Java 修改else if和|运算符

我有这段代码，想知道是否存在使其更具可读性的方法

我的代码：

     public String getMonthName()
{
    if (1 == this.monthNumber) {
        monthName = "January";
    } else if (2 == this.monthNumber) {
        monthName = "February";
    } else if (3 == this.monthNumber) {
        monthName = "March";
    } else if (4 == this.monthNumber) {
        monthName = "April";
    } else if (5 == this.monthNumber) {
        monthName = "May";
    } else if (6 == this.monthNumber) {
        monthName = "June";
    } else if (7 == this.monthNumber) {
        monthName = "July";
    } else if (8 == this.monthNumber) {
        monthName = "August";
    } else if (9 == this.monthNumber) {
        monthName = "September";
    } else if (10 == this.monthNumber) {
        monthName = "Oktober";
    } else if (11 == this.monthNumber) {
        monthName = "November";
    } else if (12 == this.monthNumber) {
        monthName = "December";
    }

    return monthName;
}

/**
 * Gets the number of days in this month
 * @return the number of days in this month in a non-leap year
 */
public int getNumberOfDays()
{
    int numberOfDays;
    if (monthNumber == 1 || monthNumber == 3 || monthNumber == 5 || monthNumber == 7 || monthNumber == 9 || monthNumber == 11) {
        numberOfDays = 31;
    } else if (monthNumber == 4 || monthNumber == 6 || monthNumber == 8 || monthNumber == 10 || monthNumber == 12) {
        numberOfDays = 30;
    } else {
        numberOfDays = 28;
    }

    return numberOfDays;
}
}

---

如何更好地重构代码？使其更具可读性。

制作一个存储所有名称的数组。如果this.monthNumber介于1和12之间，请从数组中读取名称。

不确定这是否正是您所要求的，但这只是一个开始！如果您希望以其他方式进行评论

public string getMonthName(int nbr){
    String[] months = {"January", "February", "Mars", "April", "May", "June", "July", "August", "September", "Oktober", "November", "December"}:    
    return months[nbr-1];
}

public int nbrOfDays(int nbr){
    int[] nbrOfDays= {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
    return nbrOfDays[nbr-1];
}

---

编辑：修复了“索引0问题”。

使用

enum

s。月份及其顺序/数量和天数不会改变，因此月份是一个很好的例子，说明何时以及如何使用月份。 让枚举有一个int

numberOfDays

，如果需要

monthNumber

。尽管您需要进入

enum

s，但您将获得很多好处，因为您可以重用您的代码，也可以省略if/switch语句。

使用enum

public String getMonthName(){
     switch (this.monthNumber) {
                case 1:  monthString = "January";
                    break;
                case 2:  monthString = "February";
                    break;
                case 3:  monthString = "March";
                    break;
                case 4:  monthString = "April";
                    break;
                case 5:  monthString = "May";
                    break;
                case 6:  monthString = "June";
                    break;
                case 7:  monthString = "July";
                    break;
                case 8:  monthString = "August";
                    break;
                case 9:  monthString = "September";
                    break;
                case 10: monthString = "October";
                    break;
                case 11: monthString = "November";
                    break;
                case 12: monthString = "December";
                    break;
                default: monthString = "Invalid month";
                    break;
      }
      return monthString;
}

public enum Month
{
  JANUARY( "January", 31 ),
  FEBRUARY( "February", 28 ),
  ...
  DECEMBER( "December", 31 );

  private String monthName;
  private int numOfDays;

  private Month ( String monthName, int numOfDays )
  {
    this.monthName = monthName;

    this.numOfDays = numOfDays;
  }

  public String getDisplayName ( )
  {
    return monthName;
  }

  public int getNumOfDays ( )
  {
    return numOfDays;
  }
}

---

您应该使用

Calendar

类，它是用来避免所有这些额外分支的。您也不必确定这是否是闰年，API将为您记录这一点

final String[] months = new String[]{ "January", "February", ... };

public String getMonthName() {
    return months[Calendar.getInstance().get(Calendar.MONTH)];
}

public int getNumberOfDays() {
    return Calendar.getInstance().getActualMaximum(Calendar.DAY_OF_MONTH);
}

---

为月份和每月的日期数制作两个

数组。两个都是12号的

在month数组中，将月份名称按索引0到11的顺序排列，并将天数按索引0到11的顺序排列。现在您可以通过索引检索数据。
为什么不直接使用
日历
和
SimpleDataFormat
？不要忘记数组索引是基于0的。世界末日是2012年，所以没有问题！！两件事：这不包括闰年，它不会编译，因为字符串周围缺少引号<代码>“一月”等…

我修正了引号。然而，我认为在这一点上，把闰年混为一谈会让人感到困惑，对莫思来说也是如此length@Hunter麦克米伦。提供的方法OP在一年内没有任何准备金。但是也可以采用这个枚举来识别闰年。我想我的主要观点是这个功能已经存在于标准SDK中了。为什么要再创造一次呢？@Hunter-McMillen。我同意您不应该重新设计日历（特别是有JodaTime），但是OP可以使用一个熟悉的示例来学习更好的编程技术。毕竟，教科书中充满了相同的内容。

public String getMonthName(){
     switch (monthNumber) {
         case 1:  return "January";
         case 2:  return "February";
         case 3:  return "March";
         case 4:  return "April";
         case 5:  return "May";
         case 6:  return "June";
         case 7:  return "July";
         case 8:  return "August";
         case 9:  return "September";
         case 10: return "October";
         case 11: return "November";
         case 12: return "December";
         default: return "Invalid month";
      }
}

public String getMonthName(){
     switch (monthNumber) {
         case 1:  return "January";
         case 2:  return "February";
         case 3:  return "March";
         case 4:  return "April";
         case 5:  return "May";
         case 6:  return "June";
         case 7:  return "July";
         case 8:  return "August";
         case 9:  return "September";
         case 10: return "October";
         case 11: return "November";
         case 12: return "December";
         default: return "Invalid month";
      }
}