Question

In Java form

1. Declare and assign a char variable called myLetter to z.
2. Write a Java statement that makes myLetter uppercase.
3. Write a java statement that finds out if myLetter is a digit.
4. Write a java statement that finds out if myLetter is an upper case letter.
5. Assume myLetter = ‘Z’;
   What is the output for System.out.print(myLetter++);
6. Assume myLetter = ‘Z’;
   What is the output for System.out.print(++myLetter);
7. Assume myLetter = ‘Z’;
   What is the output for System.out.print(myLetter--);
8. What happens when a floating-point data type, like double, is cast into a char? (page 127)
9. Evaluate the following Java statement: char c = 90;
10. What Java method in the Character class lets me know if my character is a letter?

Answer 1

Answers:

//  Declare and assign a char variable called myLetter to z.
         char myLetter = 'z';
         
        //  Write a Java statement that makes myLetter uppercase
         myLetter -= 32; 
        System.out.println(myLetter);
        
        // Write a java statement that finds out if myLetter is a digit
        boolean flag = Character.isDigit(myLetter);
        System.out.println(myLetter + " is Character: " + flag);
        
        // Write a java statement that finds out if myLetter is an upper case letter.
        flag =Character.isUpperCase(myLetter);
        System.out.println(myLetter + " is uppercase letter: " + flag);
        
        //Assume myLetter = ‘Z’;
        // What is the output for System.out.print(myLetter++);
        //ans: Z.
        myLetter = 'Z';
        System.out.println(myLetter++);
        // Assume myLetter = ‘Z’;
        // What is the output for System.out.print(++myLetter);
        // ans: [
        myLetter = 'Z';
        System.out.println(++myLetter);
        
        // Assume myLetter = ‘Z’;
        // What is the output for System.out.print(myLetter--);
        // ans: Z
        myLetter = 'Z';
        System.out.println(myLetter--);
        
        // What happens when a floating-point data type, like double, is cast into a char?
        //ans: it narrow down the float to its integer part
        myLetter = (char)66.37;   //equal to myLetter = 66;
        System.out.println(myLetter);
        
        // Evaluate the following Java statement: char c = 90;
        char c=90;
        // What Java method in the Character class lets me know if my character is a letter?
        System.out.println(Character.isLetter(c));

Java code: Main.java

public class Main{
        
     public static void main(String []args){
        //  Declare and assign a char variable called myLetter to z.
         char myLetter = 'z';
         
        //  Write a Java statement that makes myLetter uppercase
         myLetter -= 32; 
        System.out.println(myLetter);
        
        // Write a java statement that finds out if myLetter is a digit
        boolean flag = Character.isDigit(myLetter);
        System.out.println(myLetter + " is Character: " + flag);
        
        // Write a java statement that finds out if myLetter is an upper case letter.
        flag =Character.isUpperCase(myLetter);
        System.out.println(myLetter + " is uppercase letter: " + flag);
        
        //Assume myLetter = ‘Z’;
        // What is the output for System.out.print(myLetter++);
        //ans: Z.
        myLetter = 'Z';
        System.out.println(myLetter++);
        // Assume myLetter = ‘Z’;
        // What is the output for System.out.print(++myLetter);
        // ans: [
        myLetter = 'Z';
        System.out.println(++myLetter);
        
        // Assume myLetter = ‘Z’;
        // What is the output for System.out.print(myLetter--);
        // ans: Z
        myLetter = 'Z';
        System.out.println(myLetter--);
        
        // What happens when a floating-point data type, like double, is cast into a char?
        //ans: it narrow down the float to its integer part
        myLetter = (char)66.37;   //equal to myLetter = 66;
        System.out.println(myLetter);
        
        // Evaluate the following Java statement: char c = 90;
        char c=90;
        // What Java method in the Character class lets me know if my character is a letter?
        System.out.println(Character.isLetter(c));
     }
}

Output: