Added in API level 1

FilterReader

abstract class FilterReader : Reader

kotlin.Any
↳	java.io.Reader
	↳	java.io.FilterReader

Known Direct Subclasses PushbackReader PushbackReader A character-stream reader that allows characters to be pushed back into the stream.

Abstract class for reading filtered character streams. The abstract class FilterReader itself provides default methods that pass all requests to the contained stream. Subclasses of FilterReader should override some of these methods and may also provide additional methods and fields.

Summary

Protected constructors
FilterReader(in: Reader!) Creates a new filtered reader.

Public methods
open Unit	close()
open Unit	mark(readAheadLimit: Int) Marks the present position in the stream.
open Boolean	markSupported() Tells whether this stream supports the mark() operation.
open Int	read() Reads a single character.
open Int	read(cbuf: CharArray!, off: Int, len: Int) Reads characters into a portion of an array.
open Boolean	ready() Tells whether this stream is ready to be read.
open Unit	reset() Resets the stream.
open Long	skip(n: Long) Skips characters.

Inherited functions

From class Reader Reader! nullReader() Returns a new Reader that reads no 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 read(), read(char[]), read(char[], int, int), read(Charbuffer), ready(), skip(long), and transferTo() methods all behave as if end of stream has been reached. After the stream has been closed, these methods all throw IOException. The markSupported() method returns false. The mark() and reset() methods throw an IOException. The object used to synchronize operations on the returned Reader is not specified. Int read(cbuf: CharArray!) Reads characters into an array. This method will block until some input is available, an I/O error occurs, or the end of the stream is reached. Int read(target: CharBuffer!) Attempts to read characters into the specified character buffer. The buffer is used as a repository of characters as-is: the only changes made are the results of a put operation. No flipping or rewinding of the buffer is performed. Long transferTo(out: Writer!) Reads all characters from this reader and writes the characters to the given writer in the order that they are read. On return, this reader will be at end of the stream. This method does not close either reader or writer. This method may block indefinitely reading from the reader, or writing to the writer. The behavior for the case where the reader and/or writer is asynchronously closed, or the thread interrupted during the transfer, is highly reader and writer specific, and therefore not specified. If an I/O error occurs reading from the reader or writing to the writer, then it may do so after some characters have been read or written. Consequently the reader may not be at end of the stream and one, or both, streams may be in an inconsistent state. It is strongly recommended that both streams be promptly closed if an I/O error occurs.

Properties
Reader!	in The underlying character-input stream.

Inherited properties
From class Reader 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.

Protected constructors

FilterReader

Added in API level 1

protected FilterReader(in: Reader!)

Creates a new filtered reader.

Parameters
in	Reader!: a Reader object providing the underlying stream.

Exceptions
java.lang.NullPointerException	if in is null

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

mark

Added in API level 1

open fun mark(readAheadLimit: Int): Unit

Marks the present position in the stream.

Parameters
readAheadLimit	Int: Limit on the number of characters that may be read while still preserving the mark. After reading this many characters, attempting to reset the stream may fail.

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

markSupported

Added in API level 1

open fun markSupported(): Boolean

Tells whether this stream supports the mark() operation.

Return
Boolean	true if and only if this stream supports the mark operation.

read

Added in API level 1

open fun read(): Int

Reads a single character.

Return
Int	The character read, as an integer in the range 0 to 65535 (0x00-0xffff), or -1 if the end of the stream has been reached

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

read

Added in API level 1

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

Reads characters into a portion of an array.

Parameters
cbuf	CharArray!: Destination buffer
off	Int: Offset at which to start storing characters
len	Int: Maximum number of characters to read

Return
Int	The number of characters read, or -1 if the end of the stream has been reached

Exceptions
java.io.IOException	If an I/O error occurs
java.lang.IndexOutOfBoundsException	If off is negative, or len is negative, or len is greater than cbuf.length - off

ready

Added in API level 1

open fun ready(): Boolean

Tells whether this stream is ready to be read.

Return
Boolean	True if the next read() is guaranteed not to block for input, false otherwise. Note that returning false does not guarantee that the next read will block.

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

reset

Added in API level 1

open fun reset(): Unit

Resets the stream.

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

skip

Added in API level 1

open fun skip(n: Long): Long

Skips characters.

Parameters
n	Long: The number of characters to skip

Return
Long	The number of characters actually skipped

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

Properties

in

Added in API level 1

protected var in: Reader!

The underlying character-input stream.