1 : /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2 : /* ***** BEGIN LICENSE BLOCK *****
3 : * Version: MPL 1.1/GPL 2.0/LGPL 2.1
4 : *
5 : * The contents of this file are subject to the Mozilla Public License Version
6 : * 1.1 (the "License"); you may not use this file except in compliance with
7 : * the License. You may obtain a copy of the License at
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11 : * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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13 : * License.
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15 : * The Original Code is mozilla.org code.
16 : *
17 : * The Initial Developer of the Original Code is Neil Deakin
18 : * Portions created by the Initial Developer are Copyright (C) 2005
19 : * the Initial Developer. All Rights Reserved.
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21 : * Contributor(s):
22 : *
23 : * Alternatively, the contents of this file may be used under the terms of
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36 :
37 : #ifndef nsRDFQuery_h__
38 : #define nsRDFQuery_h__
39 :
40 : #include "nsAutoPtr.h"
41 : #include "nsISimpleEnumerator.h"
42 : #include "nsCycleCollectionParticipant.h"
43 :
44 : #define NS_ITEMPLATERDFQUERY_IID \
45 : {0x8929ff60, 0x1c9c, 0x4d87, \
46 : { 0xac, 0x02, 0x09, 0x14, 0x15, 0x3b, 0x48, 0xc4 }}
47 :
48 : /**
49 : * A compiled query in the RDF query processor. This interface should not be
50 : * used directly outside of the RDF query processor.
51 : */
52 : class nsITemplateRDFQuery : public nsISupports
53 0 : {
54 : public:
55 : NS_DECLARE_STATIC_IID_ACCESSOR(NS_ITEMPLATERDFQUERY_IID)
56 :
57 : // return the processor the query was created from
58 : virtual nsXULTemplateQueryProcessorRDF* Processor() = 0; // not addrefed
59 :
60 : // return the member variable for the query
61 : virtual nsIAtom* GetMemberVariable() = 0; // not addrefed
62 :
63 : // return the <query> node the query was compiled from
64 : virtual void GetQueryNode(nsIDOMNode** aQueryNode) = 0;
65 :
66 : // remove any results that are cached by the query
67 : virtual void ClearCachedResults() = 0;
68 : };
69 :
70 : class nsRDFQuery : public nsITemplateRDFQuery
71 : {
72 : public:
73 :
74 0 : nsRDFQuery(nsXULTemplateQueryProcessorRDF* aProcessor)
75 : : mProcessor(aProcessor),
76 : mSimple(false),
77 : mRoot(nsnull),
78 0 : mCachedResults(nsnull)
79 0 : { }
80 :
81 0 : ~nsRDFQuery() { Finish(); }
82 :
83 0 : NS_DECL_CYCLE_COLLECTING_ISUPPORTS
84 1464 : NS_DECL_CYCLE_COLLECTION_CLASS(nsRDFQuery)
85 :
86 : /**
87 : * Retrieve the root node in the rule network
88 : * @return the root node in the rule network
89 : */
90 0 : TestNode* GetRoot() { return mRoot; }
91 :
92 0 : void SetRoot(TestNode* aRoot) { mRoot = aRoot; }
93 :
94 0 : void GetQueryNode(nsIDOMNode** aQueryNode)
95 : {
96 0 : *aQueryNode = mQueryNode;
97 0 : NS_IF_ADDREF(*aQueryNode);
98 0 : }
99 :
100 0 : void SetQueryNode(nsIDOMNode* aQueryNode)
101 : {
102 0 : mQueryNode = aQueryNode;
103 0 : }
104 :
105 : // an optimization is used when several queries all use the simple query
106 : // syntax. Since simple queries can only generate one possible set of
107 : // results, they only need to be calculated once and reused for every
108 : // simple query. The results may be cached in the query for this purpose.
109 : // If successful, this method takes ownership of aInstantiations.
110 : nsresult SetCachedResults(nsXULTemplateQueryProcessorRDF* aProcessor,
111 : const InstantiationSet& aInstantiations);
112 :
113 : // grab the cached results, if any, causing the caller to take ownership
114 : // of them. This also has the effect of setting the cached results in this
115 : // nsRDFQuery to null.
116 : void UseCachedResults(nsISimpleEnumerator** aResults);
117 :
118 : // clear the cached results
119 0 : void ClearCachedResults()
120 : {
121 0 : mCachedResults = nsnull;
122 0 : }
123 :
124 0 : nsXULTemplateQueryProcessorRDF* Processor() { return mProcessor; }
125 :
126 0 : nsIAtom* GetMemberVariable() { return mMemberVariable; }
127 :
128 0 : bool IsSimple() { return mSimple; }
129 :
130 0 : void SetSimple() { mSimple = true; }
131 :
132 : // the reference and member variables for the query
133 : nsCOMPtr<nsIAtom> mRefVariable;
134 : nsCOMPtr<nsIAtom> mMemberVariable;
135 :
136 : protected:
137 :
138 : nsXULTemplateQueryProcessorRDF* mProcessor;
139 :
140 : // true if the query is a simple rule (one with a default query)
141 : bool mSimple;
142 :
143 : /**
144 : * The root node in the network for this query
145 : */
146 : TestNode *mRoot;
147 :
148 : // the <query> node
149 : nsCOMPtr<nsIDOMNode> mQueryNode;
150 :
151 : // used for simple rules since their results are all determined in one step
152 : nsCOMPtr<nsISimpleEnumerator> mCachedResults;
153 :
154 : void Finish();
155 : };
156 :
157 : NS_DEFINE_STATIC_IID_ACCESSOR(nsRDFQuery, NS_ITEMPLATERDFQUERY_IID)
158 :
159 : #endif // nsRDFQuery_h__
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