Java tutorial
/** * Copyright (C) 2014 Dasasian (damith@dasasian.com) * * 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.dasasian.chok.lucene; import org.apache.hadoop.io.MapWritable; import org.apache.hadoop.ipc.VersionedProtocol; import java.io.IOException; /** * The public interface to the back end LuceneServer. These are all the * methods that the Hadoop RPC will call. */ public interface ILuceneServer extends VersionedProtocol { /** * Returns all Hits that match the query. This might be significant slower as * {@link #search(QueryWritable, DocumentFrequencyWritable, String[], long, int)} since we * replace count with Integer.MAX_VALUE. * * @param query The query to run. * @param freqs Term frequency information for term weighting. * @param shardNames A array of shard names to search in. * @param timeout How long the query is allowed to run before getting interrupted * @return A list of hits from the search. * @throws IOException If the search had a problem reading files. */ public HitsMapWritable search(QueryWritable query, DocumentFrequencyWritable freqs, String[] shardNames, long timeout) throws IOException; /** * @param query The query to run. * @param freqs Term frequency information for term weighting. * @param shardNames A array of shard names to search in. * @param timeout How long the query is allowed to run before getting interrupted * @param count The top n high score hits. * @return A list of hits from the search. * @throws IOException If the search had a problem reading files. */ public HitsMapWritable search(QueryWritable query, DocumentFrequencyWritable freqs, String[] shardNames, long timeout, int count) throws IOException; /** * Sorts the returned hits based on the sort parameter. * * @param query The query to run. * @param freqs Term frequency information for term weighting. * @param shardNames A array of shard names to search in. * @param timeout How long the query is allowed to run before getting interrupted * @param count The top n high score hits. * @param sort sort criteria for returned hits * @return A list of hits from the search. * @throws IOException If the search had a problem reading files. */ public HitsMapWritable search(QueryWritable query, DocumentFrequencyWritable freqs, String[] shardNames, long timeout, int count, SortWritable sort) throws IOException; /** * Sorts the returned hits based on the sort parameter. * * @param query The query to run. * @param freqs Term frequency information for term weighting. * @param shardNames A array of shard names to search in. * @param timeout How long the query is allowed to run before getting interrupted * @param count The top n high score hits. * @param filter A query filter. * @return A list of hits from the search. * @throws IOException If the search had a problem reading files. */ public HitsMapWritable search(QueryWritable query, DocumentFrequencyWritable freqs, String[] shardNames, long timeout, int count, FilterWritable filter) throws IOException; /** * Sorts the returned hits based on the sort parameter. * * @param query The query to run. * @param freqs Term frequency information for term weighting. * @param shardNames A array of shard names to search in. * @param timeout How long the query is allowed to run before getting interrupted * @param count The top n high score hits. * @param sort sort criteria for returned hits * @param filter A query filter. * @return A list of hits from the search. * @throws IOException If the search had a problem reading files. */ public HitsMapWritable search(QueryWritable query, DocumentFrequencyWritable freqs, String[] shardNames, long timeout, int count, SortWritable sort, FilterWritable filter) throws IOException; /** * Returns the number of documents a term occurs in. In a distributed search * environment, we need to get this first and then query all nodes again with * this information to ensure we compute TF IDF correctly. See * <a href="http://lucene.apache.org/java/2_3_0/api/org/apache/lucene/search/Similarity.html">Lucene's Similarity</a> * * @param input TODO is this really just a Lucene query? * @param shards The shards to search in. * @return A list of hits from the search. * @throws IOException If the search had a problem reading files. */ public DocumentFrequencyWritable getDocFreqs(QueryWritable input, String[] shards) throws IOException; /** * Returns only the requested fields of a lucene document. The fields are returned * as a map. * * @param shards The shards to ask for the document. * @param docId The document that is desired. * @param fields The fields to return. * @return details of the document * @throws IOException when and error occurs */ public MapWritable getDetails(String[] shards, int docId, String[] fields) throws IOException; /** * Returns the lucene document. Each field:value tuple of the lucene document * is inserted into the returned map. In most cases * {@link #getDetails(String[], int, String[])} would be a better choice for * performance reasons. * * @param shards The shards to ask for the document. * @param docId The document that is desired. * @return details of the document * @throws IOException when and error occurs */ public MapWritable getDetails(String[] shards, int docId) throws IOException; /** * Returns the number of documents that match the given query. This the * fastest way in case you just need the number of documents. Note that the * number of matching documents is also included in HitsMapWritable. * * @param query the query * @param shards the shards * @param timeout How long the query is allowed to run before getting interrupted * @return number of documents * @throws IOException when and error occurs */ public int getResultCount(QueryWritable query, String[] shards, long timeout) throws IOException; /** * Returns the number of documents that match the given query. This the * fastest way in case you just need the number of documents. Note that the * number of matching documents is also included in HitsMapWritable. * * @param query the query * @param filter the filter * @param shards the shards * @param timeout How long the query is allowed to run before getting interrupted * @return number of documents * @throws IOException when and error occurs */ public int getResultCount(QueryWritable query, FilterWritable filter, String[] shards, long timeout) throws IOException; }