It is not only OK; I’d even recommend it, especially if conditionB is relatively expensive to evaluate. For instance, here’s an alternative way: if(conditionA) { //do A stuff } else if(conditionB && conditionB1) { //do B1 } else if(conditionB && conditionB2) { //do B2 } else if(conditionB && conditionB3) { //do B3 } Let’s say … Read more
Using collections framework in Java, a developer has to use loops and make repeated checks. Another concern is efficiency; as multi-core processors are available at ease, a Java developer has to write parallel code processing that can be pretty error-prone. To resolve such issues, Java 8 introduced the concept of stream that lets the developer … Read more
Consider Apollo’s comment and google it. This is not only a java principle but a generall programming principle. You’re creating a new Answer Object. Let’s look at this example: public class Answer{ // The class private String answer; // internal variable only visible for the class public Answer(String answer){ // This is a constructor this.answer … Read more
Assuming you only continues values(0,1,2,3….) int[] A = {0, 0, 0, 0, 1, 1, 1, 2, 2, 2}; // any number and values will work! int max = IntStream.of(A).max().getAsInt(); // gets max value in array int[] counter = new int[max + 1]; for (int i = 0; i < A.length; ++i) counter[A[i]]++; 4 solved Count … Read more
While your code is really messy (and not easy to read) your problem is that you are adding a different instance of Sc to the Pane rather than adding the one you were drawing on: frame.getContentPane().add(new Sc()); Instead you have to add “this” which you can’t do from a static method, but you can create … Read more
NOTE: Actually technique fabian’s using with Pattern and Matcher is far more correct and elegant, but code provided there is not returning values required by OP . You can use String::split(String). It takes a regular expression to split, so use it, [] means containing one of… so putting | inside will match what you want: … Read more
String constant pool, new object initialization (with new keyword) versus normal initialization of a string? [closed] solved String constant pool, new object initialization (with new keyword) versus normal initialization of a string? [closed]
java.util.InputMismatchException-In order to deal with this exception you must verify that the input data of your application meet its specification. When this error is thrown, the format of the input data is incorrect and thus, you must fix it, in order for your application to proceed its execution. 11 solved error while taking String input … Read more
And how would i make it work form a different class file? Import it, if you need to, and then create an instance of it. how to use the action listeners that are attached to the buttons Place the logic that you’d like to be executed within the actionPerformed(ActionEvent e) method of the ActionListener class … Read more
you can use setter for integer variable as your instance variable age is integer: public void setAge(String a) { try { this.age = Integer.parseInt(a); } catch(NumberFormatException e){ //.. code } } 0 solved Java Programming: Getter/Setter Questions
I/P-a string S.O/P: For each digit start from 0-9,print count of their occurrence in S.Print10 lines,each line contain 2 space separated integers solved I/P-a string S.O/P: For each digit start from 0-9,print count of their occurrence in S.Print10 lines,each line contain 2 space separated integers
I would do it this way (since I love java streams) public static String capitalizeFirstOccurrence(String str) { var alreadyOccurred = new HashSet<String>(); return str.chars() .mapToObj(x -> String.valueOf((char) x)) // convert to single char String .map(character -> { if (alreadyOccurred.contains(character)) { return character; } alreadyOccurred.add(character); return character.toUpperCase(); }) .collect(Collectors.joining()); } public static void main(String[] args) { … Read more
Try using Pattern and Matcher classes from java.util.regex package. Something like this : String data = “[‘first data’,’second data’, ‘third data’]”; Pattern pattern = Pattern.compile(“‘(.*?)'”); Matcher matcher = pattern.matcher(data); while (matcher.find()) { System.out.println(matcher.group(1)); } Output: first data second data third data solved How do I parse and split data in single quotation mark using Java?
Not quite clear on your code, but when you remove an element from an ArrayList that you are iterating through, you do not want to increment the index, otherwise you will skip elements, e.g.: ArrayList<…> list = …; for (int i = 0; i < list.size(); ) { if (shouldBeRemoved) list.remove(i); else ++ i; } … Read more
super() calls the parent constructor of the class and this() calls the constructor defined within the class. //Example of super() class parent { parent() { } } class child() { child() { super(); //Go to parent class constructor } } //Example of this class test { test() { this(“a”); //go to test one argument constructor … Read more