<s>
A	O
Technology	B-Language
Compatibility	I-Language
Kit	I-Language
(	O
TCK	O
)	O
is	O
a	O
suite	O
of	O
tests	O
that	O
at	O
least	O
nominally	O
checks	O
a	O
particular	O
alleged	O
implementation	O
of	O
a	O
Java	B-Language
Specification	I-Language
Request	I-Language
(	O
JSR	O
)	O
for	O
compliance	O
.	O
</s>
<s>
It	O
is	O
one	O
of	O
the	O
three	O
required	O
pieces	O
for	O
a	O
ratified	O
JSR	O
in	O
the	O
Java	B-Language
Community	I-Language
Process	I-Language
,	O
which	O
are	O
:	O
</s>
<s>
This	O
decoupling	O
enables	O
TCKs	O
to	O
be	O
used	O
to	O
test	O
virtual	O
machines	O
on	O
devices	O
such	O
as	O
CLDC	B-Language
mobile	O
phones	O
which	O
do	O
not	O
have	O
the	O
power	O
to	O
run	O
the	O
full	O
TCK	O
host	O
application	O
.	O
</s>
<s>
(	O
For	O
example	O
,	O
listing	O
all	O
the	O
supported	O
media	O
formats	O
and	O
associated	O
optional	O
controls	O
for	O
JSR135	B-Language
)	O
.	O
</s>
<s>
There	O
's	O
no	O
alternative	O
but	O
to	O
do	O
much	O
real-world	O
testing	O
to	O
address	O
these	O
shortcomings	O
,	O
although	O
additional	O
test	O
suites	O
such	O
as	O
JDTS	B-Language
may	O
help	O
.	O
</s>
<s>
The	O
Technology	B-Language
Compatibility	I-Language
Kit	I-Language
for	O
a	O
particular	O
Java	B-Language
platform	I-Language
is	O
called	O
Java	O
Compatibility	O
Kit	O
(	O
JCK	O
)	O
.	O
</s>
<s>
It	O
is	O
an	O
extensive	O
test	O
suite	O
used	O
by	O
Oracle	B-Application
and	O
licensees	O
to	O
ensure	O
compatible	O
implementations	O
of	O
the	O
platform	O
.	O
</s>
<s>
However	O
,	O
since	O
the	O
release	O
of	O
OpenJDK	B-Language
,	O
a	O
specific	O
license	O
allows	O
running	O
the	O
JCK	O
in	O
the	O
OpenJDK	B-Language
context	O
,	O
that	O
is	O
for	O
any	O
GPL	B-License
implementation	O
deriving	O
substantially	O
from	O
OpenJDK	B-Language
.	O
</s>
<s>
The	O
OpenJDK	B-Language
Community	O
TCK	O
License	O
Agreement	O
v	O
2.0	O
has	O
been	O
published	O
for	O
the	O
Java	B-Language
SE	I-Language
7	O
Specification	O
since	O
December	O
2011	O
.	O
</s>
<s>
The	O
JavaTest	B-Language
harness	I-Language
tool	O
is	O
today	O
the	O
most	O
common	O
unit	O
testing	O
framework	O
used	O
to	O
verify	O
the	O
implementation	O
compliance	O
.	O
</s>
<s>
However	O
,	O
some	O
specifications	O
are	O
also	O
using	O
JUnit	B-Language
or	O
TestNG	B-Language
.	O
</s>
<s>
Subsequent	O
to	O
Sun	O
's	O
release	O
of	O
OpenJDK	B-Language
,	O
Sun	O
released	O
a	O
specific	O
license	O
to	O
permit	O
running	O
the	O
TCK	O
in	O
the	O
OpenJDK	B-Language
context	O
for	O
any	O
GPL	B-License
implementation	O
deriving	O
substantially	O
from	O
OpenJDK	B-Language
.	O
</s>
<s>
This	O
requirement	O
denies	O
the	O
Apache	B-Application
Harmony	I-Application
project	O
an	O
Apache	O
License-compatible	O
right	O
to	O
use	O
the	O
TCK	O
.	O
</s>
<s>
On	O
November	O
9	O
,	O
2010	O
,	O
the	O
Apache	O
Software	O
Foundation	O
threatened	O
to	O
withdraw	O
from	O
the	O
Java	B-Language
Community	I-Language
Process	I-Language
if	O
they	O
were	O
not	O
granted	O
a	O
TCK	O
license	O
for	O
Harmony	O
without	O
additional	O
restrictions	O
.	O
</s>
