Java Octal轉Binary用法及代碼示例

// Java program to convert
// Octal number to Binary
class OctalToBinary {
    // function to convert octal number
    // to its binary equivalent value
    static String converter(String octalValue)
    {
        // integer variable to iterate
        // the input octal string
        int i = 0;
        // string to store the result
        String binaryValue = "";
        // iterating the complete length
        // of octal string and assigning
        // the equivalent binary value
        // for each octal digit
        while (i < octalValue.length()) {
            // storing character according
            // to the number of iteration
            char c = octalValue.charAt((int)i);
            // switch case to check all
            // possible 8 conditions
            switch (c) {
            case '0':
                binaryValue += "000";
                break;
            case '1':
                binaryValue += "001";
                break;
            case '2':
                binaryValue += "010";
                break;
            case '3':
                binaryValue += "011";
                break;
            case '4':
                binaryValue += "100";
                break;
            case '5':
                binaryValue += "101";
                break;
            case '6':
                binaryValue += "110";
                break;
            case '7':
                binaryValue += "111";
                break;
            default:
                System.out.println(
                    "\nInvalid Octal Digit "
                    + octalValue.charAt((int)i));
                break;
            }
            i++;
        }
        // returning the final result
        return binaryValue;
    }
    // Driver code
    public static void main(String args[])
    {
        System.out.println("Octal to Binary Conversion\n");
        // octal number which is to be converted
        String octalNumber = "315";
        System.out.println("Octal number:" + octalNumber);
        // calling the converter method and
        // storing the result in a string variable
        String result = converter(octalNumber);
        System.out.println("Binary equivalent value is:"
                           + result);
    }
}

// Java program to convert
// Octal number to Binary
public class OctalToBinary {
    // function to convert octal number
    // to its binary equivalent value
    public static int converter(int octalValue)
    {
        // declaring all variable
        // to store the intermediate results
        int i = 0;
        int decimalValue = 0;
        int binaryValue = 0;
        // converting octal number
        // into its decimal equivalent
        while (octalValue != 0) {
            decimalValue
                += (octalValue % 10) * Math.pow(8, i);
            ++i;
            octalValue /= 10;
        }
        i = 1;
        // converting generated decimal number
        // to its binary equivalent
        while (decimalValue != 0) {
            binaryValue += (decimalValue % 2) * i;
            decimalValue /= 2;
            i *= 10;
        }
        // returning the final result
        return binaryValue;
    }
    // Driver code
    public static void main(String[] args)
    {
        System.out.println("Octal to Binary Conversion\n");
        // octal number which is to be converted
        int octalNumber = 315;
        System.out.println("Octal number:" + octalNumber);
        // calling the converter method and
        // storing the result in a string variable
        int result = converter(octalNumber);
        // printing the binary equivalent value
        System.out.println("Binary equivalent value is:"
                           + result);
    }
}

// Java program to convert
// Octal number to Binary
class OctalToBinary {
    // function to convert octal number
    // to its binary equivalent value
    public static String converter(String octalValue)
    {
        // parsing the string value
        // by following octal number system
        int octal = Integer.parseInt(octalValue, 8);
        // converting octal number to binary
        // and storing as a string
        String binaryValue = Integer.toBinaryString(octal);
        // returning the resultant string
        return binaryValue;
    }
    // Driver code
    public static void main(String args[])
    {
        System.out.println("Octal to Binary Conversion\n");
        // octal number which is to be converted
        String octalNumber = "315";
        System.out.println("Octal number:" + octalNumber);
        // calling the converter method and
        // storing the result in a string variable
        String result = converter(octalNumber);
        // printing the binary equivalent value
        System.out.println("Binary equivalent value is:"
                           + result);
    }
}