
and	O
code	O
coverage	O
tools	B-Application
.	O
</s>
<s>
Google	B-Application
has	O
noted	O
that	O
some	O
of	O
its	O
products	O
are	O
GWT-based	O
:	O
Blogger	B-Application
,	O
AdWords	B-Application
,	O
Flights	O
,	O
Wallet	B-Application
,	O
Offers	B-Application
,	O
Groups	B-Application
,	O
Inbox	B-Protocol
.	O
</s>
<s>
On	O
December	O
8	O
,	O
2009	O
,	O
Google	B-Application
launched	O
Google	B-Language
Web	I-Language
Toolkit	I-Language
2.0	O
with	O
Speed	O
Tracer	O
.	O
</s>
<s>
Version	O
2.0	O
of	O
GWT	O
offers	B-Application
a	O
number	O
of	O
new	O
features	O
,	O
including	O
:	O
</s>
<s>
With	O
version	O
2.0	O
,	O
hosted	O
mode	O
,	O
renamed	O
"	O
development	O
mode	O
"	O
,	O
allows	O
using	O
any	O
(	O
supported	O
)	O
browser	O
to	O
view	O
the	O
page	O
being	O
debugged	O
through	O
the	O
use	O
of	O
a	O
browser	O
plugin	B-Application
.	O
</s>
<s>
The	O
plugin	B-Application
communicates	O
with	O
the	O
development	O
mode	O
shell	O
using	O
TCP/IP	O
,	O
which	O
allows	O
cross-platform	O
debugging	O
(	O
for	O
example	O
,	O
debugging	O
in	O
Internet	B-Application
Explorer	I-Application
on	O
Windows	B-Application
from	O
a	O
development	O
mode	O
shell	O
running	O
on	O
a	O
Linux	B-Application
machine	O
)	O
.	O
</s>
<s>
Code	O
splitting	O
:	O
with	O
the	O
developer	O
providing	O
"	O
split	O
points	O
"	O
in	O
the	O
source	O
code	O
,	O
the	O
GWT	O
compiler	O
can	O
split	O
the	O
JavaScript	B-Language
code	O
into	O
several	O
small	O
chunks	O
instead	O
of	O
one	O
big	O
download	O
.	O
</s>
<s>
Declarative	O
User	B-Application
Interface	I-Application
:	O
using	O
an	O
XML	O
format	O
,	O
the	O
new	O
feature	O
known	O
as	O
UiBinder	O
allows	O
the	O
creation	O
of	O
user	B-Application
interfaces	I-Application
through	O
declaration	O
rather	O
than	O
code	O
.	O
</s>
<s>
This	O
allows	O
a	O
clean	O
separation	O
of	O
UI	B-Application
construction	O
and	O
behavior	O
implementation	O
.	O
</s>
<s>
As	O
a	O
general	O
framework	O
for	O
making	O
web	O
apps	O
,	O
Google	B-Language
Web	I-Language
Toolkit	I-Language
is	O
also	O
capable	O
of	O
being	O
used	O
as	O
a	O
framework	O
for	O
creating	O
mobile	O
and	O
tablet	O
apps	O
,	O
either	O
by	O
making	O
the	O
needed	O
widgets	O
and	O
animations	O
from	O
scratch	O
or	O
by	O
using	O
one	O
of	O
the	O
mobile	O
frameworks	O
for	O
GWT	O
.	O
</s>
