| 1 | /* |
| 2 | |
| 3 | Derby - Class org.apache.derby.impl.services.uuid.BasicUUID |
| 4 | |
| 5 | Copyright 1997, 2004 The Apache Software Foundation or its licensors, as applicable. |
| 6 | |
| 7 | Licensed under the Apache License, Version 2.0 (the "License"); |
| 8 | you may not use this file except in compliance with the License. |
| 9 | You may obtain a copy of the License at |
| 10 | |
| 11 | http://www.apache.org/licenses/LICENSE-2.0 |
| 12 | |
| 13 | Unless required by applicable law or agreed to in writing, software |
| 14 | distributed under the License is distributed on an "AS IS" BASIS, |
| 15 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 16 | See the License for the specific language governing permissions and |
| 17 | limitations under the License. |
| 18 | |
| 19 | */ |
| 20 | |
| 21 | package org.apache.derby.impl.services.uuid; |
| 22 | |
| 23 | import org.apache.derby.iapi.services.io.FormatIdUtil; |
| 24 | import org.apache.derby.iapi.services.io.StoredFormatIds; |
| 25 | import org.apache.derby.iapi.services.io.Formatable; |
| 26 | |
| 27 | import org.apache.derby.catalog.UUID; |
| 28 | |
| 29 | import java.io.ObjectOutput; |
| 30 | import java.io.ObjectInput; |
| 31 | import java.io.IOException; |
| 32 | |
| 33 | import java.io.StringReader; |
| 34 | |
| 35 | |
| 36 | public class BasicUUID implements UUID, Formatable |
| 37 | { |
| 38 | /* |
| 39 | ** Fields of BasicUUID |
| 40 | */ |
| 41 | |
| 42 | private long majorId; // only using 48 bits |
| 43 | private long timemillis; |
| 44 | private int sequence; |
| 45 | |
| 46 | /* |
| 47 | ** Methods of BasicUUID |
| 48 | */ |
| 49 | |
| 50 | /** |
| 51 | Constructor only called by BasicUUIDFactory. |
| 52 | **/ |
| 53 | public BasicUUID(long majorId, long timemillis, int sequence) |
| 54 | { |
| 55 | this.majorId = majorId; |
| 56 | this.timemillis = timemillis; |
| 57 | this.sequence = sequence; |
| 58 | } |
| 59 | |
| 60 | /** |
| 61 | Constructor only called by BasicUUIDFactory. |
| 62 | Constructs a UUID from the string representation |
| 63 | produced by toString. |
| 64 | @see BasicUUID#toString |
| 65 | **/ |
| 66 | public BasicUUID(String uuidstring) |
| 67 | { |
| 68 | StringReader sr = new StringReader(uuidstring); |
| 69 | sequence = (int) readMSB(sr); |
| 70 | |
| 71 | long ltimemillis = readMSB(sr) << 32; |
| 72 | ltimemillis += readMSB(sr) << 16; |
| 73 | ltimemillis += readMSB(sr); |
| 74 | timemillis = ltimemillis; |
| 75 | majorId = readMSB(sr); |
| 76 | } |
| 77 | |
| 78 | /** |
| 79 | Constructor only called by BasicUUIDFactory. |
| 80 | Constructs a UUID from the byte array representation |
| 81 | produced by toByteArrayio. |
| 82 | @see BasicUUID#toByteArray |
| 83 | **/ |
| 84 | public BasicUUID(byte[] b) |
| 85 | { |
| 86 | int lsequence = 0; |
| 87 | for (int ix = 0; ix < 4; ix++) |
| 88 | { |
| 89 | lsequence = lsequence << 8; |
| 90 | lsequence = lsequence | (0xff & b[ix]); |
| 91 | } |
| 92 | |
| 93 | long ltimemillis = 0; |
| 94 | for (int ix = 4; ix < 10; ix++) |
| 95 | { |
| 96 | ltimemillis = ltimemillis << 8; |
| 97 | ltimemillis = ltimemillis | (0xff & b[ix]); |
| 98 | } |
| 99 | |
| 100 | long linetaddr = 0; |
| 101 | for (int ix = 10; ix < 16; ix++) |
| 102 | { |
| 103 | linetaddr = linetaddr << 8; |
| 104 | linetaddr = linetaddr | (0xff & b[ix]); |
| 105 | } |
| 106 | |
