Can I use the door leading from Vatican museum to St. Peter's Basilica? Not the answer you're looking for? I recommend the following: int index = 0; int count = 0; while (chain.indexof (character, index) != -1 && index < chain.length ()-1) { index = chain.indexof (character . How do I convert a String to an int in Java? Viewed 773k times 770 I'm looking for a simple commons method or operator that allows me to repeat some string n times. The Apache Commons API provides powerful and reusable Java components and dependencies that we can embed into our applications and programs. I am a java beginner, please keep that in mind. I created a recursive method that do the same thing you want.. feel free to use this i have the same answer on Can I multiply strings in java to repeat sequences? Can you please add a description of why you believe this answers the question? You can make the solution less ugly and easier to understand: @MonoThreaded I thought it would go without saying, but don't include guava just to do a string repeat. Can a judge or prosecutor be compelled to testify in a criminal trial in which they officiated? I recommend the following: Contains will simply tell you if the character is present. .contains() only says that a character exists within a string, not how many. You could also repeatedly check that the character is in the string, get that index, then check the substring from after that index to the end of the string. Well, there are three ways to handle if s is null. A lot less garbage and string copying will be involved which probably means better performance overall. I'm talking about the c in the original question, not in your answer, The Stream approach is indeed not an advantage. Using lastIndexOf() Method to Find Char in String in JavaFind Character at Index in String in Javahow Do I Find Word in String in Java? 4 reviews. So we will take a deep dive into looking at various ways to solve this problem, starting from the simplest approach to digging deep into how many approaches to ace our concepts. 555. Given that a for-loop is the idiomatic way to do this, it would be much easier to figure out if you did it with a for loop. Why do code answers tend to be given in Python when no language is specified in the prompt? This creates n new string instances containing 1 to n repetitions of s resulting in a runtime of O(s.length() * n) = O(s.length() * (1+2++(n-1)+n)). By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Thus it is required to work with arrays of chars. What Is Behind The Puzzling Timing of the U.S. House Vacancy Election In Utah? But as you can see the .contains only counts the character once, not the number of times it appears in the string. [], Table of ContentsHow to Find Character in String in Java1. How to generate random characters without repeating? Find centralized, trusted content and collaborate around the technologies you use most. In this post, we will see how to find character [], Your email address will not be published. The string can be repeated N number of times, and we can generate a new string that has repetitions. The syntax of the method is : public static String format(String format, Object args). String#repeat(int count), introduced as part of Java SE 11, makes it quite easy to do. That's not the for-loop's fault. Here is the shortest version (Java 1.5+ required): Where n is the number of times you want to repeat the string and s is the string to repeat. This article discusses methods to remove parentheses from a String in Java. T is the generic type. but commons lang is just too big if it's a small project. Using regular expression to find at least one repeating character in a string. It's seems to be the cleanest way without using any external API oder utility method! // Return the String if it is empty or null. Unless it's in some piece of code that will be executed thousands of times per second it won't make much difference. OverflowAI: Where Community & AI Come Together, Create NSString by repeating another string a given number of times, hg.openjdk.java.net/jdk/jdk/file/fc16b5f193c7/src/java.base/, download.oracle.com/javase/1.5.0/docs/api/java/lang/, stackoverflow.com/questions/47605/java-string-concatenation. To do this we use the Arrays.fill () method. Java Stream reuse traverse stream multiple times? How do I create a repeated sequence of character? | Kode Java What mathematical topics are important for succeeding in an undergrad PDE course? While working with string there can be a need of repeating a string, for that purpose, Java provides repeat() method in String class. We had a look at different examples with the code. 594), Stack Overflow at WeAreDevelopers World Congress in Berlin, Temporary policy: Generative AI (e.g., ChatGPT) is banned, Preview of Search and Question-Asking Powered by GenAI. If the string is empty or the count is zero then the empty