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java.io
public class: BufferedWriter [javadoc | source]
java.lang.Object
   java.io.Writer
      java.io.BufferedWriter

All Implemented Interfaces:
    Flushable, Closeable, Appendable

Writes 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.
Fields inherited from java.io.Writer:
lock
Constructor:
 public BufferedWriter(Writer out) 
    Creates a buffered character-output stream that uses a default-sized output buffer.
    Parameters:
    out - A Writer
 public BufferedWriter(Writer out,
    int sz) 
    Creates 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
    exception: IllegalArgumentException - If sz is <= 0
Method from java.io.BufferedWriter Summary:
close,   flush,   flushBuffer,   newLine,   write,   write,   write
Methods from java.io.Writer:
append,   append,   append,   close,   flush,   write,   write,   write,   write,   write
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from java.io.BufferedWriter Detail:
 public  void close() throws IOException 
 public  void flush() throws IOException 
    Flushes the stream.
  void flushBuffer() throws IOException 
    Flushes the output buffer to the underlying character stream, without flushing the stream itself. This method is non-private only so that it may be invoked by PrintStream.
 public  void newLine() throws IOException 
    Writes a line separator. The line separator string is defined by the system property line.separator, and is not necessarily a single newline ('\n') character.
 public  void write(int c) throws IOException 
    Writes a single character.
 public  void write(char[] cbuf,
    int off,
    int len) throws IOException 
    Writes 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.

 public  void write(String s,
    int off,
    int len) throws IOException 
    Writes a portion of a String.

    If the value of the len parameter is negative then no characters are written. This is contrary to the specification of this method in the {@linkplain java.io.Writer#write(java.lang.String,int,int) superclass}, which requires that an IndexOutOfBoundsException be thrown.