Redesigned Cache<TKey,TValue>, Added KeyedCache<TKey, TValue>

master
Harald Wolff 2022-07-01 21:12:51 +02:00
parent 61a010c666
commit 8baf7c9f49
4 changed files with 243 additions and 66 deletions

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@ -0,0 +1,46 @@
using System;
using System.Threading;
using NUnit.Framework;
namespace ln.collections.test
{
[TestFixture]
public class CacheTests
{
[Test]
public void Test_Cache_1()
{
Cache<int, string> cache = new Cache<int, string>(TimeSpan.FromSeconds(1));
for (int n = 0; n < 10; n++)
cache.Add(n, n.ToString());
cache.Cleanup();
Assert.AreEqual(10, cache.Count);
Thread.Sleep(1000);
cache.Cleanup();
Assert.AreEqual(0, cache.Count);
for (int n = 0; n < 10; n++)
{
cache.Add(n, n.ToString());
Thread.Sleep(90);
}
Thread.Sleep(10);
for (int n = 10; n > 0; n--)
{
cache.Cleanup();
Assert.AreEqual(n, cache.Count);
Thread.Sleep(90);
}
Assert.Pass();
}
}
}

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@ -4,7 +4,9 @@
<IsPackable>false</IsPackable>
<TargetFrameworks>net5.0</TargetFrameworks>
<TargetFrameworks>net5.0;net6.0</TargetFrameworks>
<LangVersion>default</LangVersion>
</PropertyGroup>
<ItemGroup>

