Added in API level 1

BufferedWriter

open class BufferedWriter : Writer

kotlin.Any
↳	java.io.Writer
	↳	java.io.BufferedWriter

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.

Summary

Public constructors
BufferedWriter(out: Writer!) Creates a buffered character-output stream that uses a default-sized output buffer.
BufferedWriter(out: Writer!, sz: Int) Creates a new buffered character-output stream that uses an output buffer of the given size.

Public methods
open Unit	close()
open Unit	flush() Flushes the stream.
open Unit	newLine() Writes a line separator.
open Unit	write(cbuf: CharArray!, off: Int, len: Int) Writes a portion of an array of characters.
open Unit	write(c: Int) Writes a single character.
open Unit	write(s: String!, off: Int, len: Int) Writes a portion of a String.

Inherited functions

From class Writer Writer append(c: Char) Appends the specified character to this writer. An invocation of this method of the form out.append(c) behaves in exactly the same way as the invocation out.write(c) Writer append(csq: CharSequence?) Appends the specified character sequence to this writer. An invocation of this method of the form out.append(csq) behaves in exactly the same way as the invocation out.write(csq.toString()) Depending on the specification of toString for the character sequence csq, the entire sequence may not be appended. For instance, invoking the toString method of a character buffer will return a subsequence whose content depends upon the buffer's position and limit. Writer append(csq: CharSequence?, start: Int, end: Int) Appends a subsequence of the specified character sequence to this writer. Appendable. An invocation of this method of the form out.append(csq, start, end) when csq is not null behaves in exactly the same way as the invocation <code>out.write(csq.subSequence(start, end).toString()) </code> Writer! nullWriter() Returns a new Writer which discards all characters. The returned stream is initially open. The stream is closed by calling the close() method. Subsequent calls to close() have no effect. While the stream is open, the append(char), append(CharSequence), append(CharSequence, int, int), flush(), write(int), write(char[]), and write(char[], int, int) methods do nothing. After the stream has been closed, these methods all throw IOException. The object used to synchronize operations on the returned Writer is not specified. Unit write(cbuf: CharArray!) Writes an array of characters. Unit write(str: String!) Writes a string.

Inherited properties
From class Writer Any! lock The object used to synchronize operations on this stream. For efficiency, a character-stream object may use an object other than itself to protect critical sections. A subclass should therefore use the object in this field rather than this or a synchronized method.

Public constructors

BufferedWriter

Added in API level 1

BufferedWriter(out: Writer!)

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

Parameters
out	Writer!: A Writer

BufferedWriter

Added in API level 1

BufferedWriter(
    out: Writer!, 
    sz: Int)

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

Parameters
out	Writer!: A Writer
sz	Int: Output-buffer size, a positive integer

Exceptions
java.lang.IllegalArgumentException	If sz <= 0

Public methods

close

Added in API level 1

open fun close(): Unit

Exceptions
java.lang.Exception	if this resource cannot be closed
java.io.IOException	If an I/O error occurs

flush

Added in API level 1

open fun flush(): Unit

Flushes the stream.

Exceptions
java.io.IOException	If an I/O error occurs
java.io.IOException	If an I/O error occurs

newLine

Added in API level 1

open fun newLine(): Unit

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.

Exceptions
java.io.IOException	If an I/O error occurs

write

Added in API level 1

open fun write(
    cbuf: CharArray!, 
    off: Int, 
    len: Int
): Unit

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.

Parameters
cbuf	CharArray!: A character array
off	Int: Offset from which to start reading characters
len	Int: Number of characters to write

Exceptions
java.lang.IndexOutOfBoundsException	If off is negative, or len is negative, or off + len is negative or greater than the length of the given array
java.io.IOException	If an I/O error occurs

write

Added in API level 1

open fun write(c: Int): Unit

Writes a single character.

Parameters
c	Int: int specifying a character to be written

Exceptions
java.io.IOException	If an I/O error occurs
java.io.IOException	If an I/O error occurs

write

Added in API level 1

open fun write(
    s: String!, 
    off: Int, 
    len: Int
): Unit

Writes a portion of a String.

Parameters
str	A String
off	Int: Offset from which to start reading characters
len	Int: Number of characters to be written
s	String!: String to be written

Exceptions
java.lang.IndexOutOfBoundsException	If off is negative, or off + len is greater than the length of the given string
java.io.IOException	If an I/O error occurs