Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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 org.apache.solr.analytics; import java.io.ByteArrayInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.nio.charset.StandardCharsets; import java.util.ArrayList; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; import java.util.Scanner; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import javax.xml.xpath.XPathConstants; import javax.xml.xpath.XPathExpressionException; import javax.xml.xpath.XPathFactory; import org.apache.commons.lang.StringUtils; import org.apache.lucene.util.IOUtils; import org.apache.solr.SolrTestCaseJ4; import org.apache.solr.analytics.util.MedianCalculator; import org.apache.solr.analytics.util.PercentileCalculator; import org.apache.solr.request.SolrQueryRequest; import org.junit.AfterClass; import org.junit.BeforeClass; import org.w3c.dom.Document; import org.xml.sax.InputSource; import org.xml.sax.SAXException; import com.google.common.collect.ObjectArrays; public class AbstractAnalyticsStatsTest extends SolrTestCaseJ4 { protected static final String[] BASEPARMS = new String[] { "q", "*:*", "indent", "true", "olap", "true", "rows", "0" }; protected static final HashMap<String, Object> defaults = new HashMap<>(); public static enum VAL_TYPE { INTEGER("int"), LONG("long"), FLOAT("float"), DOUBLE("double"), STRING("str"), DATE("date"); private VAL_TYPE(final String text) { this.text = text; } private final String text; @Override public String toString() { return text; } } static private Document doc; static private XPathFactory xPathFact; static private String rawResponse; @BeforeClass public static void beforeClassAbstractAnalysis() { xPathFact = XPathFactory.newInstance(); } @AfterClass public static void afterClassAbstractAnalysis() { xPathFact = null; doc = null; rawResponse = null; defaults.clear(); } public static void setResponse(String response) throws ParserConfigurationException, IOException, SAXException { DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); factory.setNamespaceAware(true); // never forget this! DocumentBuilder builder = factory.newDocumentBuilder(); doc = builder.parse(new InputSource(new ByteArrayInputStream(response.getBytes(StandardCharsets.UTF_8)))); rawResponse = response; } protected String getRawResponse() { return rawResponse; } public Object getStatResult(String section, String name, VAL_TYPE type) throws XPathExpressionException { // Construct the XPath expression. The form better not change or all these will fail. StringBuilder sb = new StringBuilder("/response/lst[@name='stats']/lst[@name='").append(section) .append("']"); // This is a little fragile in that it demands the elements have the same name as type, i.e. when looking for a // VAL_TYPE.DOUBLE, the element in question is <double name="blah">47.0</double>. sb.append("/").append(type.toString()).append("[@name='").append(name).append("']"); String val = xPathFact.newXPath().compile(sb.toString()).evaluate(doc, XPathConstants.STRING).toString(); try { switch (type) { case INTEGER: return Integer.parseInt(val); case DOUBLE: return Double.parseDouble(val); case FLOAT: return Float.parseFloat(val); case LONG: return Long.parseLong(val); case STRING: assertTrue(rawResponse, val != null && val.length() > 0); return val; case DATE: assertTrue(rawResponse, val != null && val.length() > 0); return val; } } catch (Exception e) { e.printStackTrace(); fail("Caught exception in getStatResult, xPath = " + sb.toString() + " \nraw data: " + rawResponse); } fail("Unknown type used in getStatResult"); return null; // Really can't get here, but the compiler thinks we can! } public <T extends Number & Comparable<T>> Double calculateNumberStat(ArrayList<T> list, String stat) { Double result; if (stat.equals("median")) { result = MedianCalculator.getMedian(list); } else if (stat.equals("mean")) { double d = 0; for (T element : list) { d += element.doubleValue(); } result = Double.valueOf(d / list.size()); } else if (stat.equals("sum")) { double d = 0; for (T element : list) { d += element.doubleValue(); } result = Double.valueOf(d); } else if (stat.equals("sumOfSquares")) { double d = 0; for (T element : list) { d += element.doubleValue() * element.doubleValue(); } result = Double.valueOf(d); } else if (stat.equals("stddev")) { double sum = 0; double sumSquares = 0; for (T element : list) { sum += element.doubleValue(); sumSquares += element.doubleValue() * element.doubleValue(); } result = Math.sqrt(sumSquares / list.size() - sum * sum / (list.size() * list.size())); } else { throw new IllegalArgumentException(); } return result; } public <T extends Comparable<T>> Object calculateStat(ArrayList<T> list, String stat) { Object result; if (stat.contains("perc_")) { double[] perc = new double[] { Double.parseDouble(stat.substring(5)) / 100 }; result = PercentileCalculator.getPercentiles(list, perc).get(0); } else if (stat.equals("count")) { result = Long.valueOf(list.size()); } else if (stat.equals("unique")) { HashSet<T> set = new HashSet<>(); set.addAll(list); result = Long.valueOf((long) set.size()); } else if (stat.equals("max")) { Collections.sort(list); result = list.get(list.size() - 1); } else if (stat.equals("min")) { Collections.sort(list); result = list.get(0); } else { result = null; } return result; } @SuppressWarnings("unchecked") public <T extends Comparable<T>> Long calculateMissing(ArrayList<T> list, String type) { T def = (T) defaults.get(type); long miss = 0; for (T element : list) { if (element.compareTo(def) == 0) { miss++; } } return Long.valueOf(miss); } public static SolrQueryRequest request(String... args) { return SolrTestCaseJ4.req(ObjectArrays.concat(BASEPARMS, args, String.class)); } public static String[] fileToStringArr(Class<?> clazz, String fileName) throws FileNotFoundException { InputStream in = clazz.getResourceAsStream(fileName); if (in == null) throw new FileNotFoundException("Resource not found: " + fileName); Scanner file = new Scanner(in, "UTF-8"); try { ArrayList<String> strList = new ArrayList<>(); while (file.hasNextLine()) { String line = file.nextLine(); line = line.trim(); if (StringUtils.isBlank(line) || line.startsWith("#")) { continue; } String[] param = line.split("="); strList.add(param[0]); strList.add(param[1]); } return strList.toArray(new String[0]); } finally { IOUtils.closeWhileHandlingException(file, in); } } }