28 lines
855 B
Swift
28 lines
855 B
Swift
//
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// Copyright (c) 2018 Open Whisper Systems. All rights reserved.
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//
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import Foundation
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@objc
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public class SSKIncrementingIdFinder: NSObject {
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@objc
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public static let collectionName = "IncrementingIdCollection"
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@objc
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public class func previousId(key: String, transaction: YapDatabaseReadTransaction) -> UInt64 {
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let previousId: UInt64 = transaction.object(forKey: key, inCollection: collectionName) as? UInt64 ?? 0
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return previousId
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}
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@objc
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public class func nextId(key: String, transaction: YapDatabaseReadWriteTransaction) -> UInt64 {
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let previousId: UInt64 = transaction.object(forKey: key, inCollection: collectionName) as? UInt64 ?? 0
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let nextId: UInt64 = previousId + 1
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transaction.setObject(nextId, forKey: key, inCollection: collectionName)
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return nextId
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}
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}
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