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1
21 package com.db4o.inside.freespace;
22
23 import com.db4o.*;
24 import com.db4o.foundation.*;
25 import com.db4o.inside.ix.*;
26
27
28 public class FreespaceManagerIx extends FreespaceManager{
29
30 private int _slotAddress;
31
32 private FreespaceIxAddress _addressIx;
33 private FreespaceIxLength _lengthIx;
34
35 private boolean _started;
36
37 private Collection4 _xBytes;
38
39 FreespaceManagerIx(YapFile file){
40 super(file);
41 }
42
43 private void add(int address, int length){
44 _addressIx.add(address, length);
45 _lengthIx.add(address, length);
46 }
47
48 public void beginCommit() {
49 if(! started()){
50 return;
51 }
52 slotEntryToZeroes(_file, _slotAddress);
53 }
54
55 public void debug(){
56 if(Debug.freespace){
57 System.out.println("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX");
58 System.out.println("Dumping file based address index");
59 _addressIx.debug();
60 System.out.println("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX");
61 System.out.println("Dumping file based length index");
62 _lengthIx.debug();
63 System.out.println("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX");
64 }
65 }
66
67 public void endCommit() {
68 if( ! started()){
69 return;
70 }
71 if (Debug.xbytes) {
72 _xBytes = new Collection4();
73 }
74
75 _addressIx._index.commitFreeSpace(_lengthIx._index);
76
77 YapWriter writer = new YapWriter(_file.getSystemTransaction(), _slotAddress, slotLength());
78 _addressIx._index._metaIndex.write(writer);
79 _lengthIx._index._metaIndex.write(writer);
80 if (Debug.xbytes) {
81 writer.setID(YapConst.IGNORE_ID); }
83 if(_file.configImpl().flushFileBuffers()){
84 _file.syncFiles();
85 }
86 writer.writeEncrypt();
87
88 if(Debug.xbytes){
89 Iterator4 i = _xBytes.iterator();
90 _xBytes = null;
91 while(i.moveNext()){
92 int[] addressLength = (int[])i.current();
93 writeXBytes(addressLength[0], addressLength[1]);
94 }
95 }
96 }
97
98 public int entryCount() {
99 return _addressIx.entryCount();
100 }
101
102 public void free(int address, int length) {
103
104 if(! started()){
105 return;
106 }
107
108 if (address <= 0) {
109 return;
110 }
111
112 if (length <= discardLimit()) {
113 return;
114 }
115
116 if(DTrace.enabled){
117 DTrace.FREE.logLength(address, length);
118 }
119
120 length = _file.blocksFor(length);
121
122 int freedAddress = address;
123 int freedLength = length;
124
125 _addressIx.find(address);
126
127 if(_addressIx.preceding()){
128 if(_addressIx.address() + _addressIx.length() == address){
129 remove(_addressIx.address(), _addressIx.length());
130 address = _addressIx.address();
131 length += _addressIx.length();
132 _addressIx.find(freedAddress);
133 }
134 }
135
136 if(_addressIx.subsequent()){
137 if(freedAddress + freedLength == _addressIx.address()){
138 remove(_addressIx.address(), _addressIx.length());
139 length += _addressIx.length();
140 }
141 }
142
143 add(address, length);
144
145 if (Debug.xbytes) {
146 writeXBytes(freedAddress, freedLength);
147 }
148 }
149
150 public void freeSelf() {
151 if(! started()){
152 return;
153 }
154 _addressIx._index._metaIndex.free(_file);
155 _lengthIx._index._metaIndex.free(_file);
156 }
157
158 public int freeSize() {
159 return _addressIx.freeSize();
160 }
161
162 public int getSlot(int length) {
163 if(! started()){
164 return 0;
165 }
166 int address = getSlot1(length);
167
168 if(address != 0){
169 if(DTrace.enabled){
170 DTrace.GET_FREESPACE.logLength(address, length);
171 }
172 }
173 return address;
174 }
175
176 private int getSlot1(int length) {
177
178 if(! started()){
179 return 0;
180 }
181
182 length = _file.blocksFor(length);
183
184 _lengthIx.find(length);
185
186 if(_lengthIx.match()){
187 remove(_lengthIx.address(), _lengthIx.length());
188 return _lengthIx.address();
189 }
190
191 if(_lengthIx.subsequent()){
192
193 int lengthRemainder = _lengthIx.length() - length;
194 int addressRemainder = _lengthIx.address() + length;
195 remove(_lengthIx.address(), _lengthIx.length());
196 add(addressRemainder, lengthRemainder);
197 return _lengthIx.address();
198 }
199
200 return 0;
201 }
202
203 public void migrate(final FreespaceManager newFM) {
204 if(! started()){
205 return;
206 }
207 final IntObjectVisitor addToNewFM = new IntObjectVisitor(){
208 public void visit(int length, Object  address) {
209 newFM.free(((Integer )address).intValue(), length);
210 }
211 };
212 Tree.traverse(_addressIx._indexTrans.getRoot(), new Visitor4() {
213 public void visit(Object a_object) {
214 IxTree ixTree = (IxTree)a_object;
215 ixTree.visitAll(addToNewFM);
216 }
217 });
218 }
219
220 public void onNew(YapFile file) {
221 file.ensureFreespaceSlot();
222 }
223
224 public void read(int freespaceID) {
225 }
227
228 private void remove(int address, int length){
229 _addressIx.remove(address, length);
230 _lengthIx.remove(address, length);
231 }
232
233 public void start(int slotAddress) {
234
235 if(started()){
236 return;
237 }
238
239 _slotAddress = slotAddress;
240
241 MetaIndex miAddress = new MetaIndex();
242 MetaIndex miLength = new MetaIndex();
243
244 YapReader reader = new YapReader(slotLength());
245 reader.read(_file, slotAddress, 0);
246 miAddress.read(reader);
247 miLength.read(reader);
248
249 _addressIx = new FreespaceIxAddress(_file, miAddress);
250 _lengthIx = new FreespaceIxLength(_file, miLength);
251
252 _started = true;
253 }
254
255
256 private boolean started(){
257 return _started;
258 }
259
260 public byte systemType() {
261 return FM_IX;
262 }
263
264 public int write(boolean shuttingDown) {
265 return 0; }
267
268 private void writeXBytes(int address, int length){
269 if (Debug.xbytes) {
270 if(_xBytes == null){
271 length = length * blockSize();
272 _file.debugWriteXBytes(address, length);
273 }else{
274 _xBytes.add(new int[] {address, length});
275 }
276 }
277 }
278
279 }
280 |
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