变量“result”可能尚未初始化

Question

public class MonthName {
  public static String month_name(int month) {
    String result;

    if (month == 1) {
      result = "January";
    } else if (month == 2) {
      result = "February";
    } else if (month == 3) {
      result = "February";
    } else if (month == 4) {
      result = "February";
    } else if (month == 5) {
      result = "February";
    } else if (month == 6) {
      result = "February";
    } else if (month == 7) {
      result = "February";
    } else if (month == 8) {
      result = "February";
    } else if (month == 9) {
      result = "February";
    } else if (month == 10) {
      result = "February";
    } else if (month == 11) {
      result = "February";
    } else if (month == 12) {
      result = "February";
    }

    return result;
  }


  public static void main(String[] args) {
    System.out.println("Month 1: " + month_name(1));
    System.out.println("Month 2: " + month_name(2));
    System.out.println("Month 3: " + month_name(3));
    System.out.println("Month 4: " + month_name(4));
    System.out.println("Month 5: " + month_name(5));
    System.out.println("Month 6: " + month_name(6));
    System.out.println("Month 7: " + month_name(7));
    System.out.println("Month 8: " + month_name(8));
    System.out.println("Month 9: " + month_name(9));
    System.out.println("Month 10: " + month_name(10));
    System.out.println("Month 11: " + month_name(11));
    System.out.println("Month 12: " + month_name(12));
    System.out.println("Month 43: " + month_name(43));
  }
}

所以我已经在结果中声明了相关字符串的值，但是它仍然说我的变量“result”可能还没有初始化。

我正在尝试实现与此类似的输出。任何人都可以帮我吗？谢谢！

Answer 1

由于月只是一个int，它可以采用1-12以外的值（您的if/其他/if结构处理）。

要消除错误，您可以将其初始化为空字符串，但是，您可能需要考虑错误情况。

例如，如果传递的内容不在1-12范围内，该方法应该做什么？

Answer 2

局部变量应该在使用前初始化。它们没有默认值

初始化它

String result="";

Answer 3

如果你的可变月份可能是空的或是别的什么，这可能会发生

js lang-js prettyprint-override">public class MonthName {
  public static String month_name(int month) {
    String result = "";

    if (month == 1) {
      result = "January";
    } else if (month == 2) {
      result = "February";
    } else if (month == 3) {
      result = "February";
    } else if (month == 4) {
      result = "February";
    } else if (month == 5) {
      result = "February";
    } else if (month == 6) {
      result = "February";
    } else if (month == 7) {
      result = "February";
    } else if (month == 8) {
      result = "February";
    } else if (month == 9) {
      result = "February";
    } else if (month == 10) {
      result = "February";
    } else if (month == 11) {
      result = "February";
    } else {
      result = "February";
    }

    return result;
  }


  public static void main(String[] args) {
    System.out.println("Month 1: " + month_name(1));
    System.out.println("Month 2: " + month_name(2));
    System.out.println("Month 3: " + month_name(3));
    System.out.println("Month 4: " + month_name(4));
    System.out.println("Month 5: " + month_name(5));
    System.out.println("Month 6: " + month_name(6));
    System.out.println("Month 7: " + month_name(7));
    System.out.println("Month 8: " + month_name(8));
    System.out.println("Month 9: " + month_name(9));
    System.out.println("Month 10: " + month_name(10));
    System.out.println("Month 11: " + month_name(11));
    System.out.println("Month 12: " + month_name(12));
    System.out.println("Month 43: " + month_name(43));
  }
}