string is returned. Ex: String, Object, etc. This tutorial shows different ways to repeat an input string n number of times. @tecnotron I know, but still they are better than nothing And the only 'surprise' was the slight difference between the naive loop concatenation and linear recursion. Rather saying that by writing less code, and using library functions rather than reinventing the wheel I reduce the bug surface area(Lines of Code) while increasing readability. With java-8, you can also use Stream.generate. Frankfurt, Germany. By Wayan in Core API, Util Package Last modified: May 14, 2023 0 Comment This example show you how to create a repeated sequence of characters. So e5, I think the best way to do this would be to simply use the above mentioned code,or any of the answers here. string - java repeat character - Stack Overflow This method returns a string whose value is the concatenation of given string repeated count times. Here, we are creating a string using a char array and replacing the array's default value by the provided string. answer taken form Simple way to repeat a String in java so vote up there. With the advent of Java 8, the Collection Framework was introduced in java. Java has a repeat function to build copies of a source string: String newString = "a" .repeat (N); assertEquals (EXPECTED_STRING, newString); This allows us to repeat single characters, or multi-character strings: String newString = "-->" .repeat ( 5 ); assertEquals ( "-->-->-->-->-->", newString); See. Effect of temperature on Forcefield parameters in classical molecular dynamics simulations. Not the answer you're looking for? I makes sense that the second one would take much longer. My edited answer is loop-free as requeted. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. for loop print - as many as the word length? It was designed for building up strings from parts. On each iteration we will concatenate the result string with the given string like this: If the input String is null or the counter N = 0, we simply return the string. How do I use StringTokenizer to split a string? OverflowAI: Where Community & AI Come Together. Connect and share knowledge within a single location that is structured and easy to search. I don't think this is so inefficient either, string concatenation isn't the warcrime it once was, because + really is just a stringBuilder UTH. How to help my stubborn colleague learn new ways of coding? Previous owner used an Excessive number of wall anchors, Manga where the MC is kicked out of party and uses electric magic on his head to forget things. They are very often easy to get wrong. This is perfectly clear in what it does and educational for those who may not see it right away. Probably obvious, but you can call this method on a string literal too: using a one-method-dependency for the simplicity's sake in the long run can resulting in a jar-hell. Data Structure & Algorithm Classes (Live), Data Structure & Algorithm-Self Paced(C++/JAVA), Full Stack Development with React & Node JS(Live), Top 100 DSA Interview Questions Topic-wise, Top 20 Interview Questions on Greedy Algorithms, Top 20 Interview Questions on Dynamic Programming, Top 50 Problems on Dynamic Programming (DP), Commonly Asked Data Structure Interview Questions, Top 20 Puzzles Commonly Asked During SDE Interviews, Top 10 System Design Interview Questions and Answers, Indian Economic Development Complete Guide, Business Studies - Paper 2019 Code (66-2-1), GATE CS Original Papers and Official Keys, ISRO CS Original Papers and Official Keys, ISRO CS Syllabus for Scientist/Engineer Exam. java - Finding a repeated character in a string - Stack Overflow Replace space with underscore in java 1. Webdriver simplest way to enter a longstring with sendKeys? Your email address will not be published. In this demo, i will show you how to create a instagram login page using html and css. Help us improve. N Channel MOSFET reverse voltage protection proposal. Has these Umbrian words been really found written in Umbrian epichoric alphabet? Indeed keep at least the entire code English (all identifiers; classnames, methodnames, variablenames). Throw an NPE. I really enjoy this question. By clicking Post Your Answer, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct. This method is added to the String class with the Java 11 version. So here's the code if anybody wants to try it: It takes 2 arguments, the first is the number of iterations (each function run with repeat times arg from 1..n) and the second is the string to repeat. Note: JDK 11.0 or higher must be installed on your machine to use this API. As the result you get the x character repeated 10 times. New! It is not a huge difference. We will also shed some light on the concept of UUID, its use, and its corresponding representation in Java class. