Object Oriented Programming Articles - Page 847 of 915

We can verify whether the given string is empty using the isEmpty() method of the String class. This method returns true only if length() is 0.ExampleLive Demoimport java.lang.*; public class StringDemo {    public static void main(String[] args) {       String str = "tutorialspoint";       // prints length of string       System.out.println("length of string = " + str.length());       // checks if the string is empty or not       System.out.println("is this string empty? = " + str.isEmpty());    } }Outputlength of string = 14 is this string empty? = false

The replace method of the String class accepts two characters and it replaces all the occurrences of oldChar in this string with newChar.Exampleimport java.io.*; public class Test {    public static void main(String args[]) {       String Str = new String("Welcome to Tutorialspoint.com");       System.out.print("Return Value :" );       System.out.println(Str.replace('o', 'T'));       System.out.print("Return Value :" );       System.out.println(Str.replace('l', 'D'));    } }OutputReturn Value :WelcTme tT TutTrialspTint.cTm Return Value :WeDcome to TutoriaDspoint.comThe replaceAll() method replaces each substring of this string that matches the given regular expression with the given replacement.Exampleimport java.io.*; ... Read More

A string is a collection of characters. In Java, it is represented by the String class, and it accepts NULL values. Checking for Null or Empty in Java In this article, we will learn if a string is null or empty in Java. The following are the ways to check if a string is null or empty in Java: Using isEmpty() Method Using length() Method Using isBlank() Method Using isEmpty() Method The isEmpty() method of the String class checks if a string is empty. It returns TRUE if ... Read More

The replace method of the String class accepts two characters and it replaces all the occurrences of oldChar in this string with newChar.Example Live Demoimport java.io.*; public class Test {    public static void main(String args[]) {       String Str = new String("Welcome to Tutorialspoint.com");       System.out.print("Return Value :" );       System.out.println(Str.replace('o', 'T'));       System.out.print("Return Value :" );       System.out.println(Str.replace('l', 'D'));    } }OutputReturn Value :WelcTme tT TutTrialspTint.cTm Return Value :WeDcome to TutoriaDspoint.com

The isEmpty() method of the String class returns true if the length of the current string is 0.ExampleLive Demoimport java.lang.*; public class StringDemo {    public static void main(String[] args) {       String str = "tutorialspoint";       //prints length of string       System.out.println("length of string = " + str.length());       //checks if the string is empty or not       System.out.println("is this string empty? = " + str.isEmpty());    } }Outputlength of string = 14 is this string empty? = false

We can verify whether the given string is empty using the isEmpty() method of the String class. This method returns true only if length() is 0.ExampleLive Demoimport java.lang.*; public class StringDemo {    public static void main(String[] args) {       String str = "tutorialspoint";       // prints length of string       System.out.println("length of string = " + str.length());       // checks if the string is empty or not       System.out.println("is this string empty? = " + str.isEmpty());    } }Outputlength of string = 14 is this string empty? = false

In this article, we will learn how to convert all characters in a string to uppercase using the toUpperCase() method in Java. This method has two versions: one that uses the system's default language settings and another that lets you choose a specific language. Changing string characters to uppercase helps keep the text consistent, especially for usernames or titles. Problem StatementGiven a string, write a Java program to convert all its characters to uppercase using the toUpperCase() method.Input Initial String = "Welcome to Tutorialspoint.com"Output Converted String = "WELCOME TO TUTORIALSPOINT.COM" Steps to convert a string to uppercase The ... Read More

The contains() method of the String class returns true if and only if this string contains the specified sequence of char values.Example Live Demoimport java.lang.*; public class StringDemo {    public static void main(String[] args) {       String str1 = "tutorials point", str2 = "http://";       CharSequence cs1 = "int";             //string contains the specified sequence of char values       boolean retval = str1.contains(cs1);       System.out.println("Method returns : " + retval);             //string does not contain the specified sequence of char value       retval = str2.contains("_");       System.out.println("Methods returns: " + retval);    } }OutputMethod returns : true Methods returns: false

The toCharArray() method of a String class converts this string to a character array.ExampleLive Demoimport java.lang.*; public class StringDemo {    public static void main(String[] args) {       // converts String value to character array type value       String str = " Java was developed by James Gosling";       char retval[] = str.toCharArray();       // displays the converted value       System.out.println("Converted value to character array = ");       System.out.println(retval);    } }OutputConverted value to character array = Java was developed by James Gosling

The StringTokenizer class of the java. util package allows an application to break a string into tokens.This class is a legacy class that is retained for compatibility reasons although its use is discouraged in new code.Its methods do not distinguish among identifiers, numbers, and quoted strings.These class methods do not even recognize and skip comments.ExampleLive Demoimport java.util.*; public class Sample {    public static void main(String[] args) {       // creating string tokenizer       StringTokenizer st = new StringTokenizer("Come to learn");       // checking next token       System.out.println("Next token is : " + st.nextToken());    } }OutputNext token is : Come