/
future.go
54 lines (47 loc) · 1.33 KB
/
future.go
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/*
* Copyright (c) 2008-2021, Hazelcast, Inc. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License")
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package cb
// Future holds a value computed in the future
// Futures are not re-usable
type Future interface {
// Result blocks until the future is complete
Result() (maybeResult interface{}, err error)
}
type FutureImpl struct {
resultCh chan interface{}
}
func NewFutureImpl() *FutureImpl {
return &FutureImpl{
resultCh: make(chan interface{}, 1),
}
}
func NewSucceededFuture(result interface{}) *FutureImpl {
fut := NewFutureImpl()
fut.resultCh <- result
return fut
}
func NewFailedFuture(err error) *FutureImpl {
return NewSucceededFuture(err)
}
func (f FutureImpl) Result() (interface{}, error) {
result := <-f.resultCh
switch v := result.(type) {
case error:
return nil, v
default:
return v, nil
}
}