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); document.getElementById( "ak_js_2" ).setAttribute( "value", ( new Date() ).getTime() ); HowToDoInJava provides tutorials and how-to guides on Java and related technologies. @imagist I'm avoiding for loops in situations where it costs me readability, and maintainability. String s = "qwe"; int n = 3; //this line print 'qweqweqwe'. Please, never return null - in that case return an empty string, allowing you to always use the returned value unchecked. After this, we can just use the import statement to embed the StringUtils class from the Apache Commons Lang package. Only with the exception if it concerns a piece of code that will be executed many times per second. By using our site, you You need to iterate over each character of a string to check if it equals the character you are searching for. Along with this, the Collections class was introduced that provided static methods to operate on the Collection and return the collection. What is the latent heat of melting for a everyday soda lime glass. There are several ways to repeat to a string like using nCopies() method of Collections class or repeat() method or replace() method of string can also be used to get repeat string. Next, we will replace each value in the array with the input String. For our ease, we will use the JAR file component of the Apache Commons Lang package. Global control of locally approximating polynomial in Stone-Weierstrass? They don't have to worry that I attempted to write my own version of repeat and made a mistake. 1 year ago. 2. Please use English (even in code) when asking questions on an English forum. You will be notified via email once the article is available for improvement. If you only know the length of the output string (and it may be not divisible by the length of the input string), then use this method: Don't use with empty s and length > 0, since it's impossible to get the desired result in this case. @TsuyoshiIto You use O() according to a unit operation you define. The string can be repeated N number of times, and we can generate a new string that has repetitions. 1. So far, a quick inspection of the times running with different inputs leaves the ranking something like this (better to worse): I wouldn't ever guessed that the recursive function was faster than the for loop :-o, This contains less characters than your question. No third-party libraries needed. New in Java 11 is the method String::repeat that does exactly what you asked for: Java 8's String.join provides a tidy way to do this in conjunction with Collections.nCopies: Here's a way to do it using only standard String functions and no explicit loops: If you're like me and want to use Google Guava and not Apache Commons. Again, so does whatever solution you use. It's difficult to see what you are doing without that. Of course it has a loop inside, but it's not quite as simple. Your testing methodology is flawed. The nice thing about this method is that with join you can provide a separator character which works out to be very handy if you are, say, building up a CSV list. Connect and share knowledge within a single location that is structured and easy to search. 1. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Heck, write your own Util Class and reuse it. A programmer, recreational runner and diver, live in the island of Bali, Indonesia. Replace comma with space in java 1. // then we replace number 0 with original string str to repeat 6 times. This site uses Akismet to reduce spam. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. What is telling us about Paul in Acts 9:1? Using a pre-sized StringBuilder will get closer to the ideal. In that case. Here is syntax of replace() method: [crayon-64c573bd68b3d408419238/] [crayon-64c573bd68b46456059485/] Output: 1 [], Table of ContentsJava StringsRemove Parentheses From a String Using the replaceAll() MethodRemove Parentheses From a String by TraversingConclusion Java uses the Strings data structure to store the text data. Connect and share knowledge within a single location that is structured and easy to search. Best solution? The StringUtils class provides the repeat() method as well to repeat a particular input String as we saw in earlier examples. public static void main(String[] args) {. Repeating a string. 