1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
   1. Methods declared in class OutputStream
   2. Methods declared in class Object
5. Field Details
   1. buf
   2. count
6. Constructor Details
   1. ByteArrayOutputStream()
   2. ByteArrayOutputStream(int)
7. Method Details
   1. write(int)
   2. write(byte[], int, int)
   3. writeBytes(byte[])
   4. writeTo(OutputStream)
   5. reset()
   6. toByteArray()
   7. size()
   8. toString()
   9. toString(String)
   10. toString(Charset)
   11. toString(int)
   12. close()

• Field Summary

  Fields
  Modifier and Type

  Field

  Description

  protected byte[]

  buf

  The buffer where data is stored.

  protected int

  count

  The number of valid bytes in the buffer.

• Constructor Summary

  Constructors
  Constructor

  Description

  ByteArrayOutputStream()

  Creates a new ByteArrayOutputStream.

  ByteArrayOutputStream(int size)

  Creates a new ByteArrayOutputStream, with a buffer capacity of the specified size, in bytes.

• Method Summary

  All MethodsInstance MethodsConcrete MethodsDeprecated Methods

  Modifier and Type

  Method

  Description

  void

  close()

  Closing a ByteArrayOutputStream has no effect.

  void

  reset()

  Resets the count field of this ByteArrayOutputStream 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 default charset.

  String

  toString(int hibyte)

  Deprecated.

  This method does not properly convert bytes into characters.

  String

  toString(String charsetName)

  Converts the buffer's contents into a string by decoding the bytes using the named charset.

  String

  toString(Charset charset)

  Converts the buffer's contents into a string by decoding the bytes using the specified charset.

  void

  write(byte[] b, int off, int len)

  Writes len bytes from the specified byte array starting at offset off to this ByteArrayOutputStream.

  void

  write(int b)

  Writes the specified byte to this ByteArrayOutputStream.

  void

  writeBytes(byte[] b)

  Writes the complete contents of the specified byte array to this ByteArrayOutputStream.

  void

  writeTo(OutputStream out)

  Writes the complete contents of this ByteArrayOutputStream to the specified output stream argument, as if by calling the output stream's write method using out.write(buf, 0, count).

  Methods declared in class OutputStream

  flush, nullOutputStream, write

  Modifier and Type

  Method

  Description

  void

  flush()

  Flushes this output stream and forces any buffered output bytes to be written out.

  static OutputStream

  nullOutputStream()

  Returns a new OutputStream which discards all bytes.

  void

  write(byte[] b)

  Writes b.length bytes from the specified byte array to this output stream.

  Methods declared in class Object

  clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

  Modifier and Type

  Method

  Description

  protected Object

  clone()

  Creates and returns a copy of this object.

  boolean

  equals(Object obj)

  Indicates whether some other object is "equal to" this one.

  protected void

  finalize()

  Deprecated, for removal: This API element is subject to removal in a future version.

  Finalization is deprecated and subject to removal in a future release.

  final Class<?>

  getClass()

  Returns the runtime class of this Object.

  int

  hashCode()

  Returns a hash code value for this object.

  final void

  notify()

  Wakes up a single thread that is waiting on this object's monitor.

  final void

  notifyAll()

  Wakes up all threads that are waiting on this object's monitor.

  final void

  wait()

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

  final void

  wait(long timeoutMillis)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  final void

  wait(long timeoutMillis, int nanos)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

• Field Details

  • buf

    protected byte[] buf

    The buffer where data is stored.

  • count

    protected int count

    The number of valid bytes in the buffer.

• Constructor Details

  • ByteArrayOutputStream

    public ByteArrayOutputStream()

    Creates a new ByteArrayOutputStream. The buffer capacity is initially 32 bytes, though its size increases if necessary.

  • ByteArrayOutputStream

    public ByteArrayOutputStream(int size)

    Creates a new ByteArrayOutputStream, with a buffer capacity of the specified size, in bytes.

    Parameters: size - the initial size. Throws: IllegalArgumentException - if size is negative.

• Method Details

  • write

    public void write(int b)

    Writes the specified byte to this ByteArrayOutputStream.

    Specified by: write in class OutputStream Parameters: b - the byte to be written.