| 107 | sequence = lsequence; |
| 108 | timemillis = ltimemillis; |
| 109 | majorId = linetaddr; |
| 110 | } |
| 111 | |
| 112 | /* |
| 113 | * Formatable methods |
| 114 | */ |
| 115 | |
| 116 | // no-arg constructor, required by Formatable |
| 117 | public BasicUUID() { super(); } |
| 118 | |
| 119 | /** |
| 120 | Write this out. |
| 121 | @exception IOException error writing to log stream |
| 122 | */ |
| 123 | public void writeExternal(ObjectOutput out) throws IOException |
| 124 | { |
| 125 | // RESOLVE: write out the byte array instead? |
| 126 | out.writeLong(majorId); |
| 127 | out.writeLong(timemillis); |
| 128 | out.writeInt(sequence); |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | Read this in |
| 133 | @exception IOException error reading from log stream |
| 134 | */ |
| 135 | public void readExternal(ObjectInput in) throws IOException |
| 136 | { |
| 137 | majorId = in.readLong(); |
| 138 | timemillis = in.readLong(); |
| 139 | sequence = in.readInt(); |
| 140 | } |
| 141 | |
| 142 | /** |
| 143 | Return my format identifier. |
| 144 | */ |
| 145 | public int getTypeFormatId() { |
| 146 | return StoredFormatIds.BASIC_UUID; |
| 147 | } |
| 148 | |
| 149 | private static void writeMSB(char[] data, int offset, long value, int nbytes) |
| 150 | { |
| 151 | for (int i = nbytes - 1; i >= 0; i--) |
| 152 | { |
| 153 | long b = (value & (255L << (8 * i))) >>> (8 * i); |
| 154 | |
| 155 | int c = (int) ((b & 0xf0) >> 4); |
| 156 | data[offset++] = (char) (c < 10 ? c + '0' : (c - 10) + 'a'); |
| 157 | c = (int) (b & 0x0f); |
| 158 | data[offset++] = (char) (c < 10 ? c + '0' : (c - 10) + 'a'); |
| 159 | } |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | Read a long value, msb first, from its character |
| 164 | representation in the string reader, using '-' or |
| 165 | end of string to delimit. |
| 166 | **/ |
| 167 | private static long readMSB(StringReader sr) |
| 168 | { |
| 169 | long value = 0; |
| 170 | |
| 171 | try |
| 172 | { |
| 173 | int c; |
| 174 | while ((c = sr.read()) != -1) |
| 175 | { |
| 176 | if (c == '-') |
| 177 | break; |
| 178 | value <<= 4; |
| 179 | |
| 180 | int nibble; |
| 181 | if (c <= '9') |
| 182 | nibble = c - '0'; |
| 183 | else if (c <= 'F') |
| 184 | nibble = c - 'A' + 10; |
| 185 | else |
| 186 | nibble = c - 'a' + 10; |
| 187 | value += nibble; |
| 188 | } |
| 189 | } |
| 190 | catch (Exception e) |
| 191 | { |
| 192 | } |
| 193 | |
| 194 | return value; |
| 195 | } |
| 196 | |
| 197 | /* |
| 198 | ** Methods of UUID |
| 199 | */ |
| 200 | |
| 201 | /** |
| 202 | Implement value equality. |
| 203 | |
| 204 | **/ |
| 205 | public boolean equals(Object otherObject) |
| 206 | { |
| 207 | if (!(otherObject instanceof BasicUUID)) |
| 208 | return false; |
| 209 | |
| 210 | BasicUUID other = (BasicUUID) otherObject; |
| 211 | |
| 212 | return (this.sequence == other.sequence) |
| 213 | && (this.timemillis == other.timemillis) |
| 214 | && (this.majorId == other.majorId); |
| 215 | } |
| 216 | |
| 217 | /** |
| 218 | Provide a hashCode which is compatible with |
| 219 | the equals() method. |
| 220 | **/ |
| 221 | public int hashCode() |
| 222 | { |
| 223 | long hc = majorId ^ timemillis; |
| 224 | |
| 225 | return sequence ^ ((int) (hc >> 4)); |
| 226 | } |
| 227 | |
| 228 | /** |
| 229 | Produce a string representation of this UUID which |
