class Test { public static void main(String[] args) { int[] array = {7, 8, 12, 41, 13, 98, 12, 18, 15, 72, 65, 90, 39, 40, 81, 10}; long sum = 0; for (int i = 0; i < array.length; i++) { if (array[i] % 2 == 0) { // the way to find out…
Read More Imperative VS Declarative Programming Part 1public class MyCustomException extends RuntimeException { public MyCustomException(String message) { super(message); } } class Test { public static void main(String[] args) { Test test = new Test(); try { test.reserveSeats(8); } catch (MyCustomException e) { System.out.println(“Exception occurred with message: ” + e.getMessage()); } } private void reserveSeats(int numberOfSeats) { if (numberOfSeats > 5) { throw…
Read More Custom Exceptions in Javathrow new Exception(); class Test { public static void main(String[] args) { Test test = new Test(); test.reserveSeats(8); } private void reserveSeats(int numberOfSeats) { if (numberOfSeats > 5) { throw new IllegalArgumentException(“No more than 5 seats can be reserved.”); } else { System.out.println(“Reservation successful!”); } } } Output: Exception in thread “main” java.lang.IllegalArgumentException: No more…
Read More Difference Between throw and throws in Javavoid methodName() throws Exception class Test { public static void main(String[] args) { } private void validateStatus(String status) { if (status.equals(“invalid”)) { throw new IOException(“Status of the file is invalid, the stream is closed!”); } } } class Test { public static void main(String[] args) { Test test = new Test(); test.validateStatus(“valid”); // OK test.validateStatus(“invalid”);…
Read More Java throws Keywordthrow new Exception(); class Test { public static void main(String[] args) { reserveSeat(new User(“Steve”, “Johnson”, false, 32)); // OK reserveSeat(new User(“Mike”, “Lawson”, true, 16)); // Exception will occur } private static void reserveSeat(User user) { if (user.getAge() < 18) { throw new IllegalArgumentException(“The user is under 18 years old!”); } } } class User {…
Read More Throw an Exception in Javatry { //Statements that may cause an exception } catch { //Handling exception } finally { //Statements to be executed } class Test { public static void main(String[] args) { try { System.out.println(20 / 0); // this will throw ArithmeticException } catch (ArithmeticException ae) { System.out.println(“ArithmeticException occurred!”); } finally { System.out.println(“Finally block…”); } } }…
Read More Java finally blockJava try-catch blocks are an essential part of Java programming, used for handling exceptions that might occur during program execution. When used correctly, try-catch blocks can help you write more robust and error-free code. In this tutorial, I will explain what Java try-catch blocks are, how they work, and how to use them effectively. I’ll…
Read More Java Try-Catch Blocks: A Comprehensive GuideException handling is an essential part of any robust software application, and Java is no exception. In Java, an exception is an event that interrupts the normal flow of a program and can occur at runtime. It could be due to various reasons, such as incorrect input, lack of resources, or programming errors. Exception handling…
Read More Master Exception Handling in Javaclass Test { public static void main(String[] args) { long startTime = System.currentTimeMillis(); StringBuffer stringBuffer = new StringBuffer(“Java”); for (int i = 0; i < 8000000; i++) { stringBuffer.append(“Programming”); } System.out.println(“Time taken by StringBuffer: ” + (System.currentTimeMillis() – startTime) + “ms”); startTime = System.currentTimeMillis(); StringBuilder stringBuilder = new StringBuilder(“Java”); for (int i = 0; i…
Read More Difference between StringBuilder and StringBuffer classes// creates an empty string buffer with the initial capacity of 16. StringBuffer str = new StringBuffer(); // creates a string buffer with the specified string. StringBuffer str = new StringBuffer(“some string value”); // creates an empty string buffer with the specified capacity as length. StringBuffer str = new StringBuffer(10); class Test { public static…
Read More StringBuffer class in JavaUp to this point, we’ve discovered that a String object is immutable, which implies that its contents cannot be altered once it is created. When we perform operations on a String, a new String object is generated. In order to modify the contents of a String, we can use the StringBuilder class provided by the…
Read More Master the StringBuilder Class in Javapublic int compareTo(Object obj) class Test { public static void main(String[] args) { List<String> list = new ArrayList<>(); list.add(“Python”); list.add(“Java”); list.add(“JavaScript”); list.add(“Ruby”); list.add(“Kotlin”); System.out.println(“Before sorting:”); System.out.println(list); // sorting the list Collections.sort(list); System.out.println(“After sorting:”); System.out.println(list); } } Output: Before sorting: [Python, Java, JavaScript, Ruby, Kotlin] After sorting: [Java, JavaScript, Kotlin, Python, Ruby] Sorting the array of…
Read More Comparable in JavaQueue queue1 = new LinkedList(); Queue queue2 = new PriorityQueue(); class Test { public static void main(String[] args) { Queue<String> queue = new LinkedList(); queue.offer(“Steve”); queue.offer(“Megan”); queue.offer(“Ryan”); queue.offer(“Melissa”); System.out.println(queue); } } Output: [Steve, Megan, Ryan, Melissa] We can also use the add(Object o) method to add elements to the Queue. In this example, we will…
Read More Queue in JavaHashMap<K, V> map = new HashMap<>(); Map<Integer, String> map = new HashMap<>(); class Test { public static void main(String[] args) { Map<Integer, String> map = new HashMap<>(); map.put(1, “Java”); map.put(7, “Python”); map.put(10, “Ruby”); map.put(3, “Kotlin”); System.out.println(map); } } Output: {1=Java, 3=Kotlin, 7=Python, 10=Ruby} class Test { public static void main(String[] args) { Map<Integer, String> map…
Read More Map in JavaHashSet<String> set = new HashSet<>(); Set<String> set = new HashSet<>(); class Test { public static void main(String[] args) { Set<String> set = new HashSet<>(); set.add(“Java”); set.add(“Kotlin”); set.add(“Python”); set.add(“Ruby”); System.out.println(set); } } Output: [Java, Ruby, Kotlin, Python] class Test { public static void main(String[] args) { Set<String> set = new HashSet<>(); set.add(“Kotlin”); set.add(“Java”); set.add(“Ruby”); set.add(“Python”); Set<String>…
Read More Set in Java