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1
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12 package com.versant.core.jdo;
13
14 import java.lang.ref.Reference  ;
15 import java.lang.ref.ReferenceQueue ;
16
17 import com.versant.core.common.*;
18
19
24 public class PMCacheEntry {
25
26
29 private Object ref;
30
33 public PMCacheEntry processListNext;
34 public PMCacheEntry processListPrev;
35
36 public PMCacheEntry next;
37 public PMCacheEntry prev;
38
39 public int hash;
40
46 private int type;
47
50 public OID mappedOID;
51
52 public PMCacheEntry() {
53 }
54
55 public PMCacheEntry(int type, PCStateMan sm, ReferenceQueue queue) {
56 LocalPMCache.checkRefType(type);
57 this.type = type;
58 if (sm.oid.getRealOID() == null) {
59 this.hash = sm.oid.hashCode();
60 this.mappedOID = sm.oid;
61 } else {
62 this.mappedOID = sm.oid.getRealOID();
63 this.hash = sm.oid.getRealOID().hashCode();
64 }
65
66 switch (type) {
67 case VersantPersistenceManager.PM_CACHE_REF_TYPE_STRONG:
68 ref = sm;
69 break;
70 case VersantPersistenceManager.PM_CACHE_REF_TYPE_SOFT:
71 ref = new SoftCacheEntryRef(sm, queue, this);
72 break;
73 case VersantPersistenceManager.PM_CACHE_REF_TYPE_WEAK:
74 ref = new WeakCacheEntryRef(sm, queue, this);
75 break;
76 default:
77 throw BindingSupportImpl.getInstance().internal("Unknown option: " + type);
78 }
79 }
80
81 public PMCacheEntry(int type, OID oid, State state, ReferenceQueue queue) {
82 LocalPMCache.checkRefType(type);
83 this.type = type;
84 this.hash = oid.hashCode();
85 this.mappedOID = oid;
86 if (mappedOID == null) {
87 throw BindingSupportImpl.getInstance().internal("");
88 }
89 switch (type) {
90 case VersantPersistenceManager.PM_CACHE_REF_TYPE_STRONG:
91 ref = state;
92 break;
93 case VersantPersistenceManager.PM_CACHE_REF_TYPE_SOFT:
94 ref = new SoftCacheEntryRef(state, queue, this);
95 break;
96 case VersantPersistenceManager.PM_CACHE_REF_TYPE_WEAK:
97 ref = new WeakCacheEntryRef(state, queue, this);
98 break;
99 default:
100 throw BindingSupportImpl.getInstance().internal("Unknown option: " + type);
101 }
102 }
103
104 public void unlinkProcessList() {
105 if (processListNext != null) {
106 processListNext.processListPrev = null;
107 }
108 if (processListPrev != null) {
109 processListPrev.processListNext = null;
110 }
111
112 processListNext = null;
113 processListPrev = null;
114 }
115
116 public void unlinkNextList() {
117 if (prev != null) {
118 prev.next = next;
119 }
120 if (next != null) {
121 next.prev = prev;
122 }
123 next = null;
124 prev = null;
125 }
126
127
130 public PCStateMan upgradeToSm(PCStateMan sm, ReferenceQueue queue) {
131 sm.cacheEntry = this;
132 switch (type) {
133 case VersantPersistenceManager.PM_CACHE_REF_TYPE_STRONG:
134 ref = sm;
135 break;
136 case VersantPersistenceManager.PM_CACHE_REF_TYPE_SOFT:
137 ((Reference )ref).clear();
138 ref = new SoftCacheEntryRef(sm, queue, this);
139 break;
140 case VersantPersistenceManager.PM_CACHE_REF_TYPE_WEAK:
141 ((Reference )ref).clear();
142 ref = new WeakCacheEntryRef(sm, queue, this);
143 break;
144 default:
145 throw BindingSupportImpl.getInstance().internal("Unknown option: " + type);
146 }
147 return sm;
148 }
149
150 public void setNext(PMCacheEntry nextEntry) {
151 if (Debug.DEBUG) {
152 if (nextEntry == this) {
153 throw BindingSupportImpl.getInstance().internal("");
154 }
155 }
156 next = nextEntry;
157 if (next != null) {
158 next.prev = this;
159 }
160 }
161
162 public int hashCode() {
163 return hash;
164 }
165
166
169 public void reHash(OID newOID) {
170 mappedOID = newOID;
171 hash = newOID.hashCode();
172 }
173
174
178 public Object get() {
179 if (ref instanceof Reference ) {
180 return ((Reference )ref).get();
181 }
182 return ref;
183 }
184
185 public boolean hasReference(Object obj) {
186 return (obj == ref);
187 }
188
189 public void clear() {
190 if (ref instanceof Reference ) {
191 ((Reference )ref).clear();
192 }
193 ref = null;
194 }
195
196 public void reset() {
197 clear();
198 next = null;
199 prev = null;
200 processListNext = null;
201 processListPrev = null;
202 }
203
204 public String toString() {
205 return "CacheEntryBase@" + System.identityHashCode(this) + " oid " + (mappedOID == null ? "null" : mappedOID.toStringImp());
206 }
207
208 public void changeToRefType(ReferenceQueue queue, int newType) {
209 LocalPMCache.checkRefType(newType);
210
211 if (this.type == newType) return;
212 Object oldRef = get();
213 clear();
214
215 this.type = newType;
216 switch (newType) {
217 case VersantPersistenceManager.PM_CACHE_REF_TYPE_STRONG:
218 ref = oldRef;
219 break;
220 case VersantPersistenceManager.PM_CACHE_REF_TYPE_SOFT:
221 ref = new SoftCacheEntryRef(oldRef, queue, this);
222 break;
223 case VersantPersistenceManager.PM_CACHE_REF_TYPE_WEAK:
224 ref = new WeakCacheEntryRef(oldRef, queue, this);
225 break;
226 default:
227 throw BindingSupportImpl.getInstance().internal("Unknown option: " + type);
228 }
229 }
230 }
231 |
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