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1
30
31
32 package org.hsqldb.persist;
33
34 import java.io.IOException  ;
35
36 import org.hsqldb.Database;
37
38
51 public class ScaledRAFileHybrid implements ScaledRAInterface {
52
53 final Database database;
54 final String fileName;
55 final boolean isReadOnly;
56 final boolean wasNio;
57 long maxLength;
58 ScaledRAInterface store;
59
60 public ScaledRAFileHybrid(Database database, String name,
61 boolean readOnly) throws IOException {
62
63 this.database = database;
64 this.fileName = name;
65 this.isReadOnly = readOnly;
66
67 newStore(0);
68
69 this.wasNio = store.wasNio();
70 }
71
72 public long length() throws IOException {
73 return store.length();
74 }
75
76 public void seek(long position) throws IOException {
77 checkSeek(position);
78 store.seek(position);
79 }
80
81 public long getFilePointer() throws IOException {
82 return store.getFilePointer();
83 }
84
85 public int read() throws IOException {
86
87 checkLength(1);
88
89 return store.read();
90 }
91
92 public void read(byte[] b, int offset, int length) throws IOException {
93 checkLength(length);
94 store.read(b, offset, length);
95 }
96
97 public void write(byte[] b, int offset, int length) throws IOException {
98 checkLength(length);
99 store.write(b, offset, length);
100 }
101
102 public int readInt() throws IOException {
103
104 checkLength(4);
105
106 return store.readInt();
107 }
108
109 public void writeInt(int i) throws IOException {
110 checkLength(4);
111 store.writeInt(i);
112 }
113
114 public long readLong() throws IOException {
115
116 checkLength(8);
117
118 return store.readLong();
119 }
120
121 public void writeLong(long i) throws IOException {
122 checkLength(8);
123 store.writeLong(i);
124 }
125
126 public void close() throws IOException {
127 store.close();
128 }
129
130 public boolean isReadOnly() {
131 return store.isReadOnly();
132 }
133
134 public boolean wasNio() {
135 return wasNio;
136 }
137
138 public boolean canAccess(int length) {
139 return true;
140 }
141
142 public boolean canSeek(long position) {
143 return true;
144 }
145
146 public Database getDatabase() {
147 return null;
148 }
149
150 private void checkLength(int length) throws IOException {
151
152 if (store.canAccess(length)) {
153 return;
154 }
155
156 newStore(store.getFilePointer() + length);
157 }
158
159 private void checkSeek(long position) throws IOException {
160
161 if (store.canSeek(position)) {
162 return;
163 }
164
165 newStore(position);
166 }
167
168 void newStore(long requiredPosition) throws IOException {
169
170 long currentPosition = 0;
171
172 if (store != null) {
173 currentPosition = store.getFilePointer();
174
175 store.close();
176 }
177
178 if (requiredPosition <= ScaledRAFile.MAX_NIO_LENGTH) {
179 try {
180 store = new ScaledRAFileNIO(database, fileName, isReadOnly,
181 (int) requiredPosition);
182
183 store.seek(currentPosition);
184
185 return;
186 } catch (Throwable e) {}
187 }
188
189 store = new ScaledRAFile(database, fileName, isReadOnly);
190
191 store.seek(currentPosition);
192 }
193 }
194 |
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