FilterReader

public abstract class FilterReader extends Reader

Known Direct Subclasses

PushbackReader

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.

Field Summary

protected Reader in The underlying character-input stream.

Inherited Field Summary

From class java.io.Reader

protected Object lock The object used to synchronize operations on this stream.

Protected Constructor Summary

FilterReader(Reader in)

Creates a new filtered reader.

Public Method Summary

void	close() Closes the stream and releases any system resources associated with it.
void	mark(int readAheadLimit) Marks the present position in the stream.
boolean	markSupported() Tells whether this stream supports the mark() operation.
int	read() Reads a single character.
int	read(char[] cbuf, int off, int len) Reads characters into a portion of an array.
boolean	ready() Tells whether this stream is ready to be read.
void	reset() Resets the stream.
long	skip(long n) Skips characters.

Inherited Method Summary

From class java.io.Reader

abstract void	close() Closes the stream and releases any system resources associated with it.
void	mark(int readAheadLimit) Marks the present position in the stream.
boolean	markSupported() Tells whether this stream supports the mark() operation.
int	read() Reads a single character.
abstract int	read(char[] cbuf, int off, int len) Reads characters into a portion of an array.
int	read(char[] cbuf) Reads characters into an array.
int	read(CharBuffer target) Attempts to read characters into the specified character buffer.
boolean	ready() Tells whether this stream is ready to be read.
void	reset() Resets the stream.
long	skip(long n) Skips characters.

From class java.lang.Object

Object	clone() Creates and returns a copy of this `Object`.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of `Class` that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.

From interface java.lang.Readable

abstract int

read(CharBuffer cb)

Attempts to read characters into the specified character buffer.

From interface java.io.Closeable

abstract void

close()

Closes this stream and releases any system resources associated with it.

From interface java.lang.AutoCloseable

abstract void

close()

Closes this resource, relinquishing any underlying resources.

Fields

protected Reader in

The underlying character-input stream.

Protected Constructors

protected FilterReader (Reader in)

Creates a new filtered reader.

Parameters

in	a Reader object providing the underlying stream.

Throws

NullPointerException	if `in` is `null`

Public Methods

public void close ()

Closes the stream and releases any system resources associated with it. Once the stream has been closed, further read(), ready(), mark(), reset(), or skip() invocations will throw an IOException. Closing a previously closed stream has no effect.

Throws

IOException

public void mark (int readAheadLimit)

Marks the present position in the stream.

Parameters

readAheadLimit	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.

Throws

IOException	If an I/O error occurs

public boolean markSupported ()

Tells whether this stream supports the mark() operation.

Returns

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

public int read ()

Reads a single character.

Returns

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

Throws

IOException	If an I/O error occurs

public int read (char[] cbuf, int off, int len)

Reads characters into a portion of an array.

Parameters

cbuf	Destination buffer
off	Offset at which to start storing characters
len	Maximum number of characters to read

Returns

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

Throws

IOException	If an I/O error occurs

public boolean ready ()

Tells whether this stream is ready to be read.

Returns

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.

Throws

IOException	If an I/O error occurs

public void reset ()

Resets the stream.

Throws

IOException	If an I/O error occurs

public long skip (long n)

Skips characters.

Parameters

n	The number of characters to skip

Returns

The number of characters actually skipped

Throws

IOException	If an I/O error occurs