java.nio.charset.Charset Class in Java

In Java, Charset is a mapping technique used in Java to map the 16-bit Unicode sequence and sequences of bytes. It is also used to encode and decode the string data text into different character encoding. It comes under java.nio.charset.Charset package.

The charset must begin with a number or letter. Every charset can decode and encode. For constructing a map that contains every charset, support is available in JVM(Java Virtual Machine).

Methods of Charset

Method	Description
newDecoder()	Creates a new decoder
newEncoder()	Creates a new encoder
getName()	Returns the canonical name
aliases()	Returns an array of aliases
isSupported()	Tests whether this charset is supported by the current Java virtual machine

Classes of Charset

Class	Description
Charset	this is a named mapping between characters and bytes
CharsetDecoder	this class decodes bytes into characters
CharsetEncoder	this class encodes character into bytes
CoderResult	it is a description of the result state of a coder
CodingErrorAction	it detects coding errors and take error action

Standard charsets

Standard Charsets	Description
US-ASCII	7 bit ASCII characters. Represents the basic English alphabet and some control characters.
ISO-8859-1	ISO Latin Alphabet No. 1 that covers the Latin script and some common symbols.
UTF-8	8-bit UCS Transformation which consists of most of the characters(from different languages).
UTF-16BE	16-bit UCS Transformation Format in this characters are encoded using big-endian byte
UTF-16LE	16-bit UCS Transformation Format in this characters are encoded using little-endian byte order.
UTF-16	16-bit UCS Transformation Format this is often used for internal text processing.

Using a charset Encoding a string into sequence of bytes

Encoded String into a sequence of bytes using the given charset, storing the result into a new byte array.

public byte[] getBytes(Charset charset);

Example:

java.nio.charset.Charset charset = java.nio.charset.Charset.forName("ASCII");
byte[] byteArray = "Hi".getBytes(charset);

Java Charset Example

Java

public class Main
{
    public static void main(String[] args)
    {
        String s= "GFG";

        java.nio.charset.Charset charSet = java.nio.charset.Charset.forName("ASCII");

        byte[] byteArr= s.getBytes(charSet);
        System.out.println("byteArr of \"GFG\" with charsetName \"ASCII\" = " + byteArr);
        for (byte a : byteArr)
        {
            System.out.println(a);
        }

    }
}

Output

byteArr of "GFG" with charsetName "ASCII" = [B@3af49f1c
71
70
71