java.io

Class ByteArrayOutputStream

java.lang.Object

java.io.OutputStream

java.io.ByteArrayOutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

public class ByteArrayOutputStream
extends OutputStream

A specialized OutputStream for class for writing content to an (internal) byte array. As bytes are written to this stream, the byte array may be expanded to hold more bytes. When the writing is considered to be finished, a copy of the byte array can be requested from the class.

See Also:

ByteArrayInputStream

Field Summary

Fields

Modifier and Type	Field and Description
protected byte[]	buf The byte array containing the bytes written.
protected int	count The number of bytes written.

Constructor Summary

Constructors

Constructor and Description
ByteArrayOutputStream() Constructs a new ByteArrayOutputStream with a default size of 32 bytes.
ByteArrayOutputStream(int size) Constructs a new ByteArrayOutputStream with a default size of size bytes.

Method Summary

Modifier and Type	Method and Description
void	close() Closes this stream.
void	reset() Resets this stream to the beginning of the underlying byte array.
int	size() Returns the total number of bytes written to this stream so far.
byte[]	toByteArray() Returns the contents of this ByteArrayOutputStream as a byte array.
String	toString() Returns the contents of this ByteArrayOutputStream as a string.
String	toString(int hibyte) Deprecated. Use toString() instead.
String	toString(String charsetName) Returns the contents of this ByteArrayOutputStream as a string converted according to the encoding declared in charsetName.
void	write(byte[] buffer, int offset, int len) Writes count bytes from the byte array buffer starting at offset index to this stream.
void	write(int oneByte) Writes the specified byte oneByte to the OutputStream.
void	writeTo(OutputStream out) Takes the contents of this stream and writes it to the output stream out.

Methods inherited from class java.io.OutputStream

flush, write

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode

Field Detail

buf

protected byte[] buf

The byte array containing the bytes written.

count

protected int count

The number of bytes written.

Constructor Detail

ByteArrayOutputStream

public ByteArrayOutputStream()

Constructs a new ByteArrayOutputStream with a default size of 32 bytes. If more than 32 bytes are written to this instance, the underlying byte array will expand.

ByteArrayOutputStream

public ByteArrayOutputStream(int size)

Constructs a new ByteArrayOutputStream with a default size of size bytes. If more than size bytes are written to this instance, the underlying byte array will expand.

Parameters:

size - initial size for the underlying byte array, must be non-negative.

Throws:

IllegalArgumentException - if size < 0.

Method Detail

close

public void close()
           throws IOException

Closes this stream. This releases system resources used for this stream.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class OutputStream

Throws:

IOException - if an error occurs while attempting to close this stream.

reset

public void reset()

Resets this stream to the beginning of the underlying byte array. All subsequent writes will overwrite any bytes previously stored in this stream.

size

public int size()

Returns the total number of bytes written to this stream so far.

Returns:

the number of bytes written to this stream.

toByteArray

public byte[] toByteArray()

Returns the contents of this ByteArrayOutputStream as a byte array. Any changes made to the receiver after returning will not be reflected in the byte array returned to the caller.

Returns:

this stream's current contents as a byte array.

toString

public String toString()

Returns the contents of this ByteArrayOutputStream as a string. Any changes made to the receiver after returning will not be reflected in the string returned to the caller.

Overrides:

toString in class Object

Returns:

this stream's current contents as a string.

toString

@Deprecated
public String toString(int hibyte)

Deprecated. Use toString() instead.

Returns the contents of this ByteArrayOutputStream as a string. Each byte b in this stream is converted to a character c using the following function: c == (char)(((hibyte & 0xff) << 8) | (b & 0xff)). This method is deprecated and either toString() or toString(String) should be used.

Parameters:

hibyte - the high byte of each resulting Unicode character.

Returns:

this stream's current contents as a string with the high byte set to hibyte.

toString

public String toString(String charsetName)
                throws UnsupportedEncodingException

Returns the contents of this ByteArrayOutputStream as a string converted according to the encoding declared in charsetName.

Parameters:

charsetName - a string representing the encoding to use when translating this stream to a string.

Returns:

this stream's current contents as an encoded string.

Throws:

UnsupportedEncodingException - if the provided encoding is not supported.

write

public void write(byte[] buffer,
                  int offset,
                  int len)

Writes count bytes from the byte array buffer starting at offset index to this stream.

Overrides:

write in class OutputStream

Parameters:

buffer - the buffer to be written.

offset - the initial position in buffer to retrieve bytes.

len - the number of bytes of buffer to write.

Throws:

NullPointerException - if buffer is null.

IndexOutOfBoundsException - if offset < 0 or len < 0, or if offset + len is greater than the length of buffer.

write

public void write(int oneByte)

Writes the specified byte oneByte to the OutputStream. Only the low order byte of oneByte is written.

Specified by:

write in class OutputStream

Parameters:

oneByte - the byte to be written.

writeTo

public void writeTo(OutputStream out)
             throws IOException

Takes the contents of this stream and writes it to the output stream out.

Parameters:

out - an OutputStream on which to write the contents of this stream.

Throws:

IOException - if an error occurs while writing to out.