FilterReader - JRE Emulation | JRE Emulation
public abstract class

FilterReader

extends Reader
java.lang.Object
   ↳ java.io.Reader
     ↳ java.io.FilterReader
Known Direct Subclasses

Class Overview

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

Fields
protected Reader in The underlying character-input stream.
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Inherited Fields
From class java.io.Reader
Protected Constructors
FilterReader(Reader in)
Creates a new filtered reader.
Public Methods
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 Methods
[Expand]
From class java.io.Reader
From class java.lang.Object
From interface java.lang.Readable
From interface java.io.Closeable
From interface java.lang.AutoCloseable

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