exchangerate.java

来自「JAVA Servlet2.3外文书籍源码」· Java 代码 · 共 37 行

import java.util.Hashtable;

public class ExchangeRate {

  private Hashtable rate_table;

  public ExchangeRate() {
    rate_table = new Hashtable(6);
    rate_table.put( "CA", new Double(  1.562600)); //Canada
    rate_table.put( "EU", new Double(  1.090394)); //Euro
    rate_table.put( "JP", new Double(120.435000)); //Japan
    rate_table.put( "MX", new Double(  9.589000)); //Mexico
    rate_table.put( "UK", new Double(  0.676133)); //United Kingdom
    rate_table.put( "US", new Double(  1.000000)); //United States
  }
  
  public double getExchangeRate(String country_code) {
    Object obj = rate_table.get(country_code);
    double rval = 0;
    if (obj != null) {
      rval = ((Double)obj).doubleValue();
    }
    return rval;
  }

  public double getExchangeRate(String country1, String country2){
    double rval;
    double currency1_per_usdollar = getExchangeRate( country1 );
    double currency2_per_usdollar = getExchangeRate( country2 );

    if( currency2_per_usdollar > 0.0 )
      rval = currency1_per_usdollar/currency2_per_usdollar;
    else
      rval = 0.0;
    return rval;
  }
}