Prentice.Hall.Introduction.to.Java.Programming,.Brief.Version.9th.(2014).[sharethefiles.com]

192 Chapter 5 Methods
For example, the decimal number 123 is 7B in hexadecimal. The conversion is done as
follows. Divide 123 by 16. The remainder is 11 (B in hexadecimal) and the quotient is 7.
Continue to divide 7 by 16. The remainder is 7 and the quotient is 0. Therefore 7B is the hexadecimal
number for 123.
0
16 7
0
7
7
16 123
112
11
Quotient
Remainder
h 1
h 0
Listing 5.8 gives a program that prompts the user to enter a decimal number and converts
it into a hex number as a string.
input decimal
decimal to hex
get a hex char
get a letter
LISTING 5.8
Decimal2HexConversion.java
1 import java.util.Scanner;
2
3 public class Decimal2HexConversion {
4 /** Main method */
5 public static void main(String[] args) {
6 // Create a Scanner
7 Scanner input = new Scanner(System.in);
8
9 // Prompt the user to enter a decimal integer
10 System.out.print("Enter a decimal number: ");
11 int decimal = input.nextInt();
12
13 System.out.println("The hex number for decimal " +
14 decimal + " is " + decimalToHex(decimal));
15 }
16
17 /** Convert a decimal to a hex as a string */
18
19
public static String decimalToHex(int decimal) {
String hex = "";
20
21 while (decimal != 0) {
22 int hexValue = decimal % 16;
23 hex = toHexChar(hexValue) + hex;
24 decimal = decimal / 16;
25 }
26
27 return hex;
28 }
29
30 /** Convert an integer to a single hex digit in a character */
31
32
public static char toHexChar(int hexValue) {
if (hexValue = 0)
33 return (char)(hexValue + '0');
34 else // hexValue = 10
35 return (char)(hexValue - 10 + 'A');
36 }
37 }