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