Java tutorial
/* * Copyright 2011 Facebook, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.facebook.tsdb.tsdash.server.data; import java.util.ArrayList; import org.json.simple.JSONArray; import org.json.simple.JSONObject; import com.facebook.tsdb.tsdash.server.model.DataPoint; import com.facebook.tsdb.tsdash.server.model.Metric; import com.facebook.tsdb.tsdash.server.model.TagsArray; public class DataTable { private final Metric[] metrics; public DataTable(Metric[] metrics) { this.metrics = metrics; } @SuppressWarnings("unchecked") private JSONObject newColumn(String label, String type) { JSONObject col = new JSONObject(); col.put("label", label); col.put("type", type); return col; } private String renderLineTitle(Metric metric, TagsArray tags) { String suffix = metric.isRate() ? " /s" : ""; return metric.getName() + ": " + tags.getTitle() + suffix; } @SuppressWarnings("unchecked") private JSONArray generateColumns() { JSONArray cols = new JSONArray(); cols.add(newColumn("Date", "datetime")); for (Metric metric : metrics) { for (TagsArray timeSeries : metric.timeSeries.keySet()) { cols.add(newColumn(renderLineTitle(metric, timeSeries), "number")); } } return cols; } @SuppressWarnings("unchecked") private JSONObject newDataCell(double value) { JSONObject cell = new JSONObject(); cell.put("v", value); return cell; } @SuppressWarnings("unchecked") private JSONObject newTsCell(long ts) { JSONObject cell = new JSONObject(); cell.put("v", ts * 1000); return cell; } @SuppressWarnings("unchecked") private JSONArray generateRows() { // figure out the entire time series ArrayList<Long> timeSeries = new ArrayList<Long>(); for (Metric metric : metrics) { for (TagsArray t : metric.timeSeries.keySet()) { timeSeries = TimeSeries.merge(timeSeries, metric.timeSeries.get(t)); } } JSONObject nullCell = new JSONObject(); JSONArray rows = new JSONArray(); for (long ts : timeSeries) { JSONObject row = new JSONObject(); JSONArray cells = new JSONArray(); cells.add(newTsCell(ts)); for (Metric metric : metrics) { for (TagsArray t : metric.timeSeries.keySet()) { ArrayList<DataPoint> points = metric.timeSeries.get(t); if (points.size() > 0 && points.get(0).ts == ts) { cells.add(newDataCell(points.get(0).value)); points.remove(0); } else { cells.add(nullCell); } } } row.put("c", cells); rows.add(row); } return rows; } @SuppressWarnings("unchecked") public JSONObject toJSONObject() { JSONObject result = new JSONObject(); result.put("cols", generateColumns()); result.put("rows", generateRows()); return result; } }