Java tutorial
/********************************************************************************** * $URL: https://source.sakaiproject.org/svn/search/trunk/search-impl/impl/src/java/org/sakaiproject/search/component/service/impl/SearchListResponseImpl.java $ * $Id: SearchListResponseImpl.java 105078 2012-02-24 23:00:38Z ottenhoff@longsight.com $ *********************************************************************************** * * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009 The Sakai Foundation * * Licensed under the Educational Community 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.opensource.org/licenses/ECL-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.sakaiproject.search.component.service.impl; import java.io.IOException; import java.io.StringReader; import java.util.ArrayList; import java.util.Collection; import java.util.Iterator; import java.util.List; import java.util.ListIterator; import java.util.Stack; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.lucene.analysis.Analyzer; import org.apache.lucene.search.Query; import org.sakaiproject.search.api.EntityContentProducer; import org.sakaiproject.search.api.PortalUrlEnabledProducer; import org.sakaiproject.search.api.SearchIndexBuilder; import org.sakaiproject.search.api.SearchList; import org.sakaiproject.search.api.SearchResult; import org.sakaiproject.search.api.SearchService; import org.sakaiproject.search.filter.SearchItemFilter; import org.xml.sax.Attributes; import org.xml.sax.ContentHandler; import org.xml.sax.InputSource; import org.xml.sax.Locator; import org.xml.sax.SAXException; import org.xml.sax.XMLReader; import org.xml.sax.helpers.AttributesImpl; import org.xml.sax.helpers.XMLReaderFactory; /** * @author ieb */ public class SearchListResponseImpl implements SearchList, ContentHandler { private static Log log = LogFactory.getLog(SearchListResponseImpl.class); private Query query; private int start = 0; private int end = 500; private Analyzer analyzer; private SearchItemFilter filter; private SearchIndexBuilder searchIndexBuilder; private SearchService searchService; private List<SearchResult> resultsList; private Stack<StackElement> stack; private Object errorMessage = null; private int size; private int fullsize; public SearchListResponseImpl(String response, Query query, int start, int end, Analyzer analyzer, SearchItemFilter filter, SearchIndexBuilder searchIndexBuilder, SearchService searchService) throws SAXException, IOException { this.query = query; this.start = start; this.end = end; this.analyzer = analyzer; this.filter = filter; this.searchIndexBuilder = searchIndexBuilder; this.searchService = searchService; if (log.isDebugEnabled()) { log.debug("search response: [" + response + "]"); } XMLReader xr = XMLReaderFactory.createXMLReader(); xr.setContentHandler(this); InputSource is = new InputSource(new StringReader(response)); xr.parse(is); if (errorMessage != null) { log.error("Failed to perform remote request, remote exception was: \n" + errorMessage); throw new IOException("Failed to perform remote request "); } } /** * @{inheritDoc} */ public Iterator<SearchResult> iterator(final int startAt) { return new Iterator<SearchResult>() { int counter = Math.max(startAt, start) - start; public boolean hasNext() { return counter < resultsList.size(); } public SearchResult next() { int thisHit = counter; counter++; if (log.isDebugEnabled()) { log.debug("Iterator Getting item " + thisHit); } SearchResult ret = (SearchResult) resultsList.get(thisHit); String url = checkUrl(ret.getReference()); if (url != null) ret.setUrl(url); return filter.filter(ret); } public void remove() { throw new UnsupportedOperationException("Not Implemented"); } /** * Check the results url before returning * @param reference * @return */ private String checkUrl(String reference) { log.debug("checkUrl(" + reference); if (searchIndexBuilder != null) { EntityContentProducer ecp = searchIndexBuilder.newEntityContentProducer(reference); if (ecp == null) return null; if (PortalUrlEnabledProducer.class.isAssignableFrom(ecp.getClass())) return ecp.getUrl(reference); } return null; } }; } public int size() { return size; } public int getFullSize() { return fullsize; } public boolean isEmpty() { return (size() == 0); } public boolean contains(Object arg0) { throw new UnsupportedOperationException("Not Implemented"); } public Iterator<SearchResult> iterator() { return iterator(0); } public Object[] toArray() { Object[] o = new Object[size()]; for (int i = 0; i < o.length; i++) { o[i] = filter.filter((SearchResult) resultsList.get(i)); } return o; } public Object[] toArray(Object[] arg0) { if (arg0 instanceof SearchResult[]) { return toArray(); } return null; } public boolean add(SearchResult arg0) { throw new UnsupportedOperationException("Not Implemented"); } public