fieldhelper.java

我在加拿大学习的一个比较复杂的在线银行程序.

package com.ebusiness.ebank.util;


/**
 * <p>Title: </p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2005</p>
 * <p>Company: eBusiness Inc., All right reserved</p>
 * @author unascribed
 * @version 1.0
 */

import java.sql.Timestamp;
import java.util.Locale;
import java.util.Date ;
import java.util.Calendar ;
import java.util.Set;
import java.util.ArrayList;
import java.util.Iterator;
import java.text.SimpleDateFormat;
import java.text.DateFormatSymbols;
import java.text.ParseException ;
import com.ebusiness.ebank.exception.BusinessException;
import com.ebusiness.ebank.exception.ErrorMessages;


public class FieldHelper {


  public static boolean isEmpty(String fieldValue){
      if (fieldValue == null || fieldValue.trim().length() == 0)
          return true;
      else
          return false;
  }

  //Return a new value left padded with c
  public static String leftPad(String fieldValue, int length, char c)
  {
      String newValue = "";
      int curLength;
      if (fieldValue == null || fieldValue.trim().length() == 0)
          curLength = 0;
      else
      {
          newValue = fieldValue.trim();
          curLength = newValue.length();
      }
      for (int i = 0; i < length - curLength; i++)
          newValue = c + newValue;
      return newValue;
  }

  /**
   * convert string to date as per format in userLocale
   */
  public static Timestamp convertToTimestamp(String dateValue, Locale userLocale) {

    Timestamp retTimestamp = null;
    SimpleDateFormat formatter = null;
    if (isEmpty(dateValue))
       return null;
    if (userLocale.equals(Locale.ENGLISH)) {
      formatter = new SimpleDateFormat("dd-MMM-yyyy", Locale.ENGLISH);
    } else {
      DateFormatSymbols dateSymbols = new DateFormatSymbols(Locale.FRENCH) ;
      dateSymbols.setShortMonths(Constants.newFrenchShortMonths);
      formatter =  new SimpleDateFormat("dd-MMM-yy", dateSymbols) ;
    }


    try {
       Date returnDate = formatter.parse(dateValue);
       retTimestamp = new Timestamp(returnDate.getTime());
    } catch (ParseException e){
      /**
       * do nothing, because before this method is called, "isValidDate" must be called to
       * ensure the "dateValue" is valid
       */
    }

    return retTimestamp ;


  }

  /**
   * convert string to date as per format dd-MMM-yyyy in English
   */
  public static Timestamp convertToTimestamp(String dateValue) {

    Timestamp retTimestamp = null;
    SimpleDateFormat formatter = null;
    formatter = new SimpleDateFormat("dd-MMM-yyyy");
    if (isEmpty(dateValue))
       return null;
    try {
       Date returnDate = formatter.parse(dateValue);
       retTimestamp = new Timestamp(returnDate.getTime());
    } catch (ParseException e){}

    return retTimestamp ;
  }

/**
  * Convert date to a string with format mask as dd-MMM-yyyy
  *
  */
  public static String convertToString(Date dateValue, Locale userLocale)   {

    String retValue = "" ;

    if (dateValue != null) {
      SimpleDateFormat formatter ;
      if (userLocale.equals(Locale.ENGLISH)) {
        formatter =  new SimpleDateFormat("dd-MMM-yyyy" , Locale.ENGLISH);
      } else {
        DateFormatSymbols dateSymbols = new DateFormatSymbols(Locale.FRENCH) ;
        dateSymbols.setShortMonths(Constants.newFrenchShortMonths);
        formatter =  new SimpleDateFormat("dd-MMM-yy", dateSymbols) ;
      }

      Date tempDate = new Date(dateValue.getTime()) ;
      retValue = formatter.format(tempDate);

    }

    return  retValue;
  }

/**
  * Convert date to a string with format mask as dd-MMM-yyyy in English
  */
  public static String convertToString(Date dateValue, String formatMask)   {

    String retValue = "" ;

    if (dateValue != null) {

      SimpleDateFormat formatter =  new SimpleDateFormat("dd-MMM-yyyy");

      if (formatMask != null)
        formatter = new SimpleDateFormat(formatMask) ;

      Date tempDate = new Date(dateValue.getTime()) ;
      retValue = formatter.format(tempDate);

