pool.go

// Copyright (c) 2016 Uber Technologies, Inc.
//
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// furnished to do so, subject to the following conditions:
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// The above copyright notice and this permission notice shall be included in
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package policy

import "github.com/m3db/m3x/pool"

// PoliciesPool provides a pool for variable-sized policy slices.
type PoliciesPool interface {
	// Init initializes the pool.
	Init()

	// Get provides a policy slice from the pool.
	Get(capacity int) []Policy

	// Put returns a policy slice to the pool.
	Put(value []Policy)
}

type policiesPool struct {
	pool pool.BucketizedObjectPool
}

// NewPoliciesPool creates a new policies pool.
func NewPoliciesPool(sizes []pool.Bucket, opts pool.ObjectPoolOptions) PoliciesPool {
	return &policiesPool{pool: pool.NewBucketizedObjectPool(sizes, opts)}
}

func (p *policiesPool) Init() {
	p.pool.Init(func(capacity int) interface{} {
		return make([]Policy, 0, capacity)
	})
}

func (p *policiesPool) Get(capacity int) []Policy {
	return p.pool.Get(capacity).([]Policy)
}

func (p *policiesPool) Put(value []Policy) {
	value = value[:0]
	p.pool.Put(value, cap(value))
}