com.bah.bahdit.main.search.Search.java Source code

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Here is the source code for com.bah.bahdit.main.search.Search.java

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/**
 * Copyright 2012 Booz Allen Hamilton. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  Booz Allen Hamilton 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.
 */
/**
 * 
 * Cloud Analytics Intern Proj. 2012
 * Main Search Controller
 * Search.java
 * 
 */

package com.bah.bahdit.main.search;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Properties;

import javax.servlet.ServletContext;

import org.apache.accumulo.core.client.AccumuloException;
import org.apache.accumulo.core.client.AccumuloSecurityException;
import org.apache.accumulo.core.client.Connector;
import org.apache.accumulo.core.client.Instance;
import org.apache.accumulo.core.client.ZooKeeperInstance;

import com.bah.bahdit.main.plugins.fulltextindex.data.SearchResults;
import com.bah.bahdit.main.plugins.index.Index;
import com.google.inject.Guice;
import com.google.inject.Injector;
import com.sun.org.apache.commons.logging.Log;
import com.sun.org.apache.commons.logging.LogFactory;

/**
 * 
 * Main search controller object for bahdit. A connection is established
 * and held. A search can be executed by calling search. Configuration
 * for a particular index happens in the search module.
 *
 */
public class Search {

    private static Log log = LogFactory.getLog(Search.class);

    public static final String CONFIGURATION_FILE = "/properties.conf";

    public static final String QUERY = "QUERY";
    public static final String MAX_NGRAMS = "MAX_NGRAMS";
    public static final String NUM_RESULTS = "NUM_RESULTS";
    public static final String PAGERANK_TABLE = "PAGERANK_TABLE";
    public static final String DOMAIN_STOP = "DOMAIN_STOP";
    public static final String GENERAL_STOP = "GENERAL_STOP";

    public static final String INDEX = "INDEX";
    public static final String INSTANCE_NAME = "INSTANCE_NAME";
    public static final String USERNAME = "USERNAME";
    public static final String PASSWORD = "PASSWORD";
    public static final String ZK_SERVERS = "ZK_SERVERS";
    public static final String PAGE = "PAGE";

    private Index index = null;
    private Connector conn = null;
    private Properties properties = null;

    /**
     * 
     * The main search object that gets a connection and sets up 
     * the Index and the configurations.
     * 
     * @param context - a servlet context from which the 
     *                search will grab its files from
     * @param indexToUse - text constant found in the search module to use.
     * @throws IOException 
     */
    public Search(ServletContext context, String indexToUse) throws IOException {
        properties = new Properties();
        properties.load(context.getResourceAsStream(CONFIGURATION_FILE));
        Injector injector = Guice.createInjector(new SearcherModule(indexToUse));
        this.index = injector.getInstance(Index.class);
        this.conn = connect();
        index.configure(conn, properties, context);
    }

    /**
     * 
     * Calls the Index's search with a particular query object
     * 
     * @param query
     * @param page
     * @param resultsPerPage
     * @return
     */
    public SearchResults search(Object query, int page, int resultsPerPage) {
        return index.search(query, page, resultsPerPage);
    }

    /**
     * 
     * Gets the index's configuration
     * 
     * @param results - returns an arraylist of object 
     *                visualization form the index
     * @return
     */
    public ArrayList<?> getVisualizations(SearchResults results) {
        return index.getVisualizations(results);
    }

    /**
     * 
     * Connects to an accumulo instance in the config file 
     * then returns that connection
     * 
     * @return
     */
    private Connector connect() {
        Connector connector = null;
        String instanceName = properties.getProperty(INSTANCE_NAME);
        String zkServerNames = properties.getProperty(ZK_SERVERS);
        String user = properties.getProperty(USERNAME);
        String password = properties.getProperty(PASSWORD);

        Instance inst = new ZooKeeperInstance(instanceName, zkServerNames);

        try {
            connector = inst.getConnector(user, password.getBytes());
        } catch (AccumuloException e) {
            log.error(e.getMessage());
        } catch (AccumuloSecurityException e) {
            log.error(e.getMessage());
        }

        return connector;
    }
}