// return true if got another repeat out of this record
// side effect is that the new record is in repeatRecord
private boolean nextRepeating() throws IOException {
raf.seek(repeatPos);
// octets 1-4 (Length of GDS)
int length = GribNumbers.int4(raf);
int section = raf.read();
raf.seek(repeatPos);
if (section == 2) {
repeatRecord.setLus(new Grib2SectionLocalUse(raf));
repeatRecord.setGdss(new Grib2SectionGridDefinition(raf));
repeatRecord.setPdss(new Grib2SectionProductDefinition(raf));
repeatRecord.setDrs(new Grib2SectionDataRepresentation(raf));
repeatRecord.setBms(new Grib2SectionBitMap(raf), false);
repeatRecord.setDataSection(new Grib2SectionData(raf));
repeatRecord.repeat = section;
} else if (section == 3) {
repeatRecord.setGdss(new Grib2SectionGridDefinition(raf));
repeatRecord.setPdss(new Grib2SectionProductDefinition(raf));
repeatRecord.setDrs(new Grib2SectionDataRepresentation(raf));
repeatRecord.setBms(new Grib2SectionBitMap(raf), false);
repeatRecord.setDataSection(new Grib2SectionData(raf));
repeatRecord.repeat = section;
} else if (section == 4) {
repeatRecord.setPdss(new Grib2SectionProductDefinition(raf));
repeatRecord.setDrs(new Grib2SectionDataRepresentation(raf));
repeatRecord.setBms(new Grib2SectionBitMap(raf), false);
repeatRecord.setDataSection(new Grib2SectionData(raf));
repeatRecord.repeat = section;
} else {
if (debugRepeat) System.out.printf(" REPEAT Terminate %d%n", section);
repeatPos = -1;
repeatRecord = null;
repeatBms = null;
return false;
}
// look for repeating bms
Grib2SectionBitMap bms = repeatRecord.getBitmapSection();
if (bms.getBitMapIndicator() == 254) {
// replace BMS with last good one
if (repeatBms == null) throw new IllegalStateException("No bms in repeating section");
repeatRecord.setBms(repeatBms, true);
// debug
if (debugRepeat) System.out.printf("replaced bms %d%n", section);
repeatRecord.repeat += 1000;
} else if (bms.getBitMapIndicator() == 0) {
// track last good bms
repeatBms = repeatRecord.getBitmapSection();
}
// keep only unique gds
if ((section == 2) || (section == 3)) {
// look for duplicate gds
Grib2SectionGridDefinition gds = repeatRecord.getGDSsection();
long crc = gds.calcCRC();
Grib2SectionGridDefinition gdsCached = gdsMap.get(crc);
if (gdsCached != null) repeatRecord.setGdss(gdsCached);
else gdsMap.put(crc, gds);
}
// check to see if we are at the end
long pos = raf.getFilePointer();
long ending = repeatRecord.getIs().getEndPos();
if (pos + 34 < ending) { // give it 30 bytes of slop
if (debugRepeat) System.out.printf(" REPEAT AGAIN %d != %d%n", pos + 4, ending);
repeatPos = pos;
return true;
}
if (debug)
System.out.printf(
" REPEAT read until %d grib ending at %d header ='%s'%n",
raf.getFilePointer(), ending, StringUtil2.cleanup(header));
// check that end section is correct
raf.seek(ending - 4);
for (int i = 0; i < 4; i++) {
if (raf.read() != 55) {
log.warn(
" REPEAT Missing End of GRIB message at pos="
+ ending
+ " header= "
+ StringUtil2.cleanup(header)
+ " for="
+ raf.getLocation());
break;
}
}
lastPos = raf.getFilePointer();
if (debugRepeat) System.out.printf(" REPEAT DONE%n");
repeatPos = -1; // no more repeats in this record
return true;
}
public Grib2Record next() throws IOException {
if (repeatRecord != null) { // serve current repeatRecord if it exists
return new Grib2Record(repeatRecord);
}
Grib2SectionIndicator is = null;
try {
is = new Grib2SectionIndicator(raf);
Grib2SectionIdentification ids = new Grib2SectionIdentification(raf);
Grib2SectionLocalUse lus = new Grib2SectionLocalUse(raf);
Grib2SectionGridDefinition gds = new Grib2SectionGridDefinition(raf);
Grib2SectionProductDefinition pds = new Grib2SectionProductDefinition(raf);
Grib2SectionDataRepresentation drs = new Grib2SectionDataRepresentation(raf);
Grib2SectionBitMap bms = new Grib2SectionBitMap(raf);
Grib2SectionData dataSection = new Grib2SectionData(raf);
if (dataSection.getMsgLength() > is.getMessageLength()) { // presumably corrupt
raf.seek(drs.getStartingPosition()); // go back to before the dataSection
throw new IllegalStateException("Illegal Grib2SectionData Message Length");
}
// look for duplicate gds
long crc = gds.calcCRC();
Grib2SectionGridDefinition gdsCached = gdsMap.get(crc);
if (gdsCached != null) gds = gdsCached;
else gdsMap.put(crc, gds);
// look for duplicate pds
/* crc = pds.calcCRC();
Grib2SectionProductDefinition pdsCached = pdsMap.get(crc);
if (pdsCached != null)
pds = pdsCached;
else
pdsMap.put(crc, pds); */
// check to see if we have a repeating record
long pos = raf.getFilePointer();
long ending = is.getEndPos();
if (pos + 34 < ending) { // give it 30 bytes of slop
if (debugRepeat) System.out.printf(" REPEAT AT %d != %d%n", pos + 4, ending);
repeatPos = pos;
repeatRecord =
new Grib2Record(
header,
is,
ids,
lus,
gds,
pds,
drs,
bms,
dataSection,
false); // this assumes immutable sections
// track bms in case its a repeat
if (bms.getBitMapIndicator() == 0) repeatBms = bms;
return new Grib2Record(
repeatRecord); // GribRecord isnt immutable; still may not be necessary
}
if (debug)
System.out.printf(
" read until %d grib ending at %d header ='%s'%n",
raf.getFilePointer(), ending, StringUtil2.cleanup(header));
// check that end section is correct
raf.seek(ending - 4);
for (int i = 0; i < 4; i++) {
if (raf.read() != 55) {
log.warn(
"Missing End of GRIB message at pos="
+ ending
+ " header= "
+ StringUtil2.cleanup(header)
+ " for="
+ raf.getLocation());
break;
}
}
lastPos = raf.getFilePointer();
return new Grib2Record(header, is, ids, lus, gds, pds, drs, bms, dataSection, false);
} catch (Throwable t) {
long pos = (is == null) ? -1 : is.getStartPos();
log.warn("Bad GRIB2 record in file {}, skipping pos={}", raf.getLocation(), pos);
lastPos = raf.getFilePointer();
if (hasNext()) // skip forward
return next();
}
return null; // last record was incomplete
}
