Java tutorial
/** * SearchConnection.java * Author: Francesco Rosso (rosso@eurix.it) * Contributors: Philip Kahle (philip.kahle@uibk.ac.at) * * This file is part of PrestoPRIME Preservation Platform (P4). * * Copyright (C) 2009-2012 EURIX Srl, Torino, Italy * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package eu.prestoprime.p4gui.connection; import java.io.BufferedReader; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.Reader; import java.io.StringWriter; import java.io.Writer; import java.util.ArrayList; import java.util.Collections; import java.util.HashMap; import java.util.Map; import java.util.Map.Entry; import javax.xml.bind.JAXBException; import javax.xml.bind.Unmarshaller; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.methods.HttpRequestBase; import org.apache.http.util.EntityUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import eu.prestoprime.model.ModelUtils; import eu.prestoprime.model.ModelUtils.P4JAXBPackage; import eu.prestoprime.model.search.SearchResults; import eu.prestoprime.p4gui.model.P4Service; import eu.prestoprime.p4gui.util.URLUtils; import eu.prestoprime.search.SearchConstants; public abstract class SearchConnection { private static final Logger logger = LoggerFactory.getLogger(SearchConnection.class); private static final String QUICK_URI = "/search/quick"; private static final String ADVANCED_URI = "/search/advanced"; private static final String SUGGEST_URI = "/search/suggest"; public static ArrayList<String> searchByDC(P4Service service, String title, String description, String format, String identifier) { ArrayList<String> records = new ArrayList<String>(); try { String path = service.getURL() + "/search/?" + "title=" + title + "&description=" + description + "&format=" + format + "&identifier=" + identifier; P4HttpClient client = new P4HttpClient(service.getUserID()); HttpRequestBase request = new HttpGet(path); HttpResponse response = client.executeRequest(request); HttpEntity entity = response.getEntity(); if (entity != null) { InputStream is = entity.getContent(); BufferedReader reader = new BufferedReader(new InputStreamReader(is)); String line = null; while ((line = reader.readLine()) != null) { records.add(line); } is.close(); } EntityUtils.consume(entity); } catch (Exception e) { e.printStackTrace(); } Collections.reverse(records); return records; } public static String searchByOaiPmh(P4Service service, String params) { String string = null; try { params = params.replaceAll("--", "&"); String path = service.getURL() + "/search/oai?" + params; P4HttpClient client = new P4HttpClient(service.getUserID()); HttpRequestBase request = new HttpGet(path); HttpResponse response = client.executeRequest(request); HttpEntity entity = response.getEntity(); if (entity != null) { InputStream is1 = entity.getContent(); BufferedReader reader = new BufferedReader(new InputStreamReader(is1)); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line); } string = sb.toString(); is1.close(); } EntityUtils.consume(entity); } catch (IOException e) { e.printStackTrace(); } return string; } private static SearchResults solrSearch(final P4Service service, final String searchUri, String query, final String from, final String resultCount, final String sortField, final String sortAsc, final Map<String, String> facetMap) { HashMap<String, String> urlParamMap = new HashMap<>(); urlParamMap.put("queryTerms", query); urlParamMap.put("from", from); urlParamMap.put("resultCount", resultCount); urlParamMap.put("sortAsc", sortAsc); urlParamMap.put("sortField", sortField); urlParamMap.put("facetFilters", wrapParams(facetMap)); final String path = service.getURL() + searchUri + URLUtils.buildUrlParamString(urlParamMap); SearchResults results = new SearchResults(); Unmarshaller unmarshaller = null; String resultString = null; try { logger.debug("Query to P4WS:\n" + path); P4HttpClient client = new P4HttpClient(service.getUserID()); client.getParams().setParameter("http.protocol.content-charset", "UTF-8"); HttpRequestBase request = new HttpGet(path); HttpResponse response = client.executeRequest(request); HttpEntity entity = response.getEntity(); if (entity != null) { InputStream is = entity.getContent(); BufferedReader reader = new BufferedReader(new InputStreamReader(is)); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line); } resultString = sb.toString(); is.close(); } EntityUtils.consume(entity); unmarshaller = ModelUtils.getUnmarshaller(P4JAXBPackage.CONF); results = (SearchResults) unmarshaller.unmarshal(new ByteArrayInputStream(resultString.getBytes())); } catch (JAXBException | IOException e) { String message = e.getMessage() + " - "; logger.error(e.getMessage()); if (e instanceof JAXBException) { message += "The returned xml from P4WS was not a valid searchresult."; } else { message += "P4WS could not be accessed."; } results.setErrorMessage(message); } return results; } /** * encode all facet values into a string. * * @param facetMap * @return */ private static String wrapParams(Map<String, String> facetMap) { StringBuilder sb = new StringBuilder(); for (Entry<String, String> e : facetMap.entrySet()) { if (sb.length() > 0) { sb.append(SearchConstants.KV_SEP); } if (e.getValue() != null && !filter(e.getValue()).isEmpty()) { sb.append(filter(e.getKey()) + SearchConstants.KV_CON + filter(e.getValue())); } } return sb.toString(); } private static String filter(String s) { return s.replace(SearchConstants.KV_CON, "").replace(SearchConstants.KV_SEP, ""); } public static SearchResults simpleSolrSearch(P4Service service, final String query, final String from, final String resultCount, final String sortField, final String sortAsc, final Map<String, String> facetMap) { final SearchResults results = solrSearch(service, QUICK_URI, query, from, resultCount, sortField, sortAsc, facetMap); return results; } public static SearchResults advancedSolrSearch(P4Service service, HashMap<String, String> queryMap, final String from, final String resultCount, final String sortField, final String sortAsc, final Map<String, String> facetMap) { String query = wrapParams(queryMap); final SearchResults results = solrSearch(service, ADVANCED_URI, query, from, resultCount, sortField, sortAsc, facetMap); return results; } public static String solrSuggest(P4Service service, final String term) { Writer writer = new StringWriter(); String results = ""; try { StringBuilder sb = new StringBuilder(); sb.append(service.getURL()); sb.append(SUGGEST_URI); sb.append("?term="); sb.append(term); String path = sb.toString(); logger.debug("Query to P4WS:\n" + path); P4HttpClient client = new P4HttpClient(service.getUserID()); client.getParams().setParameter("http.protocol.content-charset", "UTF-8"); HttpRequestBase request = new HttpGet(path); HttpResponse response = client.executeRequest(request); HttpEntity entity = response.getEntity(); if (entity != null) { InputStream is = entity.getContent(); if (is != null) { char[] buffer = new char[1024]; Reader reader = new BufferedReader(new InputStreamReader(is, "UTF-8")); int n; while ((n = reader.read(buffer)) != -1) { writer.write(buffer, 0, n); } is.close(); } } results = writer.toString(); EntityUtils.consume(entity); writer.close(); } catch (Exception e) { logger.error(e.getMessage()); logger.error("Either the query was invalid or P4WS could not be accessed."); results = null; } return results; } }