|
CSP for Java (JCSP) 1.0-rc4 |
||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Object | +--jcsp.lang.Guard | +--jcsp.lang.AltingChannelInput | +--jcsp.lang.AltingChannel | +--jcsp.lang.Any2OneChannel
This implements a any-to-one object channel, safe for use by many writers and one reader.
The reading process may ALT
on this channel.
The writing process is committed (i.e. it may not back off).
The default semantics of the channel is that of CSP -- i.e. it is zero-buffered and fully synchronised. The reading process must wait for a matching writer and vice-versa.
However, the static create method allows the user to create
a channel with a plug-in driver conforming to the
jcsp.util.ChannelDataStore
interface. This allows a variety of different channel semantics to be
introduced -- including buffered channels of user-defined capacity
(including infinite), overwriting channels (with various overwriting
policies) etc..
Standard examples are given in the jcsp.util package, but
careful users may write their own.
Other static create methods allows the user to create fully initialised arrays of channels, including plug-ins if required.
Alternative
,
One2OneChannel
,
One2AnyChannel
,
Any2AnyChannel
,
ChannelDataStore
, Serialized FormConstructor Summary | |
Any2OneChannel()
Constructs a new Any2OneChannel with a ZeroBuffer ChannelDataStore. |
|
Any2OneChannel(ChannelDataStore data)
Deprecated. Use Any2AnyChannel.create (ChannelDataStore). |
Method Summary | |
static Any2OneChannel |
create(ChannelDataStore store)
Creates a Any2OneChannel using the specified ChannelDataStore. |
static Any2OneChannel[] |
create(int n)
Creates an array of Any2OneChannels. |
static Any2OneChannel[] |
create(int n,
ChannelDataStore store)
Creates an array of Any2OneChannel using the specified ChannelDataStore. |
boolean |
pending()
Returns whether there is data pending on this channel. |
Object |
read()
Reads an Object from the Channel. |
void |
write(Object value)
Writes an Object to the Channel. |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Constructor Detail |
public Any2OneChannel()
public Any2OneChannel(ChannelDataStore data)
data
- The ChannelDataStore used to store the data for the ChannelMethod Detail |
public Object read()
public void write(Object value)
value
- The object to write to the Channel.public boolean pending()
Note: if there is, it won't go away until you read it. But if there isn't, there may be some by the time you check the result of this method.
This method is provided for convenience. Its functionality can be provided by Pri Alting the channel against a SKIP guard, although at greater run-time and syntactic cost. For example, the following code fragment:
if (c.pending ()) { Object x = c.read (); ... do something with x } else ( ... do something else }is equivalent to:
if (c_pending.priSelect () == 0) { Object x = c.read (); ... do something with x } else ( ... do something else }where earlier would have had to have been declared:
final Alternative c_pending = new Alternative (new Guard[] {c, new Skip ()});
pending
in class AltingChannelInput
public static Any2OneChannel[] create(int n)
n
- the number of channels to create in the arraypublic static Any2OneChannel create(ChannelDataStore store)
public static Any2OneChannel[] create(int n, ChannelDataStore store)
n
- the number of channels to create in the array
|
CSP for Java (JCSP) 1.0-rc4 |
||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |