ByteArrayOutputStream 

Introduction

The Java.io.ByteArrayOutputStream class implements an output stream in which the data is written into a byte array. The buffer automatically grows as data is written to it.Following are the important points about ByteArrayOutputStream −

• Closing a ByteArrayOutputStream has no effect.
• The methods in this class can be called after the stream has been closed without generating an IOException.

Class declaration

Following is the declaration for Java.io.ByteArrayOutputStream class −

public class ByteArrayOutputStream
   extends OutputStream

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Field

Following are the fields for Java.io.ByteArrayOutputStream class −

• protected byte[] buf − This is the buffer where data is stored.
• protected int count − This is the number of valid bytes in the buffer.

Class constructors

Sr.No.	Constructor & Description
1	ByteArrayOutputStream()This creates a new byte array output stream.
2	ByteArrayOutputStream(int size)This creates a new byte array output stream, with a buffer capacity of the specified size, in bytes.

Class methods

Sr.No.	Method & Description
1	void close()Closing a ByteArrayOutputStream has no effect.
2	void reset()This method resets the count field of this byte array output stream to zero, so that all currently accumulated output in the output stream is discarded.
3	int size()This method returns the current size of the buffer.
4	byte[] toByteArray()This method creates a newly allocated byte array.
5	String toString()This method converts the buffer’s contents into a string decoding bytes using the platform’s default character set.
6	String toString(String charsetName)This method converts the buffer’s contents into a string by decoding the bytes using the specified charsetName.
7	void write(byte[] b, int off, int len)This method writes len bytes from the specified byte array starting at offset off to this byte array output stream.
8	void write(int b)This method Writes the specified byte to this byte array output stream.
9	void writeTo(OutputStream out)This method writes the complete contents of this byte array output stream to the specified output stream argument, as if by calling the output stream’s write method using out.write(buf, 0, count).

Methods inherited

This class inherits methods from the following classes −

• Java.io.OutputStream
• Java.io.Object