1+ using System . Linq ;
2+ using NHibernate . Cfg . MappingSchema ;
3+ using NHibernate . Linq ;
4+ using NHibernate . Mapping . ByCode ;
5+ using NUnit . Framework ;
6+ using System . Collections . Generic ;
7+ using System ;
8+
9+ namespace NHibernate . Test . NHSpecificTest . NH3050
10+ {
11+ /// <summary>
12+ /// Fixture using 'by code' mappings
13+ /// </summary>
14+ /// <remarks>
15+ /// This fixture is identical to <see cref="Fixture" /> except the <see cref="Entity" /> mapping is performed
16+ /// by code in the GetMappings method, and does not require the <c>Mappings.hbm.xml</c> file. Use this approach
17+ /// if you prefer.
18+ /// </remarks>
19+ [ TestFixture ]
20+ public class FixtureByCode : TestCaseMappingByCode
21+ {
22+ protected override HbmMapping GetMappings ( )
23+ {
24+ var mapper = new ModelMapper ( ) ;
25+ mapper . Class < Entity > ( rc =>
26+ {
27+ rc . Id ( x => x . Id , m => m . Generator ( Generators . GuidComb ) ) ;
28+ rc . Property ( x => x . Name ) ;
29+ } ) ;
30+
31+ return mapper . CompileMappingForAllExplicitlyAddedEntities ( ) ;
32+ }
33+
34+ protected override void OnSetUp ( )
35+ {
36+ using ( ISession session = OpenSession ( ) )
37+ using ( ITransaction transaction = session . BeginTransaction ( ) )
38+ {
39+ var e1 = new Entity { Name = "Bob" } ;
40+ session . Save ( e1 ) ;
41+
42+ var e2 = new Entity { Name = "Sally" } ;
43+ session . Save ( e2 ) ;
44+
45+ session . Flush ( ) ;
46+ transaction . Commit ( ) ;
47+ }
48+ }
49+
50+ protected override void OnTearDown ( )
51+ {
52+ using ( ISession session = OpenSession ( ) )
53+ using ( ITransaction transaction = session . BeginTransaction ( ) )
54+ {
55+ session . Delete ( "from System.Object" ) ;
56+
57+ session . Flush ( ) ;
58+ transaction . Commit ( ) ;
59+ }
60+ }
61+
62+ [ Test ]
63+ public void NH3050_Reproduction ( )
64+ {
65+ //firstly to make things simpler, we set the query plan cache size to 1
66+ Assert . IsTrue ( TrySetQueryPlanCacheSize ( Sfi , 1 ) ) ;
67+
68+ using ( ISession session = OpenSession ( ) )
69+ using ( session . BeginTransaction ( ) )
70+ {
71+ var names = new List < string > ( ) { "Bob" } ;
72+ var query = from e in session . Query < Entity > ( )
73+ where names . Contains ( e . Name )
74+ select e ;
75+
76+ //create a future, which will prepare a linq query plan and add it to the cache (NhLinqExpression)
77+ var future = query . ToFuture ( ) ;
78+
79+ //we need enough unique queries (different to our main query here) to fill the plan cache so that our previous plan is evicted
80+ //in this case we only need one as we have limited the cache size to 1
81+ ( from e in session . Query < Entity > ( )
82+ where e . Name == ""
83+ select e ) . ToList ( ) ;
84+
85+ //garbage collection runs so that the query plan for our future which is a weak reference now in the plan cache is collected.
86+ GC . Collect ( ) ;
87+
88+ //execute future which creates an ExpandedQueryExpression and adds it to the plan cache (generates the same cache plan key as the NhLinqExpression)
89+ future . ToList ( ) ;
90+
91+ //execute original query again which will look for a NhLinqExpression in the plan cache but because it has already been evicted
92+ //and because the ExpandedQueryExpression generates the same cache key, the ExpandedQueryExpression is returned and
93+ //an exception is thrown as it tries to cast to a NhLinqExpression.
94+ query . ToList ( ) ;
95+ }
96+ }
97+
98+ /// <summary>
99+ /// Uses reflection to create a new SoftLimitMRUCache with a specified size and sets session factory query plan chache to it.
100+ /// This is done like this as NHibernate does not currently provide any way to specify the query plan cache size through configuration.
101+ /// </summary>
102+ /// <param name="factory"></param>
103+ /// <param name="size"></param>
104+ /// <returns></returns>
105+ private static bool TrySetQueryPlanCacheSize ( NHibernate . ISessionFactory factory , int size )
106+ {
107+ var factoryImpl = factory as NHibernate . Impl . SessionFactoryImpl ;
108+ if ( factoryImpl != null )
109+ {
110+ var queryPlanCacheFieldInfo = typeof ( NHibernate . Impl . SessionFactoryImpl ) . GetField ( "queryPlanCache" , System . Reflection . BindingFlags . Instance | System . Reflection . BindingFlags . NonPublic ) ;
111+ if ( queryPlanCacheFieldInfo != null )
112+ {
113+ var queryPlanCache = ( NHibernate . Engine . Query . QueryPlanCache ) queryPlanCacheFieldInfo . GetValue ( factoryImpl ) ;
114+
115+ var planCacheFieldInfo = typeof ( NHibernate . Engine . Query . QueryPlanCache ) . GetField ( "planCache" , System . Reflection . BindingFlags . Instance | System . Reflection . BindingFlags . NonPublic ) ;
116+ if ( planCacheFieldInfo != null )
117+ {
118+ var softLimitMRUCache = new NHibernate . Util . SoftLimitMRUCache ( size ) ;
119+
120+ planCacheFieldInfo . SetValue ( queryPlanCache , softLimitMRUCache ) ;
121+ return true ;
122+ }
123+ }
124+ }
125+ return false ;
126+ }
127+ }
128+ }
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