Course
Introduction
Print an Integer (Entered by the User)Add Two IntegersMultiply two Floating Point NumbersFind ASCII value of a characterCompute Quotient and RemainderSwap Two NumbersCheck Whether a Number is Even or OddFind the Frequency of Character in a StringRemove All Whitespaces from a StringRound a Number to n Decimal PlacesDecision Making and Loop
Check Whether an Alphabet is Vowel or ConsonantFind the Largest Among Three NumbersFind all Roots of a Quadratic EquationCheck Leap YearCheck Whether a Number is Positive or NegativeCheck Whether a Character is Alphabet or NotCalculate the Sum of Natural NumbersFind Factorial of a NumberGenerate Multiplication TableDisplay Fibonacci SeriesFind GCD of two NumbersFind LCM of two NumbersDisplay Characters from A to Z using loopCount Number of Digits in an IntegerReverse a NumberCalculate the Power of a NumberCheck Whether a Number is Palindrome or NotCheck Whether a Number is Prime or NotDisplay Prime Numbers Between Two IntervalsCheck Armstrong NumberDisplay Armstrong Number Between Two IntervalsDisplay Factors of a NumberMake a Simple Calculator Using switch...caseCount the Number of Vowels and Consonants in a SentenceSort Elements in Lexicographical Order (Dictionary Order)Create Pyramid and PatternFunctions
Display Prime Numbers Between Intervals Using FunctionDisplay Armstrong Numbers Between Intervals Using FunctionCheck Whether a Number can be Expressed as Sum of Two Prime NumbersFind the Sum of Natural Numbers using RecursionFind Factorial of a Number Using RecursionFind G.C.D Using RecursionConvert Binary Number to Decimal and vice-versaConvert Octal Number to Decimal and vice-versaConvert Binary Number to Octal and vice-versaReverse a Sentence Using Recursioncalculate the power using recursionArrays
Calculate Average Using ArraysFind Largest Element in an ArrayCalculate Standard DeviationAdd Two Matrix Using Multi-dimensional ArraysMultiply to Matrix Using Multi-dimensional ArraysMultiply two Matrices by Passing Matrix to a FunctionFind Transpose of a MatrixPrint an ArrayConcatenate Two ArraysConvert Character to String and Vice-VersaCheck if An Array Contains a Given ValueCollections
Join Two ListsConvert List (ArrayList) to Array and Vice-VersaConvert Map (HashMap) to ListConvert Array to Set (HashSet) and Vice-VersaSort a Map By ValuesObject and Class
Add Two Complex Numbers by Passing Class to a FunctionCalculate Difference Between Two Time PeriodsAdvanced
Convert String to DateGet Current Date/TImeConvert Milliseconds to Minutes and SecondsAdd Two DatesGet Current Working DirectoryConvert Byte Array to HexadecimalCreate String from Contents of a FileAppend Text to an Existing FileConvert a Stack Trace to a StringConvert File to byte array and Vice-VersaConvert InputStream to StringConvert OutputStream to StringLookup enum by String valueCompare StringsSort ArrayList of Custom Objects By PropertyCheck if a String is NumericJava Program to Convert Byte Array to Hexadecimal
To understand this example, you should have the knowledge of the following Java programming topics:
Example 1: Convert Byte Array to Hex value
public class ByteHex {
public static void main(String[] args) {
byte[] bytes = {10, 2, 15, 11};
for (byte b : bytes) {
String st = String.format("%02X", b);
System.out.print(st);
}
}
}
Output
0A020F0B
In the above program, we have a byte array named bytes. To convert byte array to a hex value, we loop through each byte in the array and use String’s format().
We use %02X to print two places (02) of Hexadecimal (X) value and store it in the string st.
This is a relatively slower process for large byte array conversion. We can dramatically increase the speed of execution using byte operations shown below.
Example 2: Convert Byte Array to Hex value using byte operations
public class ByteHex {
private final static char[] hexArray = "0123456789ABCDEF".toCharArray();
public static String bytesToHex(byte[] bytes) {
char[] hexChars = new char[bytes.length * 2];
for ( int j = 0; j < bytes.length; j++ ) {
int v = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[v >>> 4];
hexChars[j * 2 + 1] = hexArray[v & 0x0F];
}
return new String(hexChars);
}
public static void main(String[] args) {
byte[] bytes = {10, 2, 15, 11};
String s = bytesToHex(bytes);
System.out.println(s);
}
}
The output of the program is the same as Example 1.