Question

I’m working on a method that takes a string time, which contains 3 to 4 numbers representing military time, such as “130” or “1245”. The purpose of this method is to assign the contents of the string time to an integer array with two parts: [0] is the hour (such as “1” or “12” from my example above), and [1] represents the minutes (“30” or “45” from my example).

The if(str.length() ==3) is meant to catch strings such as “130”, where the hour is less than 10 and the string lacks a leading zero.

When I compile, the errors I get read:

error: incompatible types
                          temp = a[1] + a[2];
                                      ^
required: String
found: int

.

error: incompatible types
                          temp = a[0] + a[1];
                                      ^
required: String
found: int

.

error: incompatible types
                          temp = a[2] + a[3];
                                      ^
required: String
found: int

.

I’ve been reading up on the char data type, and from what I understand it has a numerical value similar to an integer. I’ve attempted to typecast with:

temp = (String) a[1] + a[2];

But that gives the following error:

error: inconvertible types
                          temp = (String) a[1] + a[2];
                                           ^
required: String
found: char

At this point I’m not sure what to do. Below is my code:

private int[] convertStringToHoursMins(String time) {
    String str = time;
    String temp;
    char[] a = str.toCharArray();
    int[] hoursMins = new int[2];
    try {
        if (str.length() == 3) {
            hoursMins[0] = a[0];
            temp = a[1] + a[2];
            hoursMins[1] = Integer.parseInt(temp);
        }
        else {
            temp = a[0] + a[1];
            hoursMins[0] = Integer.parseInt(temp);
            temp = a[2] + a[3];
            hoursMins[1] = Integer.parseInt(temp);
        }   
    }
    catch(NumberFormatException e) {
        System.out.println("Invalid time.");
    }
    return hoursMins;
}

Thanks in advance for any help you can offer.

Answer 1

I believe you should be able to simply do this:

temp = "" + a[1] + a[2];

If you add the “”, it will convert that into a String, so you will not get the mismatch error.