public class ByteArrayOutputStream extends OutputStream
toByteArray() and
 toString().
 Closing a ByteArrayOutputStream has no effect. The methods in this class can be called after the stream has been closed without generating an IOException.
| Modifier and Type | Field and Description | 
|---|---|
| protected byte[] | bufThe buffer where data is stored. | 
| protected int | countThe number of valid bytes in the buffer. | 
| Constructor and Description | 
|---|
| 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. | 
| Modifier and Type | Method and Description | 
|---|---|
| void | close()Closing a ByteArrayOutputStream has no effect. | 
| void | reset()Resets the  countfield 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(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 enc)method, which takes an encoding-name
 argument, or thetoString()method, which uses the
 platform's default character encoding. | 
| String | toString(String charsetName)Converts the buffer's contents into a string by decoding the bytes using
 the named  charset. | 
| void | write(byte[] b,
     int off,
     int len)Writes  lenbytes from the specified byte array
 starting at offsetoffto 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). | 
flush, writeprotected byte[] buf
protected int count
public ByteArrayOutputStream()
public ByteArrayOutputStream(int size)
size - the initial size.IllegalArgumentException - if size is negative.public void write(int b)
write in class OutputStreamb - the byte to be written.public void write(byte[] b,
                  int off,
                  int len)
len bytes from the specified byte array
 starting at offset off to this byte array output stream.write in class OutputStreamb - the data.off - the start offset in the data.len - the number of bytes to write.public void writeTo(OutputStream out) throws IOException
out.write(buf, 0, count).out - the output stream to which to write the data.IOException - if an I/O error occurs.public void reset()
count field of this byte array output
 stream 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.ByteArrayInputStream.countpublic byte[] toByteArray()
size()public int size()
count field, which is the number
          of valid bytes in this output stream.countpublic String toString()
This method always replaces malformed-input and unmappable-character sequences with the default replacement string for the platform's default character set. The CharsetDecoder class should be used when more control over the decoding process is required.
public String toString(String charsetName) throws UnsupportedEncodingException
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 this charset's default replacement string. The CharsetDecoder class should be used when more control
 over the decoding process is required.
charsetName - the name of a supported
             charsetUnsupportedEncodingException - If the named charset is not supported@Deprecated public String toString(int hibyte)
toString(String enc) method, which takes an encoding-name
 argument, or the toString() method, which uses the
 platform's default character encoding.
     c == (char)(((hibyte & 0xff) << 8) | (b & 0xff))
 hibyte - the high byte of each resulting Unicode character.size(), 
toString(String), 
toString()public void close()
           throws IOException
close in interface Closeableclose in interface AutoCloseableclose in class OutputStreamIOException - if an I/O error occurs. Submit a bug or feature 
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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