Java Please help I was wondering how I can get the code to n

Java Please help!

I was wondering how I can get the code to not repeat when the user puts something in other than m or f.

System.out.println(\"Are you Female or Male (F for female and M for male)\");   
String inputString = keyboard.next();
inputString = inputString.toUpperCase();
char gender = inputString.charAt(0);
  
//If Gender does not equal M and F it gets error
//Otherwise, if it does, it is set in object
//Increments info_counter
while(gender != \'M\' || gender != \'F\')
{
System.out.println(\"Please pick F or M\");
System.out.println(\"Are you Female or Male (F for female and M for male)\");
inputString = inputString.toUpperCase();
gender = inputString.charAt(0);
}   
user.setUserGender(gender);

Second questions is how could I convert this code into a while so that repeat if the user puts the wrong information in

  
System.out.println(\"How fast were you going? (MPH)\");
int speed = keyboard.nextInt();
if(speed <= 0 || speed > 30)
{
System.out.println(\"Remember how fast you were going... not your car\");
}
else
{
user.setUserActivitySpeed(speed);
}
  
  

Solution

public static void main(String[] args) {

        //declare the variables

        String gender;                              //the gender of the user

        Scanner scanner = new Scanner(System.in);       //text input scanner

System.out.println(\"\ Are you male or female? (format: M or F)\");

        gender = scanner.next();

        System.out.println(gender); //an output line for debugging

        if (gender == \"M\") gender = \"Male\";

        else gender = \"Female\";

        System.out.println(\"\ You said you are:\");

        System.out.println(gender);

import java.util.Scanner;

public class Distance{

public static void main(String [] args){

Scanner keyboard = new Scanner(System.in);

int time , speed , hour;

double distance;

System.out.println(\"How fast were you going ?\");

speed = keyboard.nextInt();

while(speed<=0)

{

     System.out.println(\"Please enter a valid speed \");

     speed = keyboard.nextInt();

}

System.out.println(\" How long did you ride / drive ?\");

time = keyboard.nextInt();

while(time<=0)

{

     System.out.println(\"Please enter a valid time \");

     time = keyboard.nextInt();

}

System.out.println(\" Hour                         Distance\");

System.out.println(\"---------------------------------\");

hour = 0;

for( int x = 1; x<=time; x++)

{

     hour++;

     if(hour>1)

     {

        distance = time * speed;

        System.out.println(time+ \"                \" +distance);

     }

    }

   }

}