CollectionUtilities
using System;
using System.Collections.Generic;
using System.Text;
namespace Org.BouncyCastle.Utilities.Collections
{
public abstract class CollectionUtilities
{
public static void CollectMatches<T>(ICollection<T> matches, ISelector<T> selector, IEnumerable<IStore<T>> stores)
{
if (matches == null)
throw new ArgumentNullException("matches");
if (stores != null) {
foreach (IStore<T> store in stores) {
if (store != null) {
foreach (T item in store.EnumerateMatches(selector)) {
matches.Add(item);
}
}
}
}
}
public static IStore<T> CreateStore<T>(IEnumerable<T> contents)
{
return new StoreImpl<T>(contents);
}
public static T GetFirstOrNull<T>(IEnumerable<T> e) where T : class
{
if (e != null) {
using (IEnumerator<T> enumerator = e.GetEnumerator()) {
if (enumerator.MoveNext())
return enumerator.Current;
}
}
return null;
}
public static T GetValueOrKey<T>(IDictionary<T, T> d, T k)
{
if (!d.TryGetValue(k, out T value))
return k;
return value;
}
public static V GetValueOrNull<K, V>(IDictionary<K, V> d, K k) where V : class
{
if (!d.TryGetValue(k, out V value))
return null;
return value;
}
public static IEnumerable<T> Proxy<T>(IEnumerable<T> e)
{
return new EnumerableProxy<T>(e);
}
public static ICollection<T> ReadOnly<T>(ICollection<T> c)
{
return new ReadOnlyCollectionProxy<T>(c);
}
public static IDictionary<K, V> ReadOnly<K, V>(IDictionary<K, V> d)
{
return new ReadOnlyDictionaryProxy<K, V>(d);
}
public static IList<T> ReadOnly<T>(IList<T> l)
{
return new ReadOnlyListProxy<T>(l);
}
public static ISet<T> ReadOnly<T>(ISet<T> s)
{
return new ReadOnlySetProxy<T>(s);
}
public static bool Remove<K, V>(IDictionary<K, V> d, K k, out V v)
{
if (!d.TryGetValue(k, out v))
return false;
d.Remove(k);
return true;
}
public static T RequireNext<T>(IEnumerator<T> e)
{
if (!e.MoveNext())
throw new InvalidOperationException();
return e.Current;
}
public static string ToString<T>(IEnumerable<T> c)
{
IEnumerator<T> enumerator = c.GetEnumerator();
if (!enumerator.MoveNext())
return "[]";
StringBuilder stringBuilder = new StringBuilder("[");
stringBuilder.Append(enumerator.Current);
while (enumerator.MoveNext()) {
stringBuilder.Append(", ");
stringBuilder.Append(enumerator.Current);
}
stringBuilder.Append(']');
return stringBuilder.ToString();
}
}
}