Strings are used to store a sequence of characters in Java, they are treated as objects. The String class of the java.lang package represents a String.You can create a String either by using the new keyword (like any other object) or, by assigning value to the literal (like any other primitive datatype).String stringObject = new String("Hello how are you"); String stringLiteral = "Welcome to Tutorialspoint";Concatenating StringsYou can concatenate Strings in Java in the following ways −Using the "+" operator − Java Provides a concatenation operator using this, you can directly add two String literalsExampleimport java.util.Scanner; public class StringExample {   ... Read More

We can use the method below to read the contents of a file in Java: Using the java.util.Scanner class. Using the java.io.BufferedReader class. Using the java.nio.file.Files class. Using the Scanner class In Java, you can read the contents of a file in several ways. One way is to read it into a string using the java.util.Scanner class, to do so, follow the steps below: Instantiate the Scanner class, with the path of the file to be read, as a parameter to its constructor. Create an empty String buffer. Start a while loop with a condition, if the ... Read More

In this article, we will learn how to split a string on a fixed character sequence in Java. We have multiple ways to split a string in Java. Some of them are as follows: Using the split() method of the String class. Using the substring() method of the String class. Using the StringTokenizer class. Let's discuss each of them in detail one by one. Using the split() method of the String class The split() method of the String class accepts a delimiter (in the form of a string), divides the current String into smaller strings based on the ... Read More

Since Java8 StringJoiner class is introduced this you can construct a sequence of characters separated by desired delimiter.Sr.NoConstructor & Description1StringJoiner(CharSequence delimiter)This constructor creates an empty (no characters) StringJoiner, just with a copy of the specified delimiter.2StringJoiner(CharSequence delimiter, CharSequence prefix, CharSequence suffix)This constructs a StringJoiner without characters.Methods of StringJoiner classadd() − This method accepts a CharacterSequence object (Segment, String, StringBuffer, StringBuilder) and adds it to the current Joiner separating the next and previous elements (if any) with delimiter at the time of constructing it.Exampleimport java.util.StringJoiner; public class StringJoinerExample {    public static void main(String args[]) {       StringJoiner joiner ... Read More

In this article, we will learn how to find a unique character in a string in Java. A unique character is a character that occurs only once in the string, while all others can occur multiple times. We can solve this problem using the following ways: Using Brute Force method. Using HashMap. Using brute force method To find a unique character in a given string, we will use a brute force approach. In the brute force approach, we will use two loops to compare each character to the rest of the string. Let's look at the steps: ... Read More

In this article, we will learn to extract all the words that start with a vowel and have a length equal to n from a given text file or string in Java. We can solve this problem using the following ways: Using the split() method of the String class. Using the StringTokenizer class. Using Regular Expressions. Using the split() method of the String class To extract all the words that start with a vowel and have a length equal to n from a given text file or string in Java, we can use the following steps: The ... Read More

In this article, we will see how to extract an HTML tag from a string using regex in Java. We can achieve this in multiple ways, but if we use regex, it will be better than others and also give us fast performance. What is Regex? Regex is a sequence of characters that describes a search pattern that is used to find a particular pattern in a String. It is also known as a regular expression or regexp. We use regex for pattern matching or searching or replacing a String. We will use the java.util.regex package of Java that provides ... Read More

Automatic resource management(ARM) or try-with-resources is a new exception handling mechanism that we are going to discuss in this article. What is a resource? A resource is an object which implements AutoClosable interface. Whenever you use a resource in your program, it is recommended to close it after use. For example, if you open a file using FileInputStream, it is recommended to close the stream after usage. This is done to free up the system resources. In Java, we can use the close() method to close the resources. But if you forget to close the resource, it will lead ... Read More

A String is a class in Java which stores a sequence of characters, it belongs to the java.lang package. Once you create a String object you cannot modify them (immutable).StorageAll String objects are stored in a separate memory location in the heap area known as, String Constant pool.Whenever you define a String value JVM creates a String object with the given value in the String constant pool. Therefore, if you run the above program two String values are created in the String constant pool.The intern() methodThis method returns value of the current String from the pool of unique String values. ... Read More

While a superclass method throws an exception when overriding it, you need to follow certain rules. We will be discussing these rules in this chapter. What is Exception Handling in Java? Exception handling is a mechanism to handle errors in the program. For example, if a program tries to divide a number by zero, it will throw an ArithmeticException. In such cases, the program will terminate abnormally. To avoid this, we can use exception handling. Now, let's discuss the rules of exception handling with respect to method overriding. Those are: Should throw the same exception or a subtype ... Read More