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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

Constructor Index

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

Method Index

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

Constructors

o BufferedWriter 
 public BufferedWriter(Writer out)
Create a buffered character-output stream that uses a default-sized output buffer.

Parameters:
out - A Writer
o 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

Methods

o 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
o 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 BufferedWriters 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
o 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
o 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
o flush 
 public void flush() throws IOException
Flush the stream.

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