/* * program can convert decimal to binary and report if an illegal char is * used *program cant convert binary to decimal */ import java.util.Scanner;
/** * This class contains a complete program, with just a main() method, for * converting non-negative decimal integers (ie, base 10 integers) to * positive binary integers (ie, base 2 integers). The values to be * converted are read in from the command line. */ public class BaseConversions2 { public static void main(String[] args) {
//prints the intro to the program if the user does not give any
//numbers
if (args.length == 0)
{
printOpening();
printIntro();
return;
}
//method to check and convert numbers given by the user
runCovert(args);
}
private static void runCovert(String[] args)
{
for (int i = 0; i < args.length; ++i)
{
if (args[i].startsWith("d"))
{
decimalToBinary(args);
++i;
}
else
{
binaryToDecimal(args);
++i;
}
}
}
//method to check if the decimal number the user gave is valid
//if it is convert it
//if not print an error
//method to check if the binary number the user gave is valid
//if it is convert it
//if not print an error
public static void binaryToDecimal(String[] args)
{
for (int i = 0; i < args.length; ++i)
{
String value = args[i].replaceAll("b", "");
// String test = value.replaceAll("\\s+", "");
if (value.matches("[0-1]+"))
{
int test2 = Integer.parseInt(value, 2);
if (test2 >= 0 && test2 <= 11111111111111l)
{
System.out.println("The binary value " + args[i]
+ " is equivalent to the decimal value "
+ test2);
pause();
System.out.println("");
++i;
}
else
{
System.out.println("Error: "
+ "The decimal value " + args[i]
+ " is out of range");
pause();
}
}
else
{
System.out.println("Error: The decimal value "
+ args[i]
+ " has an illegal character in it, ex -+/");
pause();
}
}
}
//method that runs the two conversion methods above
private static void decimalToBinary(String[] args)
{
for (int i = 0; i < args.length; ++i)
{
String value = args[i].replaceAll("d", "");
// String test = value.replaceAll("\\s+", "");
if (value.matches("[0-9]+"))
{
int test2 = Integer.valueOf(value);
if (test2 >= 0 && test2 <= 65535)
{
System.out.println("The decimal value " + args[i]
+ " is equivalent to the binary value "
+ Integer.toBinaryString(test2));
pause();
System.out.println("");
}
else
{
System.out.println("Error: "
+ "The decimal value " + args[i]
+ " is out of range, "
+ "or does not start with the "
+ "letter \"d");
pause();
}
}
else
{
System.out.println("Error: The decimal value "
+ args[i]
+ " has an illegal character in it, ex -+/");
pause();
}
}
}
private static void printIntro()
{
System.out.print("This program allows the user to convert "
+ "either decimal integer values to their\n"
+ "equivalent binary values, or vice versa. "
+ "In either case, it then displays, on\n"
+ "the standard output, a sentence containing "
+ "both the original and the converted\n"
+ "values. Values to be converted are entered on "
+ "the command line, separated by a\n"
+ "blank space. Decimal values must have a d "
+ "as their first character and binary\n"
+ "values must have a b as their first character.");
System.out.println("");
System.out.println("");
System.out.print("The program may convert any number "
+ "of values of either type on any given run.\n"
+ "A value is valid only if it contains just "
+ "those digits allowed by its base,\n"
+ "and lies within the permitted range. "
+ "Our maximum values are: 1111111111111111\n"
+ "for binary, and 65535 for decimal. As numbers, "
+ "these maximum values are equal.\n"
+ "The minimum value in both cases is 0.");
System.out.println("");
System.out.println("");
System.out.println("If any given value does not satisfy the "
+ "necessary criteria, an error must be\n"
+ "reported and the value must be ignored by "
+ "the program, which simply carries\n"
+ "on after reporting the error. In addition, "
+ "if the initial character of a value\n"
+ "is neither b nor d, the program also reports "
+ "the error and carries on.");
System.out.println("");
System.out.println("");
System.out.println("\t\t\t\t\t\t\t\tScreen 1 of 1");
pause();
}
//method to print the opening screen
private static void printOpening()
{
pause();
System.out.println("");
System.out.println("");
}
//method to pause the program
private static void pause()
{
Scanner kbd = new Scanner(System.in);
System.out.print("\n\n\n\nPress Enter to continue ...");
kbd.nextLine();
}
}
i need help working out why my code is not working, basically my code take a binary number and converts it to a decimal and vise versa, however when i put a binary and a decimal numbers in at the same time it say one of them has an illegal character in it and i need to work out why is do this.
i know this is a lot of code but help would really be appreciated as im really stuck right now
` everywhere when that is something you should do with CSS margins... I would need to substantially change my answer as well, not sure I'll have the time right now. I'll delete my answer for now. – domsson Mar 06 '17 at 10:32