src/share/classes/java/util/zip/GZIPOutputStream.java

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 162                     // last deflater buffer. Fit trailer at the end
 163                     writeTrailer(buf, len);
 164                     len = len + TRAILER_SIZE;
 165                     out.write(buf, 0, len);
 166                     return;
 167                 }
 168                 if (len > 0)
 169                     out.write(buf, 0, len);
 170             }
 171             // if we can't fit the trailer at the end of the last
 172             // deflater buffer, we write it separately
 173             byte[] trailer = new byte[TRAILER_SIZE];
 174             writeTrailer(trailer, 0);
 175             out.write(trailer);
 176         }
 177     }
 178 
 179     /*
 180      * Writes GZIP member header.
 181      */
 182 
 183     private final static byte[] header = {
 184         (byte) GZIP_MAGIC,                // Magic number (short)
 185         (byte)(GZIP_MAGIC >> 8),          // Magic number (short)
 186         Deflater.DEFLATED,                // Compression method (CM)
 187         0,                                // Flags (FLG)
 188         0,                                // Modification time MTIME (int)
 189         0,                                // Modification time MTIME (int)
 190         0,                                // Modification time MTIME (int)
 191         0,                                // Modification time MTIME (int)
 192         0,                                // Extra flags (XFLG)
 193         0                                 // Operating system (OS)
 194     };
 195 
 196     private void writeHeader() throws IOException {
 197         out.write(header);
 198     }
 199 
 200     /*
 201      * Writes GZIP member trailer to a byte array, starting at a given
 202      * offset.
 203      */
 204     private void writeTrailer(byte[] buf, int offset) throws IOException {
 205         writeInt((int)crc.getValue(), buf, offset); // CRC-32 of uncompr. data
 206         writeInt(def.getTotalIn(), buf, offset + 4); // Number of uncompr. bytes
 207     }
 208 
 209     /*
 210      * Writes integer in Intel byte order to a byte array, starting at a
 211      * given offset.
 212      */
 213     private void writeInt(int i, byte[] buf, int offset) throws IOException {
 214         writeShort(i & 0xffff, buf, offset);
 215         writeShort((i >> 16) & 0xffff, buf, offset + 2);
 216     }
 217 


 162                     // last deflater buffer. Fit trailer at the end
 163                     writeTrailer(buf, len);
 164                     len = len + TRAILER_SIZE;
 165                     out.write(buf, 0, len);
 166                     return;
 167                 }
 168                 if (len > 0)
 169                     out.write(buf, 0, len);
 170             }
 171             // if we can't fit the trailer at the end of the last
 172             // deflater buffer, we write it separately
 173             byte[] trailer = new byte[TRAILER_SIZE];
 174             writeTrailer(trailer, 0);
 175             out.write(trailer);
 176         }
 177     }
 178 
 179     /*
 180      * Writes GZIP member header.
 181      */
 182     private void writeHeader() throws IOException {
 183         out.write(new byte[] {
 184                       (byte) GZIP_MAGIC,        // Magic number (short)
 185                       (byte)(GZIP_MAGIC >> 8),  // Magic number (short)
 186                       Deflater.DEFLATED,        // Compression method (CM)
 187                       0,                        // Flags (FLG)
 188                       0,                        // Modification time MTIME (int)
 189                       0,                        // Modification time MTIME (int)
 190                       0,                        // Modification time MTIME (int)
 191                       0,                        // Modification time MTIME (int)
 192                       0,                        // Extra flags (XFLG)
 193                       0                         // Operating system (OS)
 194                   });



 195     }
 196 
 197     /*
 198      * Writes GZIP member trailer to a byte array, starting at a given
 199      * offset.
 200      */
 201     private void writeTrailer(byte[] buf, int offset) throws IOException {
 202         writeInt((int)crc.getValue(), buf, offset); // CRC-32 of uncompr. data
 203         writeInt(def.getTotalIn(), buf, offset + 4); // Number of uncompr. bytes
 204     }
 205 
 206     /*
 207      * Writes integer in Intel byte order to a byte array, starting at a
 208      * given offset.
 209      */
 210     private void writeInt(int i, byte[] buf, int offset) throws IOException {
 211         writeShort(i & 0xffff, buf, offset);
 212         writeShort((i >> 16) & 0xffff, buf, offset + 2);
 213     }
 214