<s>
A	O
deployment	B-Language
descriptor	I-Language
(	O
DD	O
)	O
refers	O
to	O
a	O
configuration	B-Protocol
file	I-Protocol
for	O
an	O
artifact	O
that	O
is	O
deployed	O
to	O
some	O
container/engine	O
.	O
</s>
<s>
In	O
the	O
Java	B-Language
Platform	I-Language
,	I-Language
Enterprise	I-Language
Edition	I-Language
,	O
a	O
deployment	B-Language
descriptor	I-Language
describes	O
how	O
a	O
component	O
,	O
module	O
or	O
application	O
(	O
such	O
as	O
a	O
web	B-Application
application	I-Application
or	O
enterprise	B-Application
application	I-Application
)	O
should	O
be	O
deployed	O
.	O
</s>
<s>
It	O
directs	O
a	O
deployment	O
tool	O
to	O
deploy	O
a	O
module	O
or	O
application	O
with	O
specific	O
container	B-Language
options	O
,	O
security	O
settings	O
and	O
describes	O
specific	O
configuration	O
requirements	O
.	O
</s>
<s>
XML	B-Protocol
is	O
used	O
for	O
the	O
syntax	O
of	O
these	O
deployment	B-Language
descriptor	I-Language
files	O
.	O
</s>
<s>
For	O
web	B-Application
applications	I-Application
,	O
the	O
deployment	B-Language
descriptor	I-Language
must	O
be	O
called	O
web.xml	B-Language
and	O
must	O
reside	O
in	O
the	O
WEB-INF	O
directory	O
in	O
the	O
web	B-Application
application	I-Application
root	O
.	O
</s>
<s>
For	O
Java	B-Language
EE	I-Language
applications	O
,	O
the	O
deployment	B-Language
descriptor	I-Language
must	O
be	O
named	O
application.xml	O
and	O
must	O
be	O
placed	O
directly	O
in	O
the	O
META-INF	O
directory	O
at	O
the	O
top	O
level	O
of	O
the	O
application	O
.ear	B-Language
file	I-Language
.	O
</s>
<s>
In	O
Java	B-Language
EE	I-Language
,	O
there	O
are	O
two	O
types	O
of	O
deployment	B-Language
descriptors	I-Language
:	O
"	O
Java	B-Language
EE	I-Language
deployment	B-Language
descriptors	I-Language
"	O
and	O
"	O
runtime	O
deployment	B-Language
descriptors	I-Language
"	O
.	O
</s>
<s>
The	O
Java	B-Language
EE	I-Language
deployment	B-Language
descriptors	I-Language
are	O
defined	O
by	O
the	O
language	O
specification	O
,	O
whereas	O
the	O
runtime	O
descriptors	O
are	O
defined	O
by	O
the	O
vendor	O
of	O
each	O
container	B-Language
implementation	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
web.xml	B-Language
file	O
is	O
a	O
standard	O
Java	B-Language
EE	I-Language
deployment	B-Language
descriptor	I-Language
,	O
specified	O
in	O
the	B-Application
Java	I-Application
Servlet	I-Application
specification	O
,	O
but	O
the	O
sun-web.xml	O
file	O
contains	O
configuration	O
data	O
specific	O
to	O
the	O
Sun	B-Language
GlassFish	I-Language
Enterprise	I-Language
Server	I-Language
implementation	O
.	O
</s>