1. Here is an example, that repeats the string 'fox' 5 times. How do I convert primitive data types into String? a straightforward one-line solution: For loops increase the number of places a bug hunter has to look. The following Class can be used either with or without Separator-String/CharSequence and each call to "toString()" builds the final repeated String. After 1 million iterations, the garden-variety StringBuilder took 2 seconds (fun1), and the cryptic supposedly more optimal version (fun2) took 30 seconds. We will run a loop N times that is given as input. How to repeat string n times in java? - The code examples Big-O, not LoC. It doesn't really matter. "Pure Copyleft" Software Licenses? Can Henzie blitz cards exiled with Atsushi? Ltd. Interactive Courses, where you Learn by writing Code. extends CharSequence> and Collections#nCopies(int, T): A simple and clean solution would be to use String.format and then replace characters with desired character. How do I efficiently iterate over each entry in a Java Map? To set up the JAR file component for this package we follow the steps mentionedhere. Making statements based on opinion; back them up with references or personal experience. The String class in Java is used to create and implement string objects. In the format() method we pass the String as a text to format a number. It is performing a string search and then modifying the string character by character. How to Convert Comma Separated String to HashSet in Java? Could the Lightning's overwing fuel tanks be safely jettisoned in flight? How to handle repondents mistakes in skip questions? By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. String repeat() - Repeat string N times in Java - HowToDoInJava I would never make a choice based on such microscopic optimizations instead of legibility in Java. Here, we are using replace() method that is used to replace string but with some logical code, we can use it to repeat string. This method will work: you can achieve your goal this way you're taking the integer s without any reason and what you're doing wrong is you are using .contains() method instead of that you should compare the given char with each char of the string and use a counter for maintaining number of times of the character or you can do it this way by converting the char into a string by concatenating it with an empty string("") and then use .equals method like i have used in my code. Contribute to the GeeksforGeeks community and help create better learning resources for all. Not the answer you're looking for? You can use the repeat method in the Guava Strings class. How to help my stubborn colleague learn new ways of coding? Making statements based on opinion; back them up with references or personal experience. It should hardly matter in any but the most demanding circumstances. It accepts two parameters: n -> the number of copies to make and the object to copy. I know I could write this using a for loop, but I wish to avoid for loops whenever necessary and a simple direct method should exist somewhere. (It is not in Internet Explorer .) Slightly more optimization than the other one, though still bad nevertheless. I really have a hard time seeing how anyone could read what I wrote and seriously think the responses typed above. Thanks for contributing an answer to Stack Overflow! rev2023.7.27.43548. Unless you're already using Apache Commons, this answer is a lot less hassle - no downloading another library, including it in your classpath, making sure its license is compatible with yours, etc. In normal times we should be ok I think, but what are your COVID/holiday expectations? Is it unusual for a host country to inform a foreign politician about sensitive topics to be avoid in their speech? This is what you get with Java by the way. Messages can be kept in Dutch, but preferably add an English comment to make it clear. Using replace() method Use Strings replace() method to replace comma with space in java. Using Stream API to Repeat String N Times in Java, StringUtils Package Apache Commons Library to Repeat String N Times in Java. To test speed, a similar optimal method using StirngBuilder is like this: Note that the test for loop is to kick in JIT and have optimal results. Then, we replace the formatted string with the original string. Using replace() method2. For example, "a".concat("b") is "ab". Since the default value of each element in the char array is null we replace. This is an iterative way to solve this problem. 594), Stack Overflow at WeAreDevelopers World Congress in Berlin, Temporary policy: Generative AI (e.g., ChatGPT) is banned, Preview of Search and Question-Asking Powered by GenAI. Asking for help, clarification, or responding to other answers. The method throws IllegalArgumentExceptionif the count is negative. I try to avoid for loops when they are not completely necessary because: They add to the number of lines of code even if they are tucked away in another function. And it's worth noting: the code above does not contain an off-by-one error. Java - Create a new String instance with specified length and filled with specific character. Java Strings Java Strings is a class that stores the text data at contiguous [], Table of ContentsEscape Percent Sign in Strings Format Method in JavaEscape Percent Sign in printf() Method in Java In this post, we will see how to escape Percent sign in Strings format() method in java. public class Main { public static void main (String [] args) { String str = "Studytonight"; System.out.println (str); // Repeat String String newStr = str.repeat (3); System.out.println (newStr); } } Studytonight Add a comment. rev2023.7.27.43548. To learn more, see our tips on writing great answers. Connect and share knowledge within a single location that is structured and easy to search. //With out string methods. This is the approach I would take but why do more checks than is needed? Did active frontiersmen really eat 20,000 calories a day? How to repeat String N times in Java - Studytonight rev2023.7.27.43548. Find centralized, trusted content and collaborate around the technologies you use most. Despite your desire not to use loops, I think you should use a loop. Let us know if you liked the post. into a utility class in your project. Frankfurt Airport, like many others around the world, saw huge delays at baggage delivery and security last year in the summer. Using replace() method2. Printing a string N times We can do this in various ways. @e5;sorry for posting years later.I find this question so appropriate. 'repeat' could simply be rewritten using a StringBuilder (setting the initial capacity). final int n = . Behind the scenes with the folks building OverflowAI (Ep. But you shouldn't try to avoid for loops "at all costs" because if it costs you readability, maintainability, and speed, you're being counterproductive. Is Java "pass-by-reference" or "pass-by-value"? returning a String with X repeated characters without a loop, Construct a string from a repeated character. Someone reading my code has to figure out what I am doing in that for loop. Returns: String whose value is the concatenation of given String repeated count times. If inserted in a method, arguments should be tested (times>=0), errors thrown etc.This adds robustness but also lines of code to read. Enhance the article with your expertise. acknowledge that you have read and understood our. Asking for help, clarification, or responding to other answers. With all the other methods you have a terminating joining character that needs to be stripped out in a separate operation. How can I identify and sort groups of text lines separated by a blank line? string + repeat(string, number-1) : ""; @Fering main reason so that this way is O(log N) average rather than O(N) always. replacing tt italic with tt slanted at LaTeX level? Using ThreadPoolExecutor in MultiThreaded applications. Thank you for your valuable feedback! This implementation will unnecessarily create a new StringBuilder (and a new String) for each recursion. Problem: Create a String containing n repetitions of a String s. The trivial approach would be repeatedly concatenating the String. Stay Up-to-Date with Our Weekly Updates. Learn to repeat a given string N times, to produce a new string which contains all the repetitions, though a simple Java program. Learn, how to repeat a string n times in Java. In response to your criticisms: here is the latest Stringutils.java StringUtils.java. In this demo, i will show you how to create a snow fall animation using css and JavaScript. 11 Answers Sorted by: 48 int n = 10; char [] chars = new char [n]; Arrays.fill (chars, 'c'); String result = new String (chars); EDIT: It's been 9 years since this answer was submitted but it still attracts some attention now and then. Trying to measure the speed of your implementations like that is not good. repeat string javascript Using indexOf() Method to Find Character in String in Java2. In Java, with the String replace()methodwe can define a Regular expression or a regex to modify any String. Let us have a quick look [], Table of ContentsReplace space with underscore in java1. I don't think it's obfuscated at all. It basically has the implementation of a character array. If you are working on JDK <= 10, then you may consider using regex to repeat a string N times. Java Language Tutorial => Repeat a String n times Generating a Java String of N Repeated Characters | Baeldung 2023 Studytonight Technologies Pvt. In the meantime Java 8 has been introduced with functional programming features. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. and you can wrap it in a simple utility method if needed: (of course I know this is ugly and inefficient, but it doesn't have loops :-p). Thats the only way we can improve. I have to make a program that reads a number, and then displays that amount of exclamation mark "!". 594), Stack Overflow at WeAreDevelopers World Congress in Berlin, Temporary policy: Generative AI (e.g., ChatGPT) is banned, Preview of Search and Question-Asking Powered by GenAI. Learn how your comment data is processed. Find centralized, trusted content and collaborate around the technologies you use most.
Mpssaa 3a State Track And Field Championships,
Men's Long Board Shorts With Pockets,
How To Use Prayer As A Weapon,
Da Kine Pronunciation Hawaiian,
Hernandez Elementary School,
Articles J
