webserviceshelper.java

Oracle的J2EE Sample

/*
 * @author  : Elangovan
 * @version : 1.0
 *
 * Development Environment : Oracle9i JDeveloper
 * Name of the File        : WebServiceHelper.java
 *
 * Creation / Modification History
 *    Elangovan           26-Apr-2002        Created
 *    Elangovan           19-Aug-2003        Modified
 *
 *  This class uses Google Web APIs(TM) service for fetching the latest finance news.
 *
 *  By using this service ("Google Web APIs") you agree to be bound by the
 *  terms and conditions (the "Terms and Conditions").
 *
 *  For "Terms and Conditions" refer to http://www.google.com/apis/api_terms.html
 *
 *  Copyright (c) 2002 Google
 *
 */
package oracle.otnsamples.ibfbs.admin.helper;

import java.util.Iterator;
import java.util.Date;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.Collection;
import java.net.URLEncoder;

import oracle.otnsamples.ibfbs.utils.ConnectionParams;
import oracle.otnsamples.ibfbs.toplink.News;
import oracle.otnsamples.ibfbs.toplink.Symbol;
import oracle.otnsamples.ibfbs.toplink.Stockrate;
import oracle.otnsamples.ibfbs.admin.exception.WebServiceAccessException;

/**
 * This class access the webservices to fetch news and stockrates for the given
 * symbols. 
 * 
 * @see GoogleSearchResult.java
 * @see GoogleSearchServiceStub.java
 * @see ResultElement.java
 */
public class WebServicesHelper {

  private GoogleSearchServiceStub         search       = null;
  private XMethodsStockQuoteServiceStub   stockService = null;

  /**
   * Constructor, initializes the proxy connection properties and the news
   * search class.
   *
   * @since 1.0
   */
  public WebServicesHelper() {

    // Initialize Google Search stub
    search = new GoogleSearchServiceStub();

    // Initialize stock quote service stub
    stockService = new XMethodsStockQuoteServiceStub();
  }


  /**
   * This method retrieves the latest news for a list of  symbol by accessing
   * the news webservice.
   *
   * @param symbols list of stock symbols
   * @param maxResults maximun number of results for the list of symbols
   * @return News for all given symbols
   * @exception WebServiceAccessException if accessing webservice fails
   */
  public Collection fetchLatestNews(Collection symbols, int maxResults)
      throws WebServiceAccessException {

    ArrayList newsList    = new ArrayList();
    Date      today       = new Date();
    int       julianDate  = this.toJulian(today);
    Iterator  symIter     = symbols.iterator();
    try {

      while(symIter.hasNext()) {
        
        Symbol symbol = (Symbol)symIter.next();
        
        // Cook the search string
        String  searchQuery = new StringBuffer().append("intitle:")
                                                .append(symbol.getCompanyname())
                                                .append(" finance stock news")
                                                .append(" daterange:")
                                                .append(julianDate-30)
                                                .append("-")
                                                .append(julianDate).toString();

        // Search
        GoogleSearchResult searchResult = search.doGoogleSearch(
                                             ConnectionParams.googleSearchKey,
                                             searchQuery,
                                             new Integer(0),
                                             new Integer(maxResults),
                                             new Boolean(false),
                                             "",
                                             new Boolean(true),"","","");
                                           
        ResultElement[] result   =  searchResult.getResultElements();

        // Number of matching results
        int noofresults = searchResult.getEndIndex().intValue();
        
        // Loop throught the results, construct News instance and add them
        // to the return collection
        for (int i = 0; i < noofresults; i++) {
  
          News news = new News();
          news.setNewsdate(new java.sql.Timestamp(today.getTime()));
          news.setSymbol(symbol.getSymbol());
          news.setNewstitle(removeHTML(result[i].getTitle()));
          news.setNewsurl(URLEncoder.encode(result[i].getURL(),"UTF-8"));
  
          newsList.add(news);
        }

        searchResult = null;
        result       = null;
      }
    } catch (Exception ex) {
       ex.printStackTrace();                                   
      throw new WebServiceAccessException(" Stock News service error : "
                                          + ex.toString());

