<s>
Apache	B-Language
Tapestry	I-Language
is	O
an	O
open-source	B-Application
component-oriented	O
Java	B-Language
web	B-Application
application	I-Application
framework	I-Application
conceptually	O
similar	O
to	O
JavaServer	B-Language
Faces	I-Language
and	O
Apache	B-Language
Wicket	I-Language
.	O
</s>
<s>
Tapestry	B-Language
was	O
created	O
by	O
Howard	O
Lewis	O
Ship	O
,	O
and	O
was	O
adopted	O
by	O
the	O
Apache	O
Software	O
Foundation	O
as	O
a	O
top-level	O
project	O
in	O
2006	O
.	O
</s>
<s>
Tapestry	B-Language
emphasizes	O
simplicity	O
,	O
ease	O
of	O
use	O
,	O
and	O
developer	O
productivity	O
.	O
</s>
<s>
It	O
adheres	O
to	O
the	O
Convention	B-Application
over	I-Application
Configuration	I-Application
paradigm	O
,	O
eliminating	O
almost	O
all	O
XML	O
configuration	O
.	O
</s>
<s>
Tapestry	B-Language
uses	O
a	O
modular	O
approach	O
to	O
web	O
development	O
by	O
having	O
a	O
strong	O
binding	B-General_Concept
between	O
each	O
user	B-Application
interface	I-Application
component	O
(	O
object	O
)	O
on	O
the	O
web	O
page	O
and	O
its	O
corresponding	O
Java	B-Language
class	O
.	O
</s>
<s>
This	O
component-based	O
architecture	O
borrows	O
many	O
ideas	O
from	O
WebObjects	B-Language
.	O
</s>
<s>
Live	O
Class	O
Reloading	O
Tapestry	B-Language
monitors	O
the	O
file	O
system	O
for	O
changes	O
to	O
Java	B-Language
page	O
classes	O
,	O
component	O
classes	O
,	O
service	O
implementation	O
classes	O
,	O
HTML	O
templates	O
and	O
component	O
property	O
files	O
,	O
and	O
it	O
hot-swaps	O
the	O
changes	O
into	O
the	O
running	O
application	O
without	O
requiring	O
a	O
restart	O
.	O
</s>
<s>
Convention	B-Application
over	I-Application
configuration	I-Application
Tapestry	B-Language
uses	O
naming	O
conventions	O
and	O
annotations	O
,	O
rather	O
than	O
XML	O
,	O
to	O
configure	O
the	O
application	O
.	O
</s>
<s>
Spare	O
use	O
of	O
HTTPSession	O
By	O
making	O
minimal	O
use	O
of	O
the	O
HTTPSession	O
,	O
Tapestry	B-Language
is	O
designed	O
to	O
be	O
highly	O
efficient	O
in	O
a	O
clustered	O
,	O
session-replicated	O
environment	O
.	O
</s>
<s>
Post/Redirect/Get	B-Application
Most	O
form	O
submissions	O
follow	O
the	O
Post/Redirect/Get	B-Application
(	O
PRG	O
)	O
pattern	O
,	O
which	O
reduces	O
multiple	O
form	O
submission	O
accidents	O
and	O
makes	O
URLs	O
friendlier	O
and	O
more	O
bookmarkable	O
,	O
along	O
with	O
enabling	O
the	O
browser	O
Back	O
and	O
Refresh	O
buttons	O
to	O
operate	O
normally	O
.	O
</s>
<s>
Inversion	B-Language
of	I-Language
Control	I-Language
(	O
IoC	O
)	O
Tapestry	B-Language
is	O
built	O
on	O
a	O
lightweight	O
Inversion	B-Language
of	I-Language
Control	I-Language
layer	O
with	O
similarities	O
to	O
Google	B-Application
Guice	I-Application
,	O
but	O
designed	O
to	O
make	O
nearly	O
all	O
aspects	O
of	O
Tapestry	B-Language
's	O
behavior	O
configurable	O
and	O
replaceable	O
.	O
</s>
<s>
A	O
minimal	O
,	O
templated	O
Tapestry	B-Language
application	O
needs	O
only	O
three	O
files	O
:	O
</s>
<s>
Tapestry	B-Language
templates	O
can	O
contain	O
any	O
well-formed	O
(	O
X	O
)	O
HTML	O
markup	O
.	O
</s>
<s>
The	O
servlet	B-Application
application	O
Deployment	B-Language
Descriptor	I-Language
,	O
which	O
installs	O
Tapestry	B-Language
as	O
a	O
servlet	B-Application
filter	O
.	O
</s>
<s>
Tapestry	B-Language
uses	O
bytecode	O
manipulation	O
