org.apache.cassandra.net

Interface ResourceLimits.Limit

All Known Implementing Classes:

ResourceLimits.Concurrent

Enclosing class:

ResourceLimits

public static interface ResourceLimits.Limit

Represents permits to utilise a resource and ways to allocate and release them. Two implementations are currently provided: 1. ResourceLimits.Concurrent, for shared limits, which is thread-safe; 2. Basic, for limits that are not shared between threads, is not thread-safe.

Method Summary

Modifier and Type	Method and Description
void	allocate(long amount) Allocates an amount independent of permits available from this limit.
long	limit()
ResourceLimits.Outcome	release(long amount)
long	remaining()
boolean	tryAllocate(long amount) Attempts to allocate an amount of permits from this limit.
long	using()

Method Detail

limit

long limit()

Returns:

total amount of permits represented by this ResourceLimits.Limit - the capacity

remaining

long remaining()

Returns:

remaining, unallocated permit amount

using

long using()

Returns:

amount of permits currently in use

tryAllocate

boolean tryAllocate(long amount)

Attempts to allocate an amount of permits from this limit. If allocated, MUST eventually be released back with release(long).

Returns:

true if the allocation was successful, false otherwise

allocate

void allocate(long amount)

Allocates an amount independent of permits available from this limit. MUST eventually be released back with release(long).

release

ResourceLimits.Outcome release(long amount)

Parameters:

amount - return the amount of permits back to this limit

Returns:

ABOVE_LIMIT if there aren't enough permits available even after the release, or BELOW_LIMIT if there are enough permits available after the releaese.