boolean remove(Object arg0) { throw new UnsupportedOperationException("Not Implemented"); } public boolean containsAll(Collection arg0) { throw new UnsupportedOperationException("Not Implemented"); } public boolean addAll(Collection arg0) { throw new UnsupportedOperationException("Not Implemented"); } public boolean addAll(int arg0, Collection arg1) { throw new UnsupportedOperationException("Not Implemented"); } public boolean removeAll(Collection arg0) { throw new UnsupportedOperationException("Not Implemented"); } public boolean retainAll(Collection arg0) { throw new UnsupportedOperationException("Not Implemented"); } public void clear() { throw new UnsupportedOperationException("Not Implemented"); } public SearchResult get(int arg0) { SearchResult sr = (SearchResult) resultsList.get(arg0); String url = checkUrl(sr.getReference()); if (url != null) sr.setUrl(url); return filter.filter(sr); } public SearchResult set(int arg0, SearchResult arg1) { throw new UnsupportedOperationException("Not Implemented"); } public void add(int arg0, SearchResult arg1) { throw new UnsupportedOperationException("Not Implemented"); } public SearchResult remove(int arg0) { throw new UnsupportedOperationException("Not Implemented"); } public int indexOf(Object arg0) { throw new UnsupportedOperationException("Not Implemented"); } public int lastIndexOf(Object arg0) { throw new UnsupportedOperationException("Not Implemented"); } public ListIterator<SearchResult> listIterator() { throw new UnsupportedOperationException("Not Implemented"); } public ListIterator<SearchResult> listIterator(int arg0) { throw new UnsupportedOperationException("Not Implemented"); } public List<SearchResult> subList(int arg0, int arg1) { throw new UnsupportedOperationException("Not Implemented"); } public int getStart() { return start; } public void characters(char[] ch, int start, int length) throws SAXException { StackElement se = (StackElement) stack.peek(); se.append(ch, start, length); } public void endDocument() throws SAXException { } public void endElement(String uri, String localName, String qName) throws SAXException { if (log.isDebugEnabled()) { log.debug("End Element uri:" + uri + " ln:" + localName + " qn:" + qName); } StackElement se = (StackElement) stack.pop(); if ("error".equals(localName)) { errorMessage = se.getContent(); log.error("Error Message found from remote search " + errorMessage); } else if ("result".equals(localName)) { SearchResult sr; try { sr = new SearchResultResponseImpl(se.getAttributes(), query, analyzer, searchIndexBuilder, searchService); } catch (IOException e) { throw new SAXException(e.getMessage(), e); } resultsList.add(sr); if (log.isDebugEnabled()) { log.debug("Added Search Result " + resultsList.size()); } } else if ("results".equals(localName)) { fullsize = Integer.parseInt(se.getAttributes().getValue("fullsize")); start = Integer.parseInt(se.getAttributes().getValue("start")); size = Integer.parseInt(se.getAttributes().getValue("size")); } } public void endPrefixMapping(String prefix) throws SAXException { } public void ignorableWhitespace(char[] ch, int start, int length) throws SAXException { } public void processingInstruction(String target, String data) throws SAXException { } public void setDocumentLocator(Locator locator) { } public void skippedEntity(String name) throws SAXException { } public void startDocument() throws SAXException { resultsList = new ArrayList<SearchResult>(); stack = new Stack<StackElement>(); } public void startElement(String uri, String localName, String qName, Attributes atts) throws SAXException { if (log.isDebugEnabled()) { log.debug("Start Element uri:" + uri + " ln:" + localName + " qn:" + qName); } StackElement se = new StackElement(uri, localName, qName, atts); stack.push(se); } public void startPrefixMapping(String prefix, String uri) throws SAXException { } public class StackElement { private String uri; private String localName; private String name; private Attributes atts; private StringBuilder content; public StackElement(String uri, String localName, String name, Attributes atts) { this.uri = uri; this.localName = localName; this.name = name; this.atts = new AttributesImpl(atts); this.content = new StringBuilder(); } public Attributes getAttributes() { return atts; } public String getContent() { return content.toString(); } public void append(char[] ch, int start, int length) { content.append(ch, start, length); } } /** * Check the results url before returning * @param reference * @return */ private String checkUrl(String reference) { if (searchIndexBuilder != null) { EntityContentProducer ecp = searchIndexBuilder.newEntityContentProducer(reference); if (ecp == null) return null; ; if (PortalUrlEnabledProducer.class.isAssignableFrom(ecp.getClass())) return ecp.getUrl(reference); } return null; } }