Missing Return Statement Error w/ For Loop - JAVA

Question

I get a missing return statement error on the last bracket and I have no idea why. This method basically takes in a string that corresponds to the students course and the current survey question they are on. The outer if statements correspond to the subject (eg: math, science, english...). The for loop iterates through an array and matches the user input ("US History") with a string in an array list. If they are equal, it returns the index at which it was found. Else, it continues the for loop. The method returns an int, but I still get an error on the last bracket. PLEASE HELP!

 public static int findNumber(String course, int currentQuestion) {
    String newCourse = course.toLowerCase();

    if (RateDriver.levelText.equals("math")) {
      for (int i = 0; i < RateSurvey.math.length-1;i++) {
        if (newCourse.equals(RateSurvey.math[i])) return survey[currentQuestion][i];
      }
      return 100;
    }

    else if (RateDriver.levelText.equals("science")) {
      for (int i = 0; i < RateSurvey.science.length-1;i++) {
        if (newCourse.equals(RateSurvey.science[i])) return survey[currentQuestion][i];

      }
      return 100;
    }
    else if (RateDriver.levelText.equals("english")) {
      for (int i = 0; i < RateSurvey.english.length-1;i++) {
        if (newCourse.equals(RateSurvey.english[i])) return survey[currentQuestion][i];

      }
      return 100;
    }
    else if (RateDriver.levelText.equals("social studies")) {
      for (int i = 0; i < RateSurvey.social.length-1;i++) {
        if (newCourse.equals(RateSurvey.social[i]))  return survey[currentQuestion][i];
      }
    }
    else if (RateDriver.levelText.equals("art")) {
      for (int i = 0; i < RateSurvey.art.length-1;i++) {
        if (newCourse.equals(RateSurvey.art[i])) return survey[currentQuestion][i];
      }
      return 100;
    }
    else if (RateDriver.levelText.equals("pe")) {
      for (int i = 0; i < RateSurvey.pe.length-1;i++) {
        if (newCourse.equals(RateSurvey.pe[i])) return survey[currentQuestion][i];
      }
    }
    else if (RateDriver.levelText.equals("chinese")) {
      for (int i = 0; i < RateSurvey.chinese.length-1;i++) {
        if (newCourse.equals(RateSurvey.chinese[i])) return survey[currentQuestion][i];
      }
    }
    else if (RateDriver.levelText.equals("japanese")) {
      for (int i = 0; i < RateSurvey.japanese.length-1;i++) {
        if (newCourse.equals(RateSurvey.japanese[i])) return survey[currentQuestion][i];
      }
      return 100;
    }
    else if (RateDriver.levelText.equals("french")) {
      for (int i = 0; i < RateSurvey.french.length-1;i++) {
        if (newCourse.equals(RateSurvey.french[i])) return survey[currentQuestion][i];
      }
      return 100;
    }
    else if (RateDriver.levelText.equals("spanish")) {
      for (int i = 0; i < RateSurvey.spanish.length-1;i++) {
        if (newCourse.equals(RateSurvey.spanish[i])) return survey[currentQuestion][i];
      }
      return 100;
    }
    else if (RateDriver.levelText.equals("hawaiian")) {
      for (int i = 0; i < RateSurvey.hawaiian.length-1;i++) {
        if (newCourse.equals(RateSurvey.hawaiian[i])) return survey[currentQuestion][i];
      }
      return 100;
    }
    else return 100;

  **}** // this is where I get the error

Answer 1

Some of the parts of your code don't return anything if nothing is returned in the for loop, such as this one:

else if (RateDriver.levelText.equals("social studies")) {
  for (int i = 0; i < RateSurvey.social.length-1;i++) {
    if (newCourse.equals(RateSurvey.social[i]))  return survey[currentQuestion][i];
  }
}

So if the program reaches this part of the code and doesn't end up returning survey[currentQuestion][i] , then it will skip to the end of the if-else chain and not return anything. You should change them to something like this:

else if (RateDriver.levelText.equals("social studies")) {
  for (int i = 0; i < RateSurvey.social.length-1;i++) {
    if (newCourse.equals(RateSurvey.social[i]))  return survey[currentQuestion][i];
  }
  return 100;
}

Answer 2

Just remove the else before the last return 100; That means it will happen for every case that isn't handle by the huge if statement. It may be the same thing, but it just makes the code clearer.

Answer 3

You need to add an additional bracket after the one that is getting you an error.

The following doesn't get any compiling errors:

public static int findNumber(String course, int currentQuestion) {
            String newCourse = course.toLowerCase();

            if (RateDriver.levelText.equals("math")) {
              for (int i = 0; i < RateSurvey.math.length-1;i++) {
                if (newCourse.equals(RateSurvey.math[i])) return survey[currentQuestion][i];
              }
              return 100;
            }

            else if (RateDriver.levelText.equals("science")) {
              for (int i = 0; i < RateSurvey.science.length-1;i++) {
                if (newCourse.equals(RateSurvey.science[i])) return survey[currentQuestion][i];

              }
              return 100;
            }
            else if (RateDriver.levelText.equals("english")) {
              for (int i = 0; i < RateSurvey.english.length-1;i++) {
                if (newCourse.equals(RateSurvey.english[i])) return survey[currentQuestion][i];

              }
              return 100;
            }
            else if (RateDriver.levelText.equals("social studies")) {
              for (int i = 0; i < RateSurvey.social.length-1;i++) {
                if (newCourse.equals(RateSurvey.social[i]))  return survey[currentQuestion][i];
              }
            }
            else if (RateDriver.levelText.equals("art")) {
              for (int i = 0; i < RateSurvey.art.length-1;i++) {
                if (newCourse.equals(RateSurvey.art[i])) return survey[currentQuestion][i];
              }
              return 100;
            }
            else if (RateDriver.levelText.equals("pe")) {
              for (int i = 0; i < RateSurvey.pe.length-1;i++) {
                if (newCourse.equals(RateSurvey.pe[i])) return survey[currentQuestion][i];
              }
            }
            else if (RateDriver.levelText.equals("chinese")) {
              for (int i = 0; i < RateSurvey.chinese.length-1;i++) {
                if (newCourse.equals(RateSurvey.chinese[i])) return survey[currentQuestion][i];
              }
            }
            else if (RateDriver.levelText.equals("japanese")) {
              for (int i = 0; i < RateSurvey.japanese.length-1;i++) {
                if (newCourse.equals(RateSurvey.japanese[i])) return survey[currentQuestion][i];
              }
              return 100;
            }
            else if (RateDriver.levelText.equals("french")) {
              for (int i = 0; i < RateSurvey.french.length-1;i++) {
                if (newCourse.equals(RateSurvey.french[i])) return survey[currentQuestion][i];
              }
              return 100;
            }
            else if (RateDriver.levelText.equals("spanish")) {
              for (int i = 0; i < RateSurvey.spanish.length-1;i++) {
                if (newCourse.equals(RateSurvey.spanish[i])) return survey[currentQuestion][i];
              }
              return 100;
            }
            else if (RateDriver.levelText.equals("hawaiian")) {
              for (int i = 0; i < RateSurvey.hawaiian.length-1;i++) {
                if (newCourse.equals(RateSurvey.hawaiian[i])) return survey[currentQuestion][i];
              }
              return 100;
            }
            else return 100;

          }
        } //ADDED