Module CountDownLatch

module CountDownLatch: sig .. end

Countdown synchronization.

type t = java'util'concurrent'CountDownLatch java_instance

The type of countdown latches, that are barrier-like synchronization entities.

val make : java_int -> t

make n returns a countdown latch waiting for n threads; see CountDownLatch(...) .
Raises Java_exception if n is negative

val await : t -> unit

Waits until the coutdown reaches zero, without countingdown; see await(...) .
Raises Java_exception if the thread is interrupted

val await_time : t -> java_long -> TimeUnit.t -> bool

await_time c t u is similar to await c, except that the current thread will at most wait for t (time value whose unit is u); see await(...) .
Raises Java_exception if the thread is interrupted

val count_down : t -> unit

Decrements the count, and then waits for the countdown to reach zero; see countDown(...) .

val get_count : t -> java_long

Returns the current count; see getCount(...) .

Null value

val null : t

The null value.

val is_null : t -> bool

is_null obj returns true iff obj is equal to null.

val is_not_null : t -> bool

is_not_null obj returns false iff obj is equal to null.

Miscellaneous

val wrap : t -> t option

wrap obj wraps the reference obj into an option type:

Some x if obj is not null;
None if obj is null.

val unwrap : t option -> t

unwrap obj unwraps the option obj into a bare reference:

Some x is mapped to x;
None is mapped to null.