带有try / catch异常的Java问题

Question

This is my first time using the site so forgive me if I don't have things formatted correctly. But I'm pretty much a beginner with Java and am trying to create this program for a computer science course online and I need to use doubles in a Try/Catch in Java and I'm not sure how to go about doing it.

I know I need to use Math.pow() somewhere, but the instructor didn't exactly make it clear how to do this and I'm unable to contact them.

Here's the error code I'm getting and maybe that will better explain what I'm trying to do:

CollectInfo.java:22: error: method collectWage in class Validate cannot be applied to given types;
double wage = Validate.collectWage("Please enter your hourly wage");
^
required: double
found: String
reason: actual argument String cannot be converted to double by method invocation conversion
1 error 

Here is an example of the code I have that is working so far, but I don't know how to fix to correct the error.

import java.util.*;
import java.util.regex.*;

public class CollectInfo {

public static void main(String[] args) {
    int id = Validate.collectInt("Please enter the ID of the Item");
    String fname = Validate.collectString(3, "Please enter the first name");
    String lname = Validate.collectString(5, "Please enter the last name");
    String email = Validate.collectEmail("Please enter your email address");
    String phone = Validate.collectPhone("Please enter your phone Number\n"
            + "Like (123) 456-7890 or 1234567890 or 123-456-7890");
    String zipcode = Validate.collectZip("Please enter the zipcode");
    String ssn = Validate.collectSsn("Please enter your SSN");
    double wage = Validate.collectWage("Please enter your hourly wage");


    System.out.print(String.format("id: %s\nName: %s %s\nEmail: %s\n"
            + "Phone: %s\nZipCode: %s\n SSN: %s\nWage:%s\n\n",
            id,fname,lname,email,phone,zipcode,ssn,wage));
} //  end main method
}  //end class CollectInfo

class Validate {

public static int collectInt(String messageIn) {
    Scanner input = new Scanner(System.in);
    int intOut = 0;
    boolean valid = true;

    System.out.println(messageIn);
    while (valid) {
        try {
            intOut = input.nextInt();
            valid = false;
        } catch (InputMismatchException e) {
            input.nextLine();
            System.out.println("You must enter a whole number!");
        } // end catch

    }   // end while
    return intOut;


} // end collectInt

public static String collectString(int strLen, String messageIn) {
    Scanner input = new Scanner(System.in);
    String outStr = "";
    boolean valid = true;
    System.out.println(messageIn);
    while (valid) {
        try {
            outStr = input.nextLine();
            if (outStr.length() < strLen) {
                throw new Exception();
            }
            valid = false;
        } catch (Exception e) {
            System.out.printf("You must have more than %s characters\n", strLen);
        } // end catch
    }// end while
    return outStr;
}

public static String collectZip(String messageIn) {
    Scanner input = new Scanner(System.in);
    String outStr = "";
    boolean valid = true;
    System.out.println(messageIn);
    while (valid) {
        try {
            outStr = input.nextLine();
            Integer.parseInt(outStr);
            if (outStr.length() != 5) {
                throw new Exception();
            }
            valid = false;
        } catch (NumberFormatException ne) {
            System.out.printf("Please enter a valid zip code\n");
        } catch (Exception e) {
            System.out.println("A zip code must be 5 characters long");
        }
    }// end while
    return outStr;
}

public static String collectEmail(String messageIn) {
    String expression = "^[\\w\\-]([\\.\\w])+[\\w]+@([\\w\\-]+\\.)+[A-Z]{2,4}$";
    Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);

    Scanner input = new Scanner(System.in);
    String outStr = "";
    boolean valid = true;
    System.out.println(messageIn);
    while (valid) {
        try {
            outStr = input.nextLine();
            CharSequence emailChk = outStr;
            Matcher matcher = pattern.matcher(emailChk);
            if (!matcher.matches()) {
                throw new Exception();
            }
            valid = false;
        } catch (Exception e) {
            System.out.printf("Please enter a valid email address\n");
        } // end catch
    }// end while
    return outStr;
}

//***************************************************************************

public static Double collectWage(String messageIn) {
Scanner input = new Scanner(System.in);
String strOut = "";
boolean valid = true;
double out = 0;

System.out.println(messageIn);
while (valid) {
    try {
        strOut = input.nextLine();
        if (strOut.length() != 4) {
            throw new Exception();
        }
        out = Double.parseDouble(strOut);
        valid = false;
    } catch (NumberFormatException ne) {
        System.out.println("Please enter a valid wage");
    } catch (Exception e) {

        System.out.printf("A wage should be 4 numbers long");
    } //end catch
} //end while

return out;


}//end collectWage method

//***************************************************************************

public static String collectPhone(String messageIn) {
    String expression = "^\\(?(\\d{3})\\)?[- ]?(\\d{3})[- ]?(\\d{4})$";
    Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);

    Scanner input = new Scanner(System.in);
    String strOut = "";
    boolean valid = true;

    System.out.println(messageIn);
    while (valid) {
        try {
            strOut = input.nextLine();
            CharSequence phoneChk = strOut;
            Matcher matcher = pattern.matcher(phoneChk);
            if (!matcher.matches()) {
                throw new Exception();
            }
            valid = false;
        } catch (Exception e) {
            System.out.printf("Please try again with a valid phone "
                    + "number\n");
        } //end catch
    } //end while

    return strOut;

}//end collectPhone method


//***************************************************************************
public static String collectSsn(String messageIn) {
    String expression = "^\\d{3}[- ]?\\d{2}[- ]?\\d{4}$";
    Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);

    Scanner input = new Scanner(System.in);
    String strOut = "";
    boolean valid = true;

    System.out.println(messageIn);
    while (valid) {
        try {
            strOut = input.nextLine();
            CharSequence ssnChk = strOut;
            Matcher matcher = pattern.matcher(ssnChk);
            if (!matcher.matches()) {
                throw new Exception();
            }
            valid = false;
        } catch (Exception e) {
            System.out.printf("Please try again with a valid social security "
                    + "number\n");
        } //end catch
    } //end while

    return strOut;

}//end collectSsn method


}  // end of class Validate

I know that I don't need the 3 number length or anything like that, but this is just an example of what I did get working.

I'd appreciate any help you guys could provide in helping me figure things out.

Answer 1

try this

public static void main(String[] args) {
    double wage = Validate.collectWage("Please enter your hourly wage");

}// end main method

public static Double collectWage(String messageIn) {
    Scanner input = new Scanner(System.in);
    String strOut = "";
    boolean valid = true;
    double out = 0;

    System.out.println(messageIn);
    while (valid) {
        try {
            strOut = input.nextLine();
            if (strOut.length() != 3) {
                throw new Exception();
            }
            out = Double.parseDouble(strOut);
            valid = false;
        } catch (NumberFormatException ne) {
            System.out.println("Please enter a valid wage");
        } catch (Exception e) {

            System.out.printf("A wage should be 3 numbers long");
        } //end catch
    } //end while

    return out;


}//end collectWage method