filesbox/app/filesbox_ios/FilesBox/Pods/Realm/include/RLMThreadSafeReference.h
2023-09-21 10:53:23 +08:00

107 lines
4.1 KiB
Objective-C

////////////////////////////////////////////////////////////////////////////
//
// Copyright 2016 Realm Inc.
//
// 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.
//
////////////////////////////////////////////////////////////////////////////
#import <Foundation/Foundation.h>
@class RLMRealm;
NS_ASSUME_NONNULL_BEGIN
/**
Objects of types which conform to `RLMThreadConfined` can be managed by a Realm, which will make
them bound to a thread-specific `RLMRealm` instance. Managed objects must be explicitly exported
and imported to be passed between threads.
Managed instances of objects conforming to this protocol can be converted to a thread-safe
reference for transport between threads by passing to the
`+[RLMThreadSafeReference referenceWithThreadConfined:]` constructor.
Note that only types defined by Realm can meaningfully conform to this protocol, and defining new
classes which attempt to conform to it will not make them work with `RLMThreadSafeReference`.
*/
@protocol RLMThreadConfined <NSObject>
// Conformance to the `RLMThreadConfined_Private` protocol will be enforced at runtime.
/**
The Realm which manages the object, or `nil` if the object is unmanaged.
Unmanaged objects are not confined to a thread and cannot be passed to methods expecting a
`RLMThreadConfined` object.
*/
@property (nonatomic, readonly, nullable) RLMRealm *realm;
/// Indicates if the object can no longer be accessed because it is now invalid.
@property (nonatomic, readonly, getter = isInvalidated) BOOL invalidated;
@end
/**
An object intended to be passed between threads containing a thread-safe reference to its
thread-confined object.
To resolve a thread-safe reference on a target Realm on a different thread, pass to
`-[RLMRealm resolveThreadSafeReference:]`.
@warning A `RLMThreadSafeReference` object must be resolved at most once.
Failing to resolve a `RLMThreadSafeReference` will result in the source version of the
Realm being pinned until the reference is deallocated.
@note Prefer short-lived `RLMThreadSafeReference`s as the data for the version of the source Realm
will be retained until all references have been resolved or deallocated.
@see `RLMThreadConfined`
@see `-[RLMRealm resolveThreadSafeReference:]`
*/
@interface RLMThreadSafeReference<__covariant Confined : id<RLMThreadConfined>> : NSObject
/**
Create a thread-safe reference to the thread-confined object.
@param threadConfined The thread-confined object to create a thread-safe reference to.
@note You may continue to use and access the thread-confined object after passing it to this
constructor.
*/
+ (instancetype)referenceWithThreadConfined:(Confined)threadConfined;
/**
Indicates if the reference can no longer be resolved because an attempt to resolve it has already
occurred. References can only be resolved once.
*/
@property (nonatomic, readonly, getter = isInvalidated) BOOL invalidated;
#pragma mark - Unavailable Methods
/**
`-[RLMThreadSafeReference init]` is not available because `RLMThreadSafeReference` cannot be
created directly. `RLMThreadSafeReference` instances must be obtained by calling
`-[RLMRealm resolveThreadSafeReference:]`.
*/
- (instancetype)init __attribute__((unavailable("RLMThreadSafeReference cannot be created directly")));
/**
`-[RLMThreadSafeReference new]` is not available because `RLMThreadSafeReference` cannot be
created directly. `RLMThreadSafeReference` instances must be obtained by calling
`-[RLMRealm resolveThreadSafeReference:]`.
*/
+ (instancetype)new __attribute__((unavailable("RLMThreadSafeReference cannot be created directly")));
@end
NS_ASSUME_NONNULL_END