Added in API level 1

Writer

abstract class Writer : Appendable, Closeable, Flushable
kotlin.Any
   ↳ java.io.Writer

Abstract class for writing to character streams. The only methods that a subclass must implement are write(char[], int, int), flush(), and close(). Most subclasses, however, will override some of the methods defined here in order to provide higher efficiency, additional functionality, or both.

Summary

Protected constructors

Creates a new character-stream writer whose critical sections will synchronize on the writer itself.

Writer(lock: Any!)

Creates a new character-stream writer whose critical sections will synchronize on the given object.

Public methods
open Writer

Appends the specified character sequence to this writer.

open Writer
append(csq: CharSequence?, start: Int, end: Int)

Appends a subsequence of the specified character sequence to this writer.

open Writer

Appends the specified character to this writer.

abstract Unit

Closes the stream, flushing it first.

abstract Unit

Flushes the stream.

open static Writer!

Returns a new Writer which discards all characters.

open Unit
write(c: Int)

Writes a single character.

open Unit
write(cbuf: CharArray!)

Writes an array of characters.

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

Writes a portion of an array of characters.

open Unit
write(str: String!)

Writes a string.

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

Writes a portion of a string.

Properties
Any!

The object used to synchronize operations on this stream.

Protected constructors

Writer

Added in API level 1
protected Writer()

Creates a new character-stream writer whose critical sections will synchronize on the writer itself.

Writer

Added in API level 1
protected Writer(lock: Any!)

Creates a new character-stream writer whose critical sections will synchronize on the given object.

Parameters
lock Any!: Object to synchronize on

Public methods

append

Added in API level 1
open fun append(csq: CharSequence?): Writer

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.

Parameters
csq CharSequence?: The character sequence to append. If csq is null, then the four characters "null" are appended to this writer.
Return
Writer This writer
Exceptions
java.io.IOException If an I/O error occurs

append

Added in API level 1
open fun append(
    csq: CharSequence?,
    start: Int,
    end: Int
): Writer

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>
Parameters
csq CharSequence?: The character sequence from which a subsequence will be appended. If csq is null, then characters will be appended as if csq contained the four characters "null".
start Int: The index of the first character in the subsequence
end Int: The index of the character following the last character in the subsequence
Return
Writer This writer
Exceptions
java.lang.IndexOutOfBoundsException If start or end are negative, start is greater than end, or end is greater than csq.length()
java.io.IOException If an I/O error occurs

append

Added in API level 1
open fun append(c: Char): Writer

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) 
Parameters
c Char: The 16-bit character to append
Return
Writer This writer
Exceptions
java.io.IOException If an I/O error occurs

close

Added in API level 1
abstract fun close(): Unit

Closes the stream, flushing it first. Once the stream has been closed, further write() or flush() invocations will cause an IOException to be thrown. Closing a previously closed stream has no effect.

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
abstract fun flush(): Unit

Flushes the stream. If the stream has saved any characters from the various write() methods in a buffer, write them immediately to their intended destination. Then, if that destination is another character or byte stream, flush it. Thus one flush() invocation will flush all the buffers in a chain of Writers and OutputStreams.

If the intended destination of this stream is an abstraction provided by the underlying operating system, for example a file, then flushing the stream guarantees only that bytes previously written to the stream are passed to the operating system for writing; it does not guarantee that they are actually written to a physical device such as a disk drive.

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

nullWriter

Added in API level 33
open static fun nullWriter(): Writer!

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.

Return
Writer! a Writer which discards all characters

write

Added in API level 1
open fun write(c: Int): Unit

Writes a single character. The character to be written is contained in the 16 low-order bits of the given integer value; the 16 high-order bits are ignored.

Subclasses that intend to support efficient single-character output should override this method.

Parameters
c Int: int specifying a character to be written
Exceptions
java.io.IOException If an I/O error occurs

write

Added in API level 1
open fun write(cbuf: CharArray!): Unit

Writes an array of characters.

Parameters
cbuf CharArray!: Array of characters to be written
Exceptions
java.io.IOException If an I/O error occurs

write

Added in API level 1
abstract fun write(
    cbuf: CharArray!,
    off: Int,
    len: Int
): Unit

Writes a portion of an array of characters.

Parameters
cbuf CharArray!: Array of characters
off Int: Offset from which to start writing characters
len Int: Number of characters to write
Exceptions
java.lang.IndexOutOfBoundsException Implementations should throw this exception 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(str: String!): Unit

Writes a string.

Parameters
str String!: String to be written
Exceptions
java.io.IOException If an I/O error occurs

write

Added in API level 1
open fun write(
    str: String!,
    off: Int,
    len: Int
): Unit

Writes a portion of a string.

Parameters
str String!: A String
off Int: Offset from which to start writing characters
len Int: Number of characters to write
Exceptions
java.lang.IndexOutOfBoundsException Implementations should throw this exception if off is negative, or len is negative, or off + len is negative or greater than the length of the given string
java.io.IOException If an I/O error occurs

Properties

lock

Added in API level 1
protected var lock: Any!

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.