  • write

    public void write(byte[] b, int off, int len)

    Writes len bytes from the specified byte array starting at offset off to this ByteArrayOutputStream.

    Overrides: write in class OutputStream Parameters: b - the data. off - the start offset in the data. len - the number of bytes to write. Throws: NullPointerException - if b is null. IndexOutOfBoundsException - if off is negative, len is negative, or len is greater than b.length - off

  • writeBytes

    public void writeBytes(byte[] b)

    Writes the complete contents of the specified byte array to this ByteArrayOutputStream.

    API Note: This method is equivalent to write(b, 0, b.length). Parameters: b - the data. Throws: NullPointerException - if b is null. Since: 11

  • writeTo

    public void writeTo(OutputStream out) throws IOException

    Writes the complete contents of this ByteArrayOutputStream to the specified output stream argument, as if by calling the output stream's write method using out.write(buf, 0, count).

    Parameters: out - the output stream to which to write the data. Throws: NullPointerException - if out is null. IOException - if an I/O error occurs.

  • reset

    public void reset()

    Resets the count field of this ByteArrayOutputStream to zero, so that all currently accumulated output in the output stream is discarded. The output stream can be used again, reusing the already allocated buffer space.

    See Also:

    • ByteArrayInputStream.count

  • toByteArray

    public byte[] toByteArray()

    Creates a newly allocated byte array. Its size is the current size of this output stream and the valid contents of the buffer have been copied into it.

    Returns: the current contents of this output stream, as a byte array. See Also:

    • size()

  • size

    public int size()

    Returns the current size of the buffer.

    Returns: the value of the count field, which is the number of valid bytes in this output stream. See Also:

    • count

  • toString

    public String toString()

    Converts the buffer's contents into a string decoding bytes using the default charset. The length of the new String is a function of the charset, and hence may not be equal to the size of the buffer.

    This method always replaces malformed-input and unmappable-character sequences with the default replacement string for the default charset. The CharsetDecoder class should be used when more control over the decoding process is required.

    Overrides: toString in class Object Returns: String decoded from the buffer's contents. Since: 1.1 See Also:

    • Charset.defaultCharset()

  • toString

    public String toString(String charsetName) throws UnsupportedEncodingException

    Converts the buffer's contents into a string by decoding the bytes using the named charset.

    This method is equivalent to #toString(charset) that takes a charset.

    An invocation of this method of the form

    Copy ByteArrayOutputStream b; b.toString("UTF-8")

    behaves in exactly the same way as the expression

    Copy ByteArrayOutputStream b; b.toString(StandardCharsets.UTF_8)

    Parameters: charsetName - the name of a supported charset Returns: String decoded from the buffer's contents. Throws: UnsupportedEncodingException - If the named charset is not supported Since: 1.1

  • toString

    public String toString(Charset charset)

    Converts the buffer's contents into a string by decoding the bytes using the specified charset. The length of the new String is a function of the charset, and hence may not be equal to the length of the byte array.

    This method always replaces malformed-input and unmappable-character sequences with the charset's default replacement string. The CharsetDecoder class should be used when more control over the decoding process is required.

    Parameters: charset - the charset to be used to decode the bytes Returns: String decoded from the buffer's contents. Since: 10

  • toString

    @Deprecated public String toString(int hibyte)

    Deprecated.

    This method does not properly convert bytes into characters. As of JDK 1.1, the preferred way to do this is via the toString(String charsetName) or toString(Charset charset) method, which takes an encoding-name or charset argument, or the toString() method, which uses the default charset.

    Creates a newly allocated string. Its size is the current size of the output stream and the valid contents of the buffer have been copied into it. Each character c in the resulting string is constructed from the corresponding element b in the byte array such that:

    Copy c == (char)(((hibyte & 0xff) << 8) | (b & 0xff))

    Parameters: hibyte - the high byte of each resulting Unicode character. Returns: the current contents of the output stream, as a string. See Also:

    • size()
    • toString(String)
    • toString()
    • Charset.defaultCharset()

  • close

    public void close() throws IOException

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

    Specified by: close in interface AutoCloseable Specified by: close in interface Closeable Overrides: close in class OutputStream Throws: IOException - if an I/O error occurs.

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