Use the trim() method to remove whitespace from the beginning and end of a string.Let’s say the following is our string with whitespace.str1 = " The Big Bang Theory ";Now, let us trim all the whitespaces from the beginning and the end.String str2 = str1.trim();The following is the final example with output.Example Live Demopublic class Demo {    public static void main(String[] args) {       String str1 = " The Big Bang Theory ";       System.out.println("String: "+str1);       String str2 = str1.trim();       System.out.println("Updated string (trimming spaces): "+str2);    } }OutputString: The Big ... Read More

Use the replace() method to replace a specific character with another. Let’s say the following is our string and here we are replacing a whitespace with a $ character.String str1 = "Orange is the new Black!";Now, use the replace() method to replace a character with $str1.replace(' ', '$');Example Live Demopublic class Demo {    public static void main(String[] args) {       String str1 = "Orange is the new Black!";       System.out.println("String: "+str1);       String str2 = str1.replace(' ', '$');       System.out.println("Updated string: "+str2);    } }OutputString: Orange is the new Black! Updated string: ... Read More

To access character of a string in Java, use the charAt() method. The position is to be added as the parameter.Let’s say we have the following string −String str = "laptop";Let’s find the character at the 4th position using charAt() method.str.charAt(3));The following is the final example.Example Live Demopublic class Demo {    public static void main(String[] args) {       String str = "laptop";       System.out.println("String: "+str);       // finding character at 4th position       System.out.println("Character at 4th position: "+str.charAt(3));    } }OutputString: laptop Character at 4th position: t

An array can be reversed upto the given position pos and the remaining array is unchanged. An example of this is given as follows −Array = 1 2 3 4 5 6 7 8 9 10 Position = 6 Modified array = 6 5 4 3 2 1 7 8 9 10A program that demonstrates this is given as follows −Example Live Demopublic class Example {    public static void main(String args[]) {       int[] arr = {1, 2, 3, 4, 5, 6, 7 ,8 ,9, 10};       int n = arr.length;       int pos ... Read More

A program can be created to check if a string is a correct URL or not. An example of an URL is given as follows −String = https://www.wikipedia.org/ The above string is a valid URLA program that demonstrates this is given as follows.Example Live Demoimport java.net.URL; public class Example {    public static boolean check_URL(String str) {    try {       new URL(str).toURI();       return true;    }catch (Exception e) {       return false;    } } public static void main(String[] args) {    String str = "http://www.wikipedia.org/";    System.out.println("String = " + str);   ... Read More

A string is a Heterogram if no letter of the alphabet occurs more than once in it. An example of this is given as follows −String = the big dwarf only jumpsThis string is a Heterogram as each alphabet in the string occurred only once.A program that demonstrates this is given as follows.Example Live Demopublic class Example {    public static void main (String[] args) {       String str = "mango";       int n = str.length();       int alphaList[] = new int[26];       int flag = 1;       System.out.println("The string is: ... Read More

Let’s say we have the following string −String myStr1 = "Jack Sparrow";Let us check the string now whether it is not null or not empty.if(myStr != null || myStr.length() != 0) { System.out.println("String is not null or not empty");Example Live Demopublic class Demo {    public static void main(String[] args) {       String myStr = "Jack Sparrow";       boolean res;       if(myStr != null || myStr.length() != 0) {          System.out.println("String is not null or not empty");       } else {          System.out.println("String is null or empty");       }    } }OutputString is not null or not empty

Each word in a sentence can be reversed and the sentence displayed with the words in the same order as before. An example of this is given as follows −Original sentence = an apple is red Modified sentence = na elppa si derA program that demonstrates this is given as follows.Example Live Demopublic class Example { public static void main(String[] args) { String str = "the sky is blue"; System.out.println("The original string is: " + str); String strWords[] = str.split("\s"); String rev = ""; for(String sw : strWords) { StringBuilder sb = new StringBuilder(sw); sb.reverse(); rev += sb.toString() + " "; ... Read More

Import the following package for Calendar class in Java.import java.util.Calendar;Firstly, create a Calendar object and display the current date and time.Calendar calendar = Calendar.getInstance(); System.out.println("Current Date and Time = " + calendar.getTime());Now, let us increment the seconds using the calendar.add() method and Calendar.SECOND constant.calendar.add(Calendar.SECOND, 15);Example Live Demoimport java.util.Calendar; public class Demo {    public static void main(String[] args) {       Calendar calendar = Calendar.getInstance();       System.out.println("Current Date = " + calendar.getTime());       // Add 15 seconds to current date       calendar.add(Calendar.SECOND, 15);       System.out.println("Updated Date = " + calendar.getTime());    } ... Read More

When working with dates in Java, it's common to need to increment or decrement months. The Calendar class makes it easy to manipulate dates. This article shows how to decrement the current date by a specified number of months using the Calendar class. Problem Statement Given a Java program to decrement the current date by a specified number of months using the Calendar class. Output Current Date = Thu Nov 22 16:37:42 UTC 2018 Updated Date = Thu Mar 22 16:37:42 UTC 2018 Basic Approach Below are the steps to subtract months from current date using Calendar.add() ... Read More