to	O
transform	O
page	O
and	O
component	O
classes	O
at	O
runtime	O
.	O
</s>
<s>
This	O
approach	O
allows	O
the	O
page	O
and	O
component	O
classes	O
to	O
be	O
written	O
as	O
simple	O
POJOs	B-Language
,	O
with	O
a	O
few	O
naming	O
conventions	O
and	O
annotations	O
potentially	O
triggering	O
substantial	O
additional	O
behavior	O
at	O
class	O
load	O
time	O
.	O
</s>
<s>
Tapestry	B-Language
versions	O
5.0	O
,	O
5.1	O
and	O
5.2	O
used	O
the	O
Javassist	B-Language
bytecode	O
manipulation	O
library	O
.	O
</s>
<s>
Subsequent	O
versions	O
replaced	O
Javassist	B-Language
with	O
a	O
new	O
bytecode	O
manipulation	O
layer	O
called	O
Plastic	O
that	O
is	O
based	O
on	O
ObjectWeb	B-Language
ASM	I-Language
.	O
</s>
<s>
Tapestry	B-Language
5	O
versions	O
up	O
through	O
5.3	O
bundled	O
the	O
Prototype	B-Language
and	O
script.aculo.us	B-Language
JavaScript	B-Application
frameworks	I-Application
,	O
along	O
with	O
a	O
Tapestry-specific	O
library	O
,	O
so	O
as	O
to	O
support	O
Ajax	O
operations	O
as	O
first-class	O
citizens	O
.	O
</s>
<s>
Third	O
party	O
modules	O
are	O
available	O
to	O
integrate	O
jQuery	O
instead	O
of	O
,	O
or	O
in	O
addition	O
to	O
,	O
Prototype/Scriptaculous	O
.	O
</s>
<s>
Starting	O
with	O
version	O
5.4	O
,	O
Tapestry	B-Language
includes	O
a	O
new	O
JavaScript	O
layer	O
that	O
removes	O
built-in	O
components	O
 '	O
reliance	O
on	O
Prototype	B-Language
,	O
allowing	O
jQuery	O
or	O
another	O
JavaScript	B-Application
framework	I-Application
to	O
be	O
plugged	O
in	O
.	O
</s>
<s>
The	O
Tapestry	B-Language
project	O
documentation	O
cites	O
four	O
"	O
principles	O
"	O
that	O
govern	O
all	O
development	O
decisions	O
for	O
Tapestry	B-Language
,	O
starting	O
with	O
version	O
5	O
in	O
2008	O
:	O
</s>
<s>
Ensure	O
Backwards	O
Compatibility	O
—	O
The	O
Tapestry	B-Language
developers	O
are	O
reportedly	O
committed	O
to	O
ensuring	O
that	O
upgrading	O
to	O
the	O
latest	O
version	O
of	O
Tapestry	B-Language
is	O
always	O
easy	O
.	O
</s>
<s>
Tapestry	B-Language
has	O
been	O
criticized	O
as	O
not	O
being	O
backward-compatible	O
across	O
major	O
versions	O
,	O
especially	O
noted	O
in	O
the	O
transition	O
from	O
version	O
4	O
to	O
version	O
5	O
,	O
where	O
no	O
clean	O
migration	O
path	O
was	O
available	O
for	O
existing	O
applications	O
.	O
</s>
<s>
Project	O
team	O
members	O
have	O
acknowledged	O
this	O
as	O
a	O
major	O
problem	O
for	O
Tapestry	B-Language
's	O
users	O
in	O
the	O
past	O
,	O
and	O
backward	O
compatibility	O
was	O
made	O
a	O
major	O
design	O
goal	O
for	O
Tapestry	B-Language
going	O
forward	O
.	O
</s>
<s>
From	O
early	O
on	O
in	O
the	O
development	O
of	O
version	O
5	O
,	O
backward	O
compatibility	O
was	O
listed	O
as	O
one	O
of	O
Tapestry	B-Language
's	O
four	O
new	O
"	O
Core	O
Principles	O
"	O
,	O
and	O
two	O
of	O
the	O
other	O
three	O
were	O
intended	O
to	O
make	O
the	O
evolution	O
of	O
the	O
framework	O
possible	O
without	O
sacrificing	O
backward	O
compatibility	O
.	O
</s>
<s>
Project	O
team	O
members	O
claim	O
that	O
all	O
Tapestry	B-Language
releases	O
since	O
5.0	O
have	O
been	O
highly	O
backward	O
compatible	O
.	O
</s>
<s>
Early	O
criticisms	O
of	O
Tapestry	B-Language
5	O
also	O
mentioned	O
documentation	O
as	O
a	O
shortcoming	O
.	O
</s>
<s>
Since	O
version	O
5.0	O
,	O
Tapestry	B-Language
has	O
bundled	O
the	O
