Exception, Unicode and Double checking and printing Exercise

• Write a program that ask the user for the number to print as a unicode character.
• If the user enters a letter, tell the user they entered a letter instead of a number.
• Print the number as a unicode character by casting it to a char.
• Divide the number by 3. three times. Then multiply that result back by 27. Print the result with only 2 decimal places using the DecimalFormatter class
• Compare the final result to the original number to see whether they are the exact same number exactly.
• Compare the final result to the original number to see whether they are within +/- .001 of each other.

Reminders:

DecimalFormatter object knows: How to print decimals
Package to import: import java.text.DecimalFormat;
How to create a DecimalFormatter for your numbers:
DecimalFormat percentage2 = new DecimalFormat(“0.00%”);

How to use a DecimalFormatter to print to your screen:
System.out.println(percentage2.format(.308)); // will print 30.80%
Different format options:
0 = required position
# = show it if you have it
% = make it a % (mult by 100)
E = E notation (scientific)

Try/Catch:

• You can stop executing a method with a throw command.
  • Create an exception to throw – new IllegalArgumentException(“tell about the error”);
• You can catch the error in the calling program using a try /catch block.

  Try{}
  Catch{}

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  ANSWER

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import java.util.Scanner;
import java.text.DecimalFormat;
public class workwithException
{
public static void main(){
Scanner myman = new Scanner(System.in);
DecimalFormat twoplaces = new DecimalFormat("0.00");

System.out.println("Please enter a number");

try {

int x = myman.nextInt();
System.out.println("The number " + x + " in unicode represents the char "
+ (char)x);
double new1 = x/3.; // x = 5 will cause mismatch
new1 = new1/3.;
new1 = new1/3.;
new1 = new1*27;
if (new1 == x)
{

System.out.println ("It matches exactly");

}
else
{

System.out.println("No exact Match x = " + x + " and new1 = " + new1);
if (Math.abs(x-new1)< .001)

{

System.out.println ("It matches within .001");

}
else
{

System.out.println ("Still no match within .001");

}

}
System.out.println("The decimal formatted is " + twoplaces.format(new1));

}
catch (Exception e)
{
System.out.println("You did not enter an integer");
}

}
}