| 230 | can be passed to UUIDFactory.recreateUUID later on |
| 231 | to reconstruct it. The funny representation is |
| 232 | designed to (sort of) match the format of Microsoft's |
| 233 | UUIDGEN utility. |
| 234 | */ |
| 235 | public String toString() {return stringWorkhorse( '-' );} |
| 236 | |
| 237 | /** |
| 238 | Produce a string representation of this UUID which |
| 239 | is suitable for use as a unique ANSI identifier. |
| 240 | */ |
| 241 | public String toANSIidentifier() {return "U" + stringWorkhorse( 'X' );} |
| 242 | |
| 243 | /** |
| 244 | * Private workhorse of the string making routines. |
| 245 | * |
| 246 | * @param separator Character to separate number blocks. |
| 247 | * Null means do not include a separator. |
| 248 | * |
| 249 | * @return string representation of UUID. |
| 250 | */ |
| 251 | public String stringWorkhorse( char separator ) |
| 252 | { |
| 253 | char[] data = new char[36]; |
| 254 | |
| 255 | writeMSB(data, 0, (long) sequence, 4); |
| 256 | |
| 257 | int offset = 8; |
| 258 | if (separator != 0) data[offset++] = separator; |
| 259 | |
| 260 | long ltimemillis = timemillis; |
| 261 | writeMSB(data, offset, (ltimemillis & 0x0000ffff00000000L) >>> 32, 2); |
| 262 | offset += 4; |
| 263 | if (separator != 0) data[offset++] = separator; |
| 264 | writeMSB(data, offset, (ltimemillis & 0x00000000ffff0000L) >>> 16, 2); |
| 265 | offset += 4; |
| 266 | if (separator != 0) data[offset++] = separator; |
| 267 | writeMSB(data, offset, (ltimemillis & 0x000000000000ffffL), 2); |
| 268 | offset += 4; |
| 269 | if (separator != 0) data[offset++] = separator; |
| 270 | writeMSB(data, offset, majorId, 6); |
| 271 | offset += 12; |
| 272 | |
| 273 | return new String(data, 0, offset); |
| 274 | } |
| 275 | |
| 276 | /** |
| 277 | Store this UUID in a byte array. Arrange the bytes in the UUID |
| 278 | in the same order the code which stores a UUID in a string |
| 279 | does. |
| 280 | |
| 281 | @see org.apache.derby.catalog.UUID#toByteArray |
| 282 | */ |
| 283 | public byte[] toByteArray() |
| 284 | { |
| 285 | byte[] result = new byte[16]; |
| 286 | |
| 287 | int lsequence = sequence; |
| 288 | result[0] = (byte)(lsequence >>> 24); |
| 289 | result[1] = (byte)(lsequence >>> 16); |
| 290 | result[2] = (byte)(lsequence >>> 8); |
| 291 | result[3] = (byte)lsequence; |
| 292 | |
| 293 | long ltimemillis = timemillis; |
| 294 | result[4] = (byte)(ltimemillis >>> 40); |
| 295 | result[5] = (byte)(ltimemillis >>> 32); |
| 296 | result[6] = (byte)(ltimemillis >>> 24); |
| 297 | result[7] = (byte)(ltimemillis >>> 16); |
| 298 | result[8] = (byte)(ltimemillis >>> 8); |
| 299 | result[9] = (byte)ltimemillis; |
| 300 | |
| 301 | long linetaddr = majorId; |
| 302 | result[10] = (byte)(linetaddr >>> 40); |
| 303 | result[11] = (byte)(linetaddr >>> 32); |
| 304 | result[12] = (byte)(linetaddr >>> 24); |
| 305 | result[13] = (byte)(linetaddr >>> 16); |
| 306 | result[14] = (byte)(linetaddr >>> 8); |
| 307 | result[15] = (byte)linetaddr; |
| 308 | |
| 309 | return result; |
| 310 | } |
| 311 | |
| 312 | /** |
| 313 | Clone this UUID. |
| 314 | |
| 315 | @return a copy of this UUID |
| 316 | */ |
| 317 | public UUID cloneMe() |
| 318 | { |
| 319 | return new BasicUUID(majorId, timemillis, sequence); |
| 320 | } |
| 321 | |
| 322 | public String toHexString() {return stringWorkhorse( (char) 0 );} |
| 323 | } |
| 324 | |