Prototype	B-Language
and	O
Scriptaculous	B-Language
JavaScript	O
libraries	O
.	O
</s>
<s>
Since	O
then	O
,	O
however	O
,	O
Prototype	B-Language
's	O
popularity	O
has	O
declined	O
,	O
and	O
jQuery	O
's	O
has	O
risen	O
dramatically	O
.	O
</s>
<s>
In	O
response	O
,	O
the	O
Tapestry	B-Language
community	O
developed	O
modules	O
that	O
allowed	O
jQuery	O
to	O
be	O
used	O
in	O
addition	O
to	O
,	O
or	O
instead	O
of	O
,	O
Prototype	B-Language
.	O
</s>
<s>
Meanwhile	O
,	O
the	O
current	O
version	O
of	O
Tapestry	B-Language
,	O
5.4	O
,	O
removes	O
the	O
dependency	O
on	O
Prototype	B-Language
entirely	O
,	O
replacing	O
it	O
with	O
a	O
compatibility	O
layer	O
into	O
which	O
either	O
jQuery	O
or	O
Prototype	B-Language
(	O
or	O
potentially	O
any	O
other	O
JavaScript	B-Application
framework	I-Application
)	O
can	O
be	O
plugged	O
.	O
</s>
<s>
According	O
to	O
Howard	O
Lewis	O
Ship	O
,	O
Tapestry	B-Language
was	O
initially	O
conceived	O
as	O
an	O
attempt	O
to	O
implement	O
in	O
Java	B-Language
some	O
of	O
the	O
general	O
concepts	O
and	O
approaches	O
found	O
in	O
WebObjects	B-Language
,	O
which	O
was	O
at	O
that	O
time	O
written	O
in	O
Objective-C	B-Language
and	O
closed-source	O
.	O
</s>
<s>
Apache	B-Language
Wicket	I-Language
was	O
developed	O
as	O
a	O
response	O
to	O
the	O
complexity	O
of	O
early	O
versions	O
of	O
Tapestry	B-Language
,	O
according	O
to	O
Wicket	B-Language
originator	O
Jonathan	O
Locke	O
.	O
</s>
<s>
Facelets	B-Language
,	O
the	O
default	O
view	O
technology	O
in	O
JavaServer	B-Language
Faces	I-Language
,	O
was	O
reportedly	O
inspired	O
by	O
early	O
versions	O
of	O
Tapestry	B-Language
,	O
as	O
an	O
attempt	O
to	O
fill	O
the	O
need	O
for	O
"	O
a	O
framework	O
like	O
Tapestry	B-Language
,	O
backed	O
by	O
JavaServer	B-Language
Faces	I-Language
as	O
the	O
industry	O
standard	O
"	O
.	O
</s>
<s>
Version	O
Date	O
Description	O
2000	O
Developed	O
by	O
Howard	O
Lewis	O
Ship	O
for	O
internal	O
use	O
2002-04	O
First	O
made	O
available	O
on	O
SourceForge	B-Application
under	O
the	O
GNU	B-Application
Lesser	I-Application
General	I-Application
Public	I-Application
License	I-Application
.	O
</s>
<s>
2006-01	O
Introduced	O
support	O
for	O
JDK	O
1.5	O
annotations	O
,	O
a	O
new	O
input	O
validation	O
subsystem	O
,	O
and	O
improved	O
error	O
reporting	O
2008-12	O
A	O
nearly	O
complete	O
rewrite	O
from	O
Tapestry	B-Language
4	O
,	O
introducing	O
a	O
new	O
POJO-based	O
component	O
model	O
emphasizing	O
convention	B-Application
over	I-Application
configuration	I-Application
,	O
and	O
replaced	O
Hivemind	O
with	O
a	O
new	O
no-XML	O
Inversion	B-Language
of	I-Language
Control	I-Language
layer	O
.	O
</s>
<s>
2009-04	O
Performance	O
and	O
memory	O
improvements	O
,	O
automatic	O
GZIP	O
compression	O
,	O
JavaScript	O
aggregation	O
,	O
but	O
remained	O
backwards	O
compatible	O
to	O
Tapestry	B-Language
5.0	O
.	O
</s>
<s>
2010-12	O
Added	O
JSR	B-Language
303	I-Language
Bean	I-Language
Validation	I-Language
.	O
</s>
<s>
New	O
JavaScript	O
layer	O
for	O
switchable	O
jQuery/Prototype	O
support	O
,	O
uses	O
Require.js	O
for	O
its	O
JavaScript	O
module	O
system	O
,	O
Twitter	B-Application
Bootstrap	I-Application
for	O
its	O
default	O
styling	O
.	O
</s>
<s>
Support	O
for	O
Java	B-Language
12	O
bytecode	O
,	O
Typescript	O
,	O
and	O
Bootstrap	B-Application
4	O
.	O
</s>
