root / trunk / Pithos.Core / Agents / SnapshotDifferencer.cs @ 422c9598
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// ----------------------------------------------------------------------- |
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// <copyright file="SnapshotDifferencer.cs" company="Microsoft"> |
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// TODO: Update copyright text. |
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// </copyright> |
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// ----------------------------------------------------------------------- |
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using Pithos.Interfaces; |
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namespace Pithos.Core.Agents |
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{ |
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using System; |
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using System.Collections.Generic; |
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using System.Linq; |
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using System.Text; |
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|
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/// <summary> |
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/// TODO: Update summary. |
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/// </summary> |
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public class SnapshotDifferencer |
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{ |
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private IEnumerable<ObjectInfo> _previous; |
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private IEnumerable<ObjectInfo> _current; |
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private static ObjectInfo[] _empty = new ObjectInfo[0]; |
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private ObjectInfoComparer _comparer = new ObjectInfoComparer(); |
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|
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public SnapshotDifferencer() |
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{ |
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_previous = new List<ObjectInfo>(); |
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_current= new List<ObjectInfo>(); |
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} |
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public SnapshotDifferencer(IEnumerable<ObjectInfo> previous,IEnumerable<ObjectInfo> current ) |
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{ |
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_previous = previous ?? new List<ObjectInfo>(); |
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_current= current ?? new List<ObjectInfo>(); |
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} |
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public SnapshotDifferencer Post(IEnumerable<ObjectInfo> list) |
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{ |
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_previous = _current; |
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_current = list ?? new List<ObjectInfo>(); |
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return this; |
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} |
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|
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public IEnumerable<ObjectInfo> Deleted |
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{ |
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get { return _previous.Except(_current,_comparer); } |
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} |
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public IEnumerable<ObjectInfo> Created |
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{ |
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get { return _current.Except(_previous,_comparer); } |
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} |
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public IEnumerable<ObjectInfo> Changed |
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{ |
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get |
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{ |
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var changes = from newItem in _current |
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let oldItem=_previous.FirstOrDefault(old=>_comparer.Equals(old,newItem)) |
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where oldItem !=null && |
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newItem.Hash != oldItem.Hash |
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select newItem; |
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return changes; |
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} |
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} |
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public IEnumerable<ObjectInfo> Unchanged |
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{ |
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get |
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{ |
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var unChanged = from newItem in _current |
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let oldItem = _previous.FirstOrDefault(old => _comparer.Equals(old, newItem)) |
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where oldItem != null && |
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newItem.Hash == oldItem.Hash |
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select newItem; |
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return unChanged; |
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} |
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} |
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} |
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} |