    }

    return newsList;
  }

  /**
   * This method retrieves the stockrate from the stock quote webservice.
   *
   * @param symbol stock symbol
   * @return StockRate for the symbols
   * @exception WebServiceAccessException if accessing webservice fails
   * @since 1.0
   */
  public Stockrate fetchStockRate(String symbol)
      throws WebServiceAccessException {

    float rate;
    try {

      rate = stockService.getQuote(symbol).floatValue();

    } catch (Exception ex) {
      throw new WebServiceAccessException(" Stock Quote service error : "
                                          + ex.toString());
    }
    // Construct Stock Rate
    // Increment the actual rate by 0.5 for setting the high price
    Stockrate newRate = new Stockrate();
    newRate.setSymbol(symbol);
    newRate.setStockdate(new java.sql.Timestamp(new Date().getTime()));
    newRate.setLowprice(new Double(String.valueOf(rate)));
    newRate.setHighprice(new Double(String.valueOf(rate+0.5)));
    
    return newRate;
  }

  /**
   * This method retrieves the stockrate for the list of symbols from the
   * stock quote webservice.
   *
   * @param symbol stock symbol
   * @return stockrate for the list of symbols
   * @exception WebServiceAccessException if accessing webservice fails
   * @since 1.0
   */
  public Collection fetchStockRates(Collection symbols)
      throws WebServiceAccessException {

    float     rate;
    ArrayList stockRates = new ArrayList();
    Date      today      = new Date();
    Iterator symIter = symbols.iterator();
    try {

      // For each symbol, retrieve the stock rate and populate the array list
      // with stock rates
      while(symIter.hasNext()) {
        
        Symbol symbol = (Symbol) symIter.next();
        rate = stockService.getQuote(symbol.getSymbol()).floatValue();
        // Construct a Stockrate instance and add to the return collection 
        Stockrate newRate = new Stockrate();
        newRate.setSymbol(symbol.getSymbol());
        newRate.setStockdate(new java.sql.Timestamp(today.getTime()));
        newRate.setLowprice(new Double(String.valueOf(rate)));
        newRate.setHighprice(new Double(String.valueOf(rate+0.5)));
        stockRates.add(newRate);
      }
    } catch (Exception ex) {
      throw new WebServiceAccessException(" Stock Quote service error : "
                                          + ex.toString());
    }
    return stockRates;
  }

  /**
   * This method removes HTML tags from the given string.
   *
   * @param string string with HTML tags.
   * @return string without HTML tags
   * @since 1.0
   */
  public String removeHTML(String string) {

    int start = 0, end;

    // while no more tags are found
    while (start != -1) {

      // find any string that start with <
      start = string.indexOf("<", start);

      // find the end of occurrence of the tag
      end = string.indexOf(">", start);

      // if find was successful
      if ((start != -1) && (end != -1)) {

        // remove the tag
        String first, last;

        // take out the first part, before the tag
        first = string.substring(0, start);

        // take out the last part, after the tag
        last = string.substring(end + 1);

        // merge two parts
        string = first + last;
      }
    }

    return string;
  }

  /**
   *  This method converts the given date to Julian Date format.
   *
   *  This algorithm is from Press et al., Numerical Recipes
   *  in C, 2nd ed., Cambridge University Press 1992
   *
   *  @param dt Date to be converted in Julian format
   *  @return Julian int corresponding to the given java.util.Date
   */
  private int toJulian(Date dt)   {

    GregorianCalendar cal = new GregorianCalendar();
    cal.setTime(dt);
    int year = cal.get(Calendar.YEAR);
    // Gregorian Calendar's month starts with zero
    int month = cal.get(Calendar.MONTH)+1;
    int day = cal.get(Calendar.DATE);
    int jy = year;
    if (year < 0) jy++;
    int jm = month;
    if (month > 2) jm++;
    else   {
      jy--;
      jm += 13;
    }
    int jul = (int) (java.lang.Math.floor(365.25 * jy)
              + java.lang.Math.floor(30.6001*jm) + day + 1720995.0);
    int IGREG = 15 + 31*(10+12*1582);
         // Gregorian Calendar adopted Oct. 15, 1582
    if (day + 31 * (month + 12 * year) >= IGREG)  {
       int ja = (int)(0.01 * jy);
       jul += 2 - ja + (int)(0.25 * ja);
    }

    return jul;

  }

}