company manager

package org.stock.util;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.util.HashMap;
import java.util.logging.Logger;

/**
 * Manages the companies.
 * @author Ryan Greene
 *
 */
public class CompanyManager {

    /**
     * Available exchanges.
     */
    public static final String NASDAQ_EXCHANGE = "nasdaq";
    public static final String NYSE_EXCHANGE = "nyse";

    /**
     * The logger instance, for logging.
     */
    private static final Logger logger = Logger.getLogger(CompanyManager.class.getName());

    /**
     * Base URL constants.
     */
    private static final String BASE_URL_START = "http://www.nasdaq.com/screening/companies-by-name.aspx?letter=0&exchange=";
    private static final String BASE_URL_STOP = "&render=download";

    /**
     * Attribute constants.
     */
    private static final String ATTRIBUTE_SPLIT_REGEX = "\",\"";

    private static final int SYMBOL_ATTRIBUTE = 0;
    private static final int NAME_ATTRIBUTE = 1;
    private static final int LAST_SALE_ATTRIBUTE = 2;
    private static final int MARKET_CAP_ATTRIBUTE = 3;
    private static final int ADR_TSO_ATTRIBUTE = 4;
    private static final int IPO_YEAR_ATTRIBUTE = 5;
    private static final int SECTOR_ATTRIBUTE = 6;
    private static final int INDUSTRY_ATTRIBUTE = 7;
    private static final int SUMMARY_QUOTE_ATTRIBUTE = 8;

    /**
     * Contains all the companies being managed with the key being their symbol or ticker.
     */
    private static HashMap<String, Company> companies = null;

    /**
     * Gets the company with the specified symbol.
     * @param symbol The symbol.
     * @return The company.
     */
    public static Company getCompany(String symbol) {
        return companies.get(symbol);
    }

    /**
     * Initiates the company manager with the specified exchange.
     * @param exchange The exchange.
     * @throws IOException
     * @throws IllegalStateException if the companies have already been loaded.
     */
    public static void init(final String exchange) throws IOException {
        if (companies != null) {
            throw new IllegalStateException("Companies already loaded.");
        }
        logger.info("Initiating company manager for the exchange: " + exchange);
        companies = new HashMap<String, Company>();
        URL url = new URL(BASE_URL_START + exchange + BASE_URL_STOP);
        URLConnection connection = url.openConnection();
        BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
        try {
            String line = reader.readLine();
            while ((line = reader.readLine()) != null) {
                String[] attributes = line.split(ATTRIBUTE_SPLIT_REGEX);

                String symbol = attributes[SYMBOL_ATTRIBUTE];
                String name = attributes[NAME_ATTRIBUTE];
                double lastSale = attributes[LAST_SALE_ATTRIBUTE].equals("n/a") ? -1 : Double.parseDouble(attributes[LAST_SALE_ATTRIBUTE]);
                double marketCap = attributes[MARKET_CAP_ATTRIBUTE].equals("n/a") ? -1 : Double.parseDouble(attributes[MARKET_CAP_ATTRIBUTE]);
                String adrTso = attributes[ADR_TSO_ATTRIBUTE];
                int ipoYear = attributes[IPO_YEAR_ATTRIBUTE].equals("n/a") ? -1 : Integer.parseInt(attributes[IPO_YEAR_ATTRIBUTE]);
                String sector = attributes[SECTOR_ATTRIBUTE];
                String industry = attributes[INDUSTRY_ATTRIBUTE];
                String summaryQuote = attributes[SUMMARY_QUOTE_ATTRIBUTE];

                Company company = Company.createCompany(symbol, name, lastSale, marketCap, adrTso, ipoYear, sector, industry, summaryQuote);
                companies.put(symbol, company);
            }
        } finally {
            if (reader != null) {
                reader.close();
            }
        }
        logger.info("Loaded " + companies.size() + " companies.");
    }

}