ByteArrayOutputStream class « ByteArrayOutputStream « Stream for Output « File Stream

This class implements an output stream in which the data is written into a byte array.

Constructor	Summary
ByteArrayOutputStream()	Creates a new byte array output stream.
ByteArrayOutputStream(int size)	Creates a new byte array output stream, with a buffer capacity of the specified size, in bytes.

Return	Method	Summary
void	close()	Closing a ByteArrayOutputStream has no effect.
void	reset()	Resets the count field of this byte array output stream to zero, so that all currently accumulated output in the output stream is discarded.
int	size()	Returns the current size of the buffer.
byte[]	toByteArray()	Creates a newly allocated byte array.
String	toString()	Converts the buffer's contents into a string decoding bytes using the platform's default character set.
String	toString(String charsetName)	Converts the buffer's contents into a string by decoding the bytes using the specified charsetName.
void	write(byte[] b, int off, int len)	Writes len bytes from the specified byte array starting at offset off to this byte array output stream.
void	write(int b)	Writes the specified byte to this byte array output stream.
void	writeTo(OutputStream out)	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).


import java.io.ByteArrayOutputStream;
import java.io.IOException;

public class Main {
  public static void main(String args[]) throws IOException {
    ByteArrayOutputStream outStream = new ByteArrayOutputStream();
    outStream.write('a');
    outStream.write(("java2s.com").getBytes());
    System.out.println("outstream: " + outStream);
    System.out.println("size: " + outStream.size());
    outStream.close();
  }
}


outstream: ajava2s.com
size: 11


import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Arrays;

public class Main {
  public static void main(String args[]) throws IOException {
    ByteArrayOutputStream outStream = new ByteArrayOutputStream();
    outStream.write('a');
    outStream.write(("java2s.com").getBytes());
   
    System.out.println(Arrays.toString(outStream.toByteArray()));
    System.out.println(new String(outStream.toByteArray()));
    outStream.close();
  }
}


[97, 106, 97, 118, 97, 50, 115, 46, 99, 111, 109]
ajava2s.com