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# Class java.io.BufferedWriter

    java.lang.Object
       |
       +----java.io.Writer
               |
               +----java.io.BufferedWriter

public class BufferedWriter
extends Writer

Write text to a character-output stream, buffering characters so as to provide for the efficient writing of single characters, arrays, and strings.

The buffer size may be specified, or the default size may be accepted. The default is large enough for most purposes.

A newLine() method is provided, which uses the platform's own notion of line separator as defined by the system property `line.separator`. Not all platforms use the newline character ('\n') to terminate lines. Calling this method to terminate each output line is therefore preferred to writing a newline character directly.

In general, a Writer sends its output immediately to the underlying character or byte stream. Unless prompt output is required, it is advisable to wrap a BufferedWriter around any Writer whose write() operations may be costly, such as FileWriters and OutputStreamWriters. For example,

     PrintWriter out
       = new PrintWriter(new BufferedWriter(new FileWriter("foo.out")));

will buffer the PrintWriter's output to the file. Without buffering, each invocation of a print() method would cause characters to be converted into bytes that would then be written immediately to the file, which can be very inefficient.

See Also:
  PrintWriter, FileWriter, OutputStreamWriter

##

BufferedWriter(Writer)
  Create a buffered character-output stream that uses a default-sized output buffer.
BufferedWriter(Writer, int)
  Create a new buffered character-output stream that uses an output buffer of the given size.

##

close()
  Close the stream.
flush()
  Flush the stream.
newLine()
  Write a line separator.
write(char[], int, int)
  Write a portion of an array of characters.
write(int)
  Write a single character.
write(String, int, int)
  Write a portion of a String.

##

BufferedWriter

     public BufferedWriter(Writer out)

  Create a buffered character-output stream that uses a default-sized output buffer.

  Parameters:
    out - A Writer

BufferedWriter

     public BufferedWriter(Writer out,
                           int sz)

  Create a new buffered character-output stream that uses an output buffer of the given size.

  Parameters:
    out - A Writer
    sz - Output-buffer size, a positive integer
  Throws: IllegalArgumentException
    If sz is <= 0

##

write

     public void write(int c) throws IOException

  Write a single character.

  Throws: IOException
    If an I/O error occurs
  Overrides:
    write in class Writer

write

     public void write(char cbuf[],
                       int off,
                       int len) throws IOException

  Write a portion of an array of characters.

  Ordinarily this method stores characters from the given array into this stream's buffer, flushing the buffer to the underlying stream as needed. If the requested length is at least as large as the buffer, however, then this method will flush the buffer and write the characters directly to the underlying stream. Thus redundant `BufferedWriter`s will not copy data unnecessarily.

  Parameters:
    cbuf - A character array
    off - Offset from which to start reading characters
    len - Number of characters to write
  Throws: IOException
    If an I/O error occurs
  Overrides:
    write in class Writer

write

     public void write(String s,
                       int off,
                       int len) throws IOException

  Write a portion of a String.

  Parameters:
    s - String to be written
    off - Offset from which to start reading characters
    len - Number of characters to be written
  Throws: IOException
    If an I/O error occurs
  Overrides:
    write in class Writer

newLine

     public void newLine() throws IOException

  Write a line separator. The line separator string is defined by the system property `line.separator`, and is not necessarily a single newline ('\n') character.

  Throws: IOException
    If an I/O error occurs

flush

     public void flush() throws IOException

  Flush the stream.

  Throws: IOException
    If an I/O error occurs
  Overrides:
    flush in class Writer

close

     public void close() throws IOException

  Close the stream.

  Throws: IOException
    If an I/O error occurs
  Overrides:
    close in class Writer

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