java - 创建一个 Util 类

Question

我创建了一个货币格式器类。我希望这是一个 util 类，可以被其他应用程序使用。现在我只使用一个字符串，而不是希望它由导入我的 currencyUtil.jar

的应用程序设置

public class CurrencyUtil{
  public BigDecimal currencyUtil(RenderRequest renderRequest, RenderResponse renderResponse)
        throws IOException, PortletException {
        BigDecimal amount = new BigDecimal("123456789.99");  //Instead I want the amount to be set by the application.      
        ThemeDisplay themeDisplay = 
             (ThemeDisplay)renderRequest.getAttribute(WebKeys.THEME_DISPLAY);
        Locale locale = themeDisplay.getLocale();

        NumberFormat canadaFrench = NumberFormat.getCurrencyInstance(Locale.CANADA_FRENCH);
        NumberFormat canadaEnglish = NumberFormat.getCurrencyInstance(Locale.CANADA);
        BigDecimal amount = new BigDecimal("123456789.99");
        DecimalFormatSymbols symbols = ((DecimalFormat) canadaFrench).getDecimalFormatSymbols();
        symbols.setGroupingSeparator('.');
        ((DecimalFormat) canadaFrench).setDecimalFormatSymbols(symbols);

    System.out.println(canadaFrench.format(amount));
        System.out.println(canadaEnglish.format(amount));     
    //Need to have a return type which would return the formats
     return amount;
    }
}

让调用这个util类的其他应用程序成为

 import com.mypackage.CurrencyUtil;
 ...
 public int handleCurrency(RenderRequest request, RenderResponse response) {
String billAmount = "123456.99";
    CurrencyUtil CU = new currencyUtil();
//Need to call that util class and set this billAmount to BigDecimal amount in util class.
//Then it should return both the formats or the format I call in the application.
   System.out.println(canadaEnglish.format(billAmount);  //something like this
}

我做了什么改变？

Answer 1

您需要创建一个 CurrencyUtil 类的对象。

CurrencyUtil CU = new CurrencyUtil();
//To call a method,
BigDecimal value=CU.currencyUtil(request,response);

我建议 currenyUtil 方法应该是 static 并且它需要三个参数。

public class CurrencyUtil
 {
  public static BigDecimal currencyUtil(
                RenderRequest renderRequest, 
                RenderResponse renderResponse,
                String amountStr) throws IOException, PortletException 
    {
       BigDecimal amount = new BigDecimal(amountStr); 
       ...
    }
 }

你可以这样调用它，

 BigDecimal value=CurrencyUtil.currencyUtil(request,response,billAmount);