Class ScyllaTrie.SynchronizedScyllaTrie

Thread-safe wrapper around ScyllaTrie that serialises all operations through a single monitor lock, making them safe for concurrent access from multiple threads. Obtain an instance via AsSynchronized(object) or Synchronized(object).

Inheritance
object
ScyllaTrie.SynchronizedScyllaTrie
Implements
Inherited Members
Namespace: Scylla.Core.Structures
Assembly: ScyllaCore.dll
Syntax
public sealed class ScyllaTrie.SynchronizedScyllaTrie : IScyllaTrie, IScyllaCollection
Remarks

All methods delegate to the wrapped ScyllaTrie while holding the internal lock. For multi-step atomic sequences (e.g. check-then-act), lock on SyncRoot externally:

lock (wrapper.SyncRoot)
{
    if (!wrapper.Contains("cmd"))
        wrapper.TryAdd("cmd");
}

Constructors

SynchronizedScyllaTrie(ScyllaTrie, object)

Initializes a new synchronized wrapper around the specified unsynchronized trie.

Declaration
public SynchronizedScyllaTrie(ScyllaTrie inner, object syncRoot)
Parameters
Type Name Description
ScyllaTrie inner

The ScyllaTrie to wrap. Must not be null. The wrapper takes a reference to this instance; the caller must not modify the trie directly after wrapping unless using the same syncRoot.
object syncRoot

An optional external lock object to synchronize on. When null, the wrapper allocates a private object as its lock. Supply a custom sync root to coordinate locking with other synchronized collections or operations.
Exceptions
Type Condition
ArgumentNullException

Thrown when inner is null.

Properties

Capabilities

Gets the capability flags supported by the wrapped trie. Cached at wrapper construction time; reads do not require locking.

Declaration
public ScyllaCollectionCapabilities Capabilities { get; }
Property Value
Type Description
ScyllaCollectionCapabilities

Count

Gets the number of keys currently stored in the wrapped trie, acquired under the internal lock.

Declaration
public int Count { get; }
Property Value
Type Description
int

EdgeCapacity

Gets the current number of edge slots allocated in the wrapped trie's internal edge array. Delegates to EdgeCapacity under the internal lock.

Declaration
public int EdgeCapacity { get; }
Property Value
Type Description
int

IsEmpty

Gets a value indicating whether the wrapped trie contains no keys, acquired under the internal lock.

Declaration
public bool IsEmpty { get; }
Property Value
Type Description
bool

IsFixedCapacity

Gets a value indicating whether the wrapped trie is operating in fixed-capacity mode. This value is cached at wrapper construction time and does not require locking.

Declaration
public bool IsFixedCapacity { get; }
Property Value
Type Description
bool

NodeCapacity

Gets the current number of node slots allocated in the wrapped trie's internal node array. Delegates to NodeCapacity under the internal lock.

Declaration
public int NodeCapacity { get; }
Property Value
Type Description
int

SyncRoot

Gets the monitor object used to synchronize all operations on this wrapper. Use this object with lock to perform atomic multi-step sequences against the trie.

Declaration
public object SyncRoot { get; }
Property Value
Type Description
object

ThreadSafety

Gets the thread-safety guarantee for this wrapper instance. Always Synchronized.

Declaration
public ScyllaCollectionThreadSafety ThreadSafety { get; }
Property Value
Type Description
ScyllaCollectionThreadSafety

Methods

Clear()

Removes all keys from the wrapped trie under the internal lock. See Clear() for full semantics.

Declaration
public void Clear()

Contains(string)

Determines whether the exact key exists in the wrapped trie. Thread-safe. See Contains(string) for full parameter and return documentation.

Declaration
public bool Contains(string key)
Parameters
Type Name Description
string key

The key to search for. Must not be null.
Returns
Type Description
bool

true if the key exists; false otherwise.

ContainsPrefix(string)

Determines whether the wrapped trie contains at least one key starting with prefix. Thread-safe. See ContainsPrefix(string) for full documentation.

Declaration
public bool ContainsPrefix(string prefix)
Parameters
Type Name Description
string prefix

The prefix to test. Must not be null.
Returns
Type Description
bool

true if any stored key starts with prefix; false otherwise.

CopyMatches(string, Span<string>)

Copies all keys that start with prefix in ascending lexicographic order into destination under the internal lock. Thread-safe. See CopyMatches(string, Span<string>) for full documentation.

Declaration
public int CopyMatches(string prefix, Span<string> destination)
Parameters
Type Name Description
string prefix

The prefix to filter by. Must not be null.
Span<string> destination

The target span to write matching keys into.
Returns
Type Description
int

The number of keys written.

CopyMatches(string, string[], int)

Copies all keys that start with prefix in ascending lexicographic order into destination starting at destinationIndex, under the internal lock. Thread-safe. See CopyMatches(string, string[], int) for full documentation.

Declaration
public int CopyMatches(string prefix, string[] destination, int destinationIndex)
Parameters
Type Name Description
string prefix

The prefix to filter by. Must not be null.
string[] destination

The target array to write matching keys into. Must not be null.
int destinationIndex

Zero-based start index within the array.
Returns
Type Description
int

The number of keys written.

CopyTo(Span<string>)

Copies all stored keys in ascending lexicographic order into destination under the internal lock. Thread-safe. See CopyTo(Span<string>) for full documentation.

Declaration
public int CopyTo(Span<string> destination)
Parameters
Type Name Description
Span<string> destination

The target span to write keys into.
Returns
Type Description
int

The number of keys written.

CopyTo(string[], int)

Copies all stored keys in ascending lexicographic order into destination starting at destinationIndex, under the internal lock. Thread-safe. See CopyTo(string[], int) for full documentation.

Declaration
public int CopyTo(string[] destination, int destinationIndex)
Parameters
Type Name Description
string[] destination

The target array to write keys into. Must not be null.
int destinationIndex

Zero-based start index within the array.
Returns
Type Description
int

The number of keys written.

TryAdd(string)

Attempts to insert the specified key into the wrapped trie under the internal lock. Thread-safe. See TryAdd(string) for full documentation.

Declaration
public bool TryAdd(string key)
Parameters
Type Name Description
string key

The key to add. Must not be null.
Returns
Type Description
bool

true if the key was inserted; false if the key already exists or the trie is at fixed capacity.

TryRemove(string)

Attempts to remove the specified key from the wrapped trie under the internal lock. Thread-safe. See TryRemove(string) for full documentation.

Declaration
public bool TryRemove(string key)
Parameters
Type Name Description
string key

The key to remove. Must not be null.
Returns
Type Description
bool

true if the key was found and removed; false otherwise.

Implements

Extension Methods