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@ -1,95 +1,223 @@
using System;
using System.Collections.Generic;
using System.Linq;
namespace ln.collections
{
public class Cache<K,V>
public class Cache<TKey, TValue>
{
public int Count => values.Count;
public TimeSpan DefaultLifeTime { get; set; }
private readonly Dictionary<TKey, Entry> _cache = new Dictionary<TKey, Entry>();
BTree<K, V> values;
BTree<K, LinkedListItem<K>> itemTree;
LinkedList<K> items = new LinkedList<K>();
int maxCacheSize = 4096;
public Cache(TimeSpan defaultLifeTime)
{
DefaultLifeTime = defaultLifeTime;
}
public Cache()
: this(TimeSpan.FromMinutes(10))
{
values = new BTree<K, V>();
itemTree = new BTree<K, LinkedListItem<K>>();
}
public Cache(Comparison<K> compare)
{
values = new BTree<K, V>(compare);
itemTree = new BTree<K, LinkedListItem<K>>(compare);
}
public int MaxCacheSize
public void CopyTo(KeyValuePair<TKey, TValue>[] array, int arrayIndex)
{
get => maxCacheSize;
set {
maxCacheSize = value;
while (maxCacheSize < values.Count)
lock (this)
{
foreach (var cacheEntry in _cache)
{
Forget();
if (cacheEntry.Value.IsValid)
array[arrayIndex++] = new KeyValuePair<TKey, TValue>(cacheEntry.Key, cacheEntry.Value.Value);
}
}
}
public void Clear()
{
values.Clear();
itemTree.Clear();
items.Clear();
}
public bool TryGet(K key,out V value)
{
return values.TryGet(key, out value);
}
public void Forget()
{
lock (this)
public int Count {
get
{
Forget(items.FirstItem);
}
}
public void Forget(K key)
{
lock (this)
{
if (itemTree.TryGet(key,out LinkedListItem<K> item))
Forget(item);
lock (this) { return _cache.Count; }
}
}
private void Forget(LinkedListItem<K> item)
{
if (item == null)
return;
values.Remove(item.Value);
itemTree.Remove(item.Value);
items.Remove(item);
}
public void Ensure(K key,V value)
public bool IsReadOnly => false;
public void Clear() { lock (this) _cache.Clear(); }
public void Cleanup()
{
lock (this)
{
if (!itemTree.TryGet(key, out LinkedListItem<K> item))
foreach (var key in _cache.Keys.ToArray())
{
item = new LinkedListItem<K>(key);
values.Add(key,value);
if (!_cache[key].IsValid)
_cache.Remove(key);
}
Ensure(item);
}
}
private void Ensure(LinkedListItem<K> item)
public bool Contains(KeyValuePair<TKey, TValue> item) { lock (this) return TryGetValue(item.Key, out TValue value) && object.Equals(item.Value, value); }
public void Add(KeyValuePair<TKey, TValue> item) => Add(item.Key, item.Value);
public bool Remove(KeyValuePair<TKey, TValue> item)
{
if (!item.IsLinked)
itemTree.Add(item.Value, item);
items.Add(item);
lock (this)
{
if (_cache.TryGetValue(item.Key, out Entry entry) && object.Equals(item.Value, entry.Value))
{
_cache.Remove(item.Key);
return entry.IsValid;
}
return false;
}
}
public void Add(TKey key, TValue value)
{
lock (this)
{
_cache.Add(key, new Entry(this, value));
}
}
public bool ContainsKey(TKey key)
{
lock (this) return _cache.ContainsKey(key) && _cache[key].IsValid;
}
public bool Remove(TKey key)
{
lock (this) return _cache.Remove(key);
}
public bool TryGetValue(TKey key, out TValue value)
{
lock (this)
{
if (_cache.TryGetValue(key, out Entry entry))
{
if (entry.IsValid)
{
value = entry.Value;
return true;
}
else
{
_cache.Remove(key);
}
}
}
value = default(TValue);
return false;
}
public TValue this[TKey key]
{
get
{
lock (this)
{
if (TryGetValue(key, out TValue value))
return value;
}
throw new KeyNotFoundException();
}
set
{
lock (this)
{
if (_cache.TryGetValue(key, out Entry entry))
entry.Reset(value);
else
_cache.Add(key, new Entry(this, value));
}
}
}
public bool ReValidate(TKey key)
{
lock (this)
{
if (_cache.TryGetValue(key, out Entry entry))
{
if (entry.IsValid)
{
entry.UpdateTimestamp();
return true;
}
else
{
_cache.Remove(key);
}
}
return false;
}
}
public TValue GetOrCreate(TKey key, Func<TKey, TValue> factory)
{
lock (this)
{
if (!TryGetValue(key, out TValue value))
{
value = factory(key);
Add(key, value);
}
return value;
}
}
class Entry
{
private Cache<TKey, TValue> _cache;
public DateTime TimeOut { get; private set; }
public TValue Value { get; private set; }
public Entry(Cache<TKey,TValue> cache, TValue value)
{
_cache = cache;
Value = value;
UpdateTimestamp();
}
public void UpdateTimestamp() => UpdateTimestamp(_cache.DefaultLifeTime);
public void UpdateTimestamp(TimeSpan lifeTime) => TimeOut = DateTime.Now + lifeTime;
public bool IsValid => TimeOut > DateTime.Now;
public void Reset(TValue newValue)
{
Value = newValue;
UpdateTimestamp();
}
}
}
public abstract class KeyedCache<TKey, TValue> : Cache<TKey, TValue>
{
protected KeyedCache()
{
}
protected KeyedCache(TimeSpan defaultTimeOut)
:base(defaultTimeOut)
{
}
protected abstract TKey GetKey(TValue value);
public void Add(TValue value) => Add(GetKey(value), value);
public bool RemoveValue(TValue value)
{
TKey key = GetKey(value);
lock (this)
{
if (TryGetValue(key, out TValue cachedValue) && object.Equals(cachedValue, value))
{
return Remove(key);
}
}
return false;
}
}

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@ -7,8 +7,9 @@
<Company>l--n.de</Company>
<AssemblyVersion>0.0.1.1</AssemblyVersion>
<FileVersion>0.0.1.1</FileVersion>
<PackageVersion>0.1.7</PackageVersion>
<TargetFramework>net5.0</TargetFramework>
<PackageVersion>0.2.0</PackageVersion>
<TargetFrameworks>net5.0;net6.0</TargetFrameworks>
<LangVersion>default</LangVersion>
</PropertyGroup>
<ItemGroup>