在方法的参数中使用OR

Question

How can I include multiple terms as a single arguments to a method?

For example: method is declared as follows:

 public void showSchedules(String day, String AMPM);

I want to call something like

showSchedules ("Monday" || "Tuesday", AM);

but the operators cannot be applied to java lang String. Any tips?

Answer 1

What you are suggesting is not possible. The || operator in Java is a logical (boolean) operator. It evaluates the boolean expressions on either side (if necessary) and returns a boolean value. So your suggestion will never work since the expressions on each side are Strings and not booleans.

You have three options here:

1. Pass each argument individually into the method, or if you don't know how many there will be pass them in an array or some other collection.

showSchedules("Monday", "Tuesday", AM) {...}

or

showSchedules(new String[] {"Monday", "Tuesday"}, AM) {...}

2. Call the method twice, passing in one argument each time and then deal with the results in the calling method.

3. Invert the order of params and use varargs :

showSchedules(String AmPm, String... days) {...}

Answer 2

No. You cannot do that in passing arguments. However you can only control the functionality.

For ex

public void showSchedules(String day, String AMPM) {
    if (day.equals("Monday") ||  day.equals("Tuesday") ) {
       //TODO
    }

  }

Answer 3

You can totally do that with an varargs, like so:

day will be an array of strings and you can pass as many as you want

public void showSchedules(String AMPM, String... day) {
    // you'll have to iterate through them here
    for(String d:day)
{
  switch(d)
    {
        case "Monday":
        break;
        case "Tuesday":
        break;
    }
}

}