StockPriceDownloader.java

package org.jetbrains.mps.samples.money.runtime;

/*Generated by MPS */

import java.util.Map;
import java.util.List;
import jetbrains.mps.internal.collections.runtime.MapSequence;
import java.util.HashMap;
import jetbrains.mps.internal.collections.runtime.ListSequence;
import java.util.ArrayList;
import java.net.URL;
import java.io.InputStream;
import jetbrains.mps.util.URLUtil;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.text.SimpleDateFormat;
import java.util.StringTokenizer;
import java.text.ParseException;
import java.net.MalformedURLException;
import java.io.IOException;

public final class StockPriceDownloader {
  private static StockPriceDownloader instance = new StockPriceDownloader();

  public static StockPriceDownloader getInstance() {
    return instance;
  }

  private StockPriceDownloader() {
  }

  private Map<String, List<DailyStockPrice>> priceCache = MapSequence.fromMap(new HashMap<String, List<DailyStockPrice>>());

  public void clearCache() {
    MapSequence.fromMap(priceCache).clear();
  }

  public boolean isValidStockSymbol(String symbol) {
    return getCurrentPrice(symbol) != null;
  }

  public Money getCurrentPrice(String symbol) {
    if ((symbol != null && symbol.length() > 0)) {
      try {
        List<DailyStockPrice> prices = MapSequence.fromMap(priceCache).get(symbol);
        if (prices == null) {
          prices = ListSequence.fromList(new ArrayList<DailyStockPrice>());
          URL url = new URL("http://ichart.finance.yahoo.com/table.csv?s=" + symbol);
          InputStream stream = URLUtil.openStream(url);
          BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
          String line;
          boolean header = true;
          SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
          while ((line = reader.readLine()) != null) {
            if (!(header)) {
              String[] item = new String[7];
              StringTokenizer tokenizer = new StringTokenizer(line, ",");
              try {
                for (int i = 0; i < 7; i++) {
                  item[i] = trim_54jj5w_a0a0a0a2a0a7a1a0a0a21(tokenizer.nextToken());
                }
                DailyStockPrice price = new DailyStockPrice(dateFormat.parse(item[0]), item[1], item[2], item[3], item[4], item[5], item[6]);
                ListSequence.fromList(prices).addElement(price);

              } catch (ParseException e) {
                // date parsing error 
                return null;
              } catch (IndexOutOfBoundsException e) {
                // line parsing error 
                return null;
              }
            } else {
              header = false;
            }
          }
          MapSequence.fromMap(priceCache).put(symbol, prices);
        }
        return new Money(ListSequence.fromList(prices).getElement(0).getAdjustedClose(), "USD");
      } catch (MalformedURLException e) {
        return null;
      } catch (IOException e) {
        return null;
      }
    } else {
      return null;
    }
  }

  public static String trim_54jj5w_a0a0a0a2a0a7a1a0a0a21(String str) {
    return (str == null ? null : str.trim());
  }
}