package com.bigdata.counters.render;
import java.io.IOException;
import java.io.Writer;
import java.util.regex.Pattern;
import com.bigdata.counters.ICounter;
import com.bigdata.counters.IHistoryEntry;
import com.bigdata.counters.query.HistoryTable;
import com.bigdata.counters.query.QueryUtil;
/**
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
public class TabDelimitedHistoryTableRenderer extends
HistoryTableRenderer {
/**
*
* @param tbl
* @param pattern
* Used to identify capturing groups and extract column
* labels.
* @param formatter
*/
public TabDelimitedHistoryTableRenderer(HistoryTable tbl,
Pattern pattern, ValueFormatter formatter) {
super(tbl, pattern, formatter);
}
/**
* Generate the table.
* <p>
* The table has one column for each counter having history data. The
* 1st header row of the table has the counter path. The seconds header
* row has just the counter name. The data rows are the samples from
* each period of the history for each counter.
*/
public void render(final Writer w) throws IOException {
// the header rows.
{
// header row.
w.write("From: " + formatter.date(t.firstTimestamp));
w.write("\tTo: " + formatter.date(t.lastTimestamp));
w.write("\n");
// header row.
w.write("\t");
for (ICounter counter : t.a) {
formatter.writeFullPath(w, counter.getPath());
w.write("\t");
}
w.write("\n");
// header row.
w.write(t.units+"\t");
for (ICounter counter : t.a) {
/*
* If the pattern included capturing groups then use the matched
* groups as the label for the column.
*/
final String[] groups = QueryUtil.getCapturedGroups(pattern, counter);
final String label;
if (groups != null) {
final StringBuilder sb = new StringBuilder();
for (int i = 0; i < groups.length; i++) {
final String s = groups[i];
if (i > 0)
sb.append(":");
sb.append(s);
}
label = sb.toString();
} else {
// default label is the counter name.
label = counter.getName();
}
w.write(label);
w.write("\t");
}
w.write("Timestamp\n");
}
// for each row.
for (int row = 0; row < t.nrows; row++) {
/*
* Populate array with the formatted values from each counter's
* history for the current row.
*/
final String[] valStr = new String[t.a.length];
// for each counter (in a fixed order).
for (int col = 0; col < t.ncols; col++) {
final ICounter c = t.a[col];
final IHistoryEntry e = t.data[row][col];
valStr[col] = formatter.value(c, e == null ? "" : e.getValue());
}
/*
* The time will be zero for the first row and a delta (expressed in
* the units of the history) for the remaining rows.
*
* Note: The time units are computed using floating point math and
* then converted to a display form using formatting in order to be
* able to accurately convey where a sample falls within the
* granularity of the unit (e.g., early or late in the day).
*/
final long timestamp = t.getTimestamp(row);
final String timeStr = formatter.unitsFormat
.format(((double) timestamp - t
.getTimestamp(0/* row */))
/ t.period);
w.write(timeStr + "\t");
for (String s : valStr) {
w.write(s + "\t");
}
w.write(formatter.date(timestamp) + "\n");
} // next row.
}
}