Java in a Nutshell, 5th Edition [Electronic resources] نسخه متنی

This abstract class
is the superclass of all character input streams. It is an analog to
InputStream, which is the superclass of all byte
input streams. Reader defines the basic methods
that all character output streams provide. read(
) returns a single character or an array
(or subarray) of characters, blocking if necessary; it returns -1 if
the end of the stream has been reached. ready(
) returns true if
there are characters available for reading. If ready(
) returns TRue, the next call to
read( ) is guaranteed not to block.
close( ) closes the
character input stream. skip(
) skips a specified number of characters
in the input stream. If markSupported(
)
returns true,
mark( ) marks a position in the stream and, if
necessary, creates a look-ahead buffer of the specified size. Future
calls to reset( ) restore
the stream to the marked position if they occur within the specified
look-ahead limit. Note that not all stream types support this
mark-and-reset functionality. To create a subclass of
Reader, you need only implement the three-argument
version of read( ) and the close(
) method. Most subclasses implement additional methods,
however.

Figure 9-54. java.io.Reader

public abstract class

Reader implements Closeable, Readable {
// Protected Constructors
protected

Reader ( );
protected

Reader (Object

lock );
// Public Instance Methods
public abstract void

close ( ) throws IOException; Implements:Closeable
public void

mark (int

readAheadLimit ) throws IOException;
public boolean

markSupported ( ); constant
public int

read ( ) throws IOException;
public int

read (char[ ]

cbuf ) throws IOException;
public abstract int

read (char[ ]

cbuf , int

off , int

len ) throws IOException;
public boolean

ready ( ) throws IOException; constant
public void

reset ( ) throws IOException;
public long

skip (long

n ) throws IOException;
// Methods Implementing Closeable
public abstract void

close ( ) throws IOException;
// Methods Implementing Readable

5.0 public int

read (java.nio.CharBuffer

target ) throws IOException;
// Protected Instance Fields
protected Object

lock ;
}

Subclasses

BufferedReader,
CharArrayReader, FilterReader,
InputStreamReader, PipedReader,
StringReader

Passed To

BufferedReader.BufferedReader( ),
FilterReader.FilterReader( ),
LineNumberReader.LineNumberReader( ),
PushbackReader.PushbackReader( ),
StreamTokenizer.StreamTokenizer( ),
javax.xml.transform.stream.StreamSource.{setReader(
), StreamSource( )},
org.xml.sax.InputSource.{InputSource( ),
setCharacterStream( )}

Returned By

java.nio.channels.Channels.newReader( ),
javax.xml.transform.stream.StreamSource.getReader(
), org.xml.sax.InputSource.getCharacterStream(
)

Type Of

FilterReader.in