    }

    return  retValue;
  }

  // get the next day
   public static String getNextDate(String curValue)  {

    if (isEmpty(curValue)) return null ;

    String retValue ;
    Date curDate = convertToTimestamp(curValue) ;
    Calendar calendar = Calendar.getInstance() ;
    calendar.setTime(curDate);
    calendar.add(Calendar.DATE, 1 );
    Date nextDate = calendar.getTime() ;
    Timestamp retTimestamp = new Timestamp(nextDate.getTime());
    retValue =convertToString(retTimestamp, Locale.ENGLISH) ;

    return retValue ;

  }

  // get the next day
   public static String getNextDate(String curValue, Locale userLocale)  {

    String retValue ;

    if (FieldHelper.isEmpty(curValue)) return "" ;

    Date curDate = convertToTimestamp(curValue, userLocale ) ;
    Calendar calendar = Calendar.getInstance() ;
    calendar.setTime(curDate);
    calendar.add(Calendar.DATE, 1 );
    Date nextDate = calendar.getTime() ;
    Timestamp retTimestamp = new Timestamp(nextDate.getTime());
    retValue =convertToString(retTimestamp, userLocale) ;

    return retValue ;

  }
  public static String isChecked(String value)  {
    String returnValue = " " ;

    if ("Y".equalsIgnoreCase(value.trim()))
        returnValue = "checked" ;

    return returnValue ;
  }



  public static boolean isValidPostalCode(String mpcode){

    if( mpcode.length()==6 ) {
      if (!Character.isLetter(mpcode.charAt(0))) return false;
      if (!Character.isDigit(mpcode.charAt(1))) return false;
      if (!Character.isLetter(mpcode.charAt(2))) return false;
      if (!Character.isDigit(mpcode.charAt(3)))  return false;
      if (!Character.isLetter(mpcode.charAt(4))) return false;
      if (!Character.isDigit(mpcode.charAt(5)))  return false;
      return true;
    }
    return false;

  }

  public static boolean isValidZipCode(String mpcode){

    boolean flag=true;

    try {
        if( mpcode.length()==5 )
          flag = isNumeric(mpcode) ;
        else  throw new Exception();

    } catch(Exception e) {
      flag = false;
    }

    return flag;

  }

  public static boolean isNumeric(String value){

    boolean flag=true;

    try {
        for (int i =0 ; i < value.length(); i++)
          if( !Character.isDigit(value.charAt(i))) throw new Exception();
    } catch (Exception e) {
          flag = false;
    }

    return flag ;
  }

  public static boolean isAlphanumeric(String value){

    boolean flag=true;

    try {
        for (int i =0 ; i < value.length(); i++) {
          if( !Character.isDigit(value.charAt(i)) &&  !Character.isLetter(value.charAt(i)) )
            throw new Exception();
        }
    } catch (Exception e) {
          flag = false;
    }

    return flag ;
  }

  public static boolean isEvenNumber(String value) {
    boolean flag = false ;
    try {
      long m = Long.parseLong(value)  ;
      if ((m%2) == 0)
        flag = true ;
    } catch (Exception e) {
          flag = false;
    }

    return flag ;
  }

  public static boolean isInRange(long valueFrom, long valueTo, long value) {

    if ( value<=valueTo && value>=valueFrom)
      return true ;
    else
      return false ;
  }


  /**
   * check date
   * return 0 : valid value
   * return 1 : format is wrong
   * return 2 : format is OK but value is not valid, eg. 40-Jan-2001
   */
  public static int isValidDate(String inputDate) {

    int retValue = 0 ;
    SimpleDateFormat formatter=null;
    formatter = new SimpleDateFormat("dd-MMM-yyyy");

    try {
       Date returnDate = formatter.parse(inputDate);
       if ( formatter.format(returnDate).equalsIgnoreCase(inputDate) == false) {
         retValue = 2 ;
       }

    } catch (ParseException e){
         retValue = 1 ;
    }

    return retValue ;

  }

  public static String getCurrentDate() {
    Timestamp curDate = new Timestamp(System.currentTimeMillis());
    return (FieldHelper.convertToString(curDate, Locale.ENGLISH)) ;
  }

  public static String getCurrentDate(Locale userLocale) {
    Timestamp curDate = new Timestamp(System.currentTimeMillis());
    return (FieldHelper.convertToString(curDate, userLocale)) ;
  }

}