private DataChunk readSamples(String channelName, Timestamp from) throws Exception {
DataChunk chunk = new DataChunk(chunkSize);
BufferedReader br = null;
String currentLine = "";
Timestamp lastIndex = indexes.floorKey(from);
Integer lineToStart = lastIndex == null ? 1 : indexes.get(lastIndex);
Integer lineNumber = -1;
try {
br = new BufferedReader(new FileReader(csvFile));
while ((currentLine = br.readLine()) != null) {
lineNumber++;
if (lineNumber < lineToStart) continue;
String[] columns = getColumns(currentLine);
if (columns[channel_name] != null && columns[channel_name].equals(channelName)) {
// Get time stamp
final java.sql.Timestamp stamp = java.sql.Timestamp.valueOf(columns[smpl_time]);
stamp.setNanos(Integer.valueOf(columns[nanosecs]));
final Timestamp time = fromSQLTimestamp(stamp);
if (time.compareTo(from) >= 0) {
final VType value = decodeValue(columns, time);
SourceData data = new SourceData(time, value);
if (!chunk.add(data)) {
TimeInterval i = chunk.getInterval();
if (i != null) indexes.put(i.getEnd(), lineNumber);
break;
}
}
}
}
} finally {
if (br != null) br.close();
}
return chunk;
}
/**
* Returns <code>true</code> if {@link TimeInterval} i1 intersects {@link TimeInterval} i2, <code>
* false</code> otherwise (<code>null</code> border means infinity).
*/
public static boolean intersects(TimeInterval i1, TimeInterval i2) {
if (i1 == null || i2 == null) return false;
i1 = arrange(i1);
i2 = arrange(i2);
if (i1.getStart() == null && i1.getEnd() == null) {
return true;
} else if (i1.getStart() != null && i1.getEnd() == null) {
if (i2.getEnd() == null) return true;
else if (i2.getStart() == null && i2.getEnd() != null) return i1.contains(i2.getEnd());
else return i1.contains(i2.getEnd()) || i1.contains(i2.getStart());
} else if (i1.getStart() == null && i1.getEnd() != null) {
if (i2.getStart() == null) return true;
else if (i2.getStart() != null && i2.getEnd() == null) return i1.contains(i2.getStart());
else return i1.contains(i2.getEnd()) || i1.contains(i2.getStart());
} else {
if (i2.getStart() == null && i2.getEnd() == null) return true;
else if (i2.getStart() == null || i2.getEnd() == null)
return i2.contains(i1.getEnd()) || i2.contains(i1.getStart());
else
return i1.contains(i2.getStart())
|| i1.contains(i2.getEnd())
|| i2.contains(i1.getStart())
|| i2.contains(i1.getEnd());
}
}
/**
* Returns <code>true</code> if {@link TimeInterval} i1 contains {@link TimeInterval} i2, <code>
* false</code> otherwise (<code>null</code> border means infinity).
*/
public static boolean contains(TimeInterval i1, TimeInterval i2) {
if (i1 == null || i2 == null) return false;
i1 = arrange(i1);
i2 = arrange(i2);
if (i2.getStart() == null && i2.getEnd() == null)
return i1.getStart() == null && i1.getEnd() == null;
else if (i2.getStart() != null && i2.getEnd() == null)
return i1.contains(i2.getStart()) && i1.getEnd() == null;
else if (i2.getStart() == null && i2.getEnd() != null)
return i1.getStart() == null && i1.contains(i2.getEnd());
else return i1.contains(i2.getStart()) && i1.contains(i2.getEnd());
}
/** Returns a formated {@link String} from the specified {@link TimeInterval}. */
public static String format(TimeInterval i) {
if (i == null) return "[]";
return "[" + format(i.getStart()) + " - " + format(i.getEnd()) + "]";
}
/** Returns a re-arranged {@link TimeInterval} if borders order is reversed. */
public static TimeInterval arrange(TimeInterval i) {
if (i.getStart() != null && i.getEnd() != null && i.getStart().compareTo(i.getEnd()) > 0)
return TimeInterval.between(i.getEnd(), i.getStart());
return i;
}
/**
* Returns the result of {@link TimeInterval} i1 & i2 intersection, <code>null</code> if i1
* does not intersects i2 (<code>null</code> border means infinity).
*/
public static TimeInterval intersection(TimeInterval i1, TimeInterval i2) {
if (i1 == null || i2 == null) return null;
if (!intersects(i1, i2)) return null;
i1 = arrange(i1);
i2 = arrange(i2);
Instant a = null;
if (i1.getStart() == null && i2.getStart() == null) a = null;
else if (i1.getStart() == null && i2.getStart() != null) a = i2.getStart();
else if (i1.getStart() != null && i2.getStart() == null) a = i1.getStart();
else a = max(i1.getStart(), i2.getStart());
Instant b = null;
if (i1.getEnd() == null && i2.getEnd() == null) b = null;
else if (i1.getEnd() == null && i2.getEnd() != null) b = i2.getEnd();
else if (i1.getEnd() != null && i2.getEnd() == null) b = i1.getEnd();
else b = min(i1.getEnd(), i2.getEnd());
return TimeInterval.between(a, b);
}