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1
21 package com.db4o;
22
23 import com.db4o.foundation.*;
24 import com.db4o.inside.marshall.*;
25 import com.db4o.inside.replication.*;
26 import com.db4o.inside.slots.*;
27
28
31 public abstract class YapFieldVirtual extends YapField {
32
33 YapFieldVirtual() {
34 super(null);
35 }
36
37 public abstract void addFieldIndex(MarshallerFamily mf, YapClass yapClass, YapWriter a_writer, Slot oldSlot);
38
39 public boolean alive() {
40 return true;
41 }
42
43 public void calculateLengths(Transaction trans, ObjectHeaderAttributes header, Object  obj){
44 header.addBaseLength(linkLength());
45 }
46
47 boolean canAddToQuery(String fieldName){
48 return fieldName.equals(getName());
49 }
50
51 public boolean canUseNullBitmap(){
52 return false;
53 }
54
55 void collectConstraints(Transaction a_trans, QConObject a_parent,
56 Object a_template, Visitor4 a_visitor) {
57
58
62 }
63
64 void deactivate(Transaction a_trans, Object a_onObject, int a_depth) {
65 }
67
68 public abstract void delete(MarshallerFamily mf, YapWriter a_bytes, boolean isUpdate);
69
70 public Object getOrCreate(Transaction a_trans, Object a_OnObject) {
71 return null;
74 }
75
76 public boolean needsArrayAndPrimitiveInfo(){
77 return false;
78 }
79
80 public boolean needsHandlerId(){
81 return false;
82 }
83
84 public void instantiate(MarshallerFamily mf, YapObject a_yapObject, Object a_onObject, YapWriter a_bytes)
85 throws CorruptionException {
86 a_yapObject.produceVirtualAttributes();
87 instantiate1(a_bytes.getTransaction(), a_yapObject, a_bytes);
88 }
89
90 abstract void instantiate1(Transaction a_trans, YapObject a_yapObject, YapReader a_bytes);
91
92 public void loadHandler(YapStream a_stream){
93 }
95
96 public final void marshall(
97 YapObject a_yapObject,
98 Object a_object,
99 MarshallerFamily mf,
100 YapWriter a_bytes,
101 Config4Class a_config,
102 boolean a_new) {
103
104 Transaction trans = a_bytes.i_trans;
105
106 if(! trans.supportsVirtualFields()){
107 marshallIgnore(a_bytes);
108 return;
109 }
110
111 YapStream stream = trans.stream();
112 YapHandlers handlers = stream.i_handlers;
113 boolean migrating = false;
114
115
116 if (stream._replicationCallState != YapConst.NONE) {
117 if (stream._replicationCallState == YapConst.OLD) {
118
119
121 migrating = true;
122 if (a_yapObject.virtualAttributes() == null) {
123 Object obj = a_yapObject.getObject();
124 YapObject migrateYapObject = null;
125 MigrationConnection mgc = handlers.i_migration;
126 if(mgc != null){
127 migrateYapObject = mgc.referenceFor(obj);
128 if(migrateYapObject == null){
129 migrateYapObject = mgc.peer(stream).getYapObject(obj);
130 }
131 }
132 if (migrateYapObject != null){
133 VirtualAttributes migrateAttributes = migrateYapObject.virtualAttributes();
134 if(migrateAttributes != null && migrateAttributes.i_database != null){
135 migrating = true;
136 a_yapObject.setVirtualAttributes((VirtualAttributes)migrateAttributes.shallowClone());
137 migrateAttributes.i_database.bind(trans);
138 }
139 }
140 }
141 }else {
142
143
145 Db4oReplicationReferenceProvider provider = handlers._replicationReferenceProvider;
146 Object parentObject = a_yapObject.getObject();
147 Db4oReplicationReference ref = provider.referenceFor(parentObject);
148 if(ref != null){
149 migrating = true;
150 VirtualAttributes va = a_yapObject.produceVirtualAttributes();
151 va.i_version = ref.version();
152 va.i_uuid = ref.longPart();
153 va.i_database = ref.signaturePart();
154 }
155 }
156 }
157
158 if (a_yapObject.virtualAttributes() == null) {
159 a_yapObject.produceVirtualAttributes();
160 migrating = false;
161 }
162 marshall1(a_yapObject, a_bytes, migrating, a_new);
163 }
164
165 abstract void marshall1(YapObject a_yapObject, YapWriter a_bytes,
166 boolean a_migrating, boolean a_new);
167
168 abstract void marshallIgnore(YapReader writer);
169
170 public void readVirtualAttribute(Transaction a_trans, YapReader a_reader, YapObject a_yapObject) {
171 if(! a_trans.supportsVirtualFields()){
172 a_reader.incrementOffset(linkLength());
173 return;
174 }
175 instantiate1(a_trans, a_yapObject, a_reader);
176 }
177
178 public boolean isVirtual() {
179 return true;
180 }
181
182 } |
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