oracle.ifs.beans.parsers

Class ParserReader

java.lang.Object

java.io.Reader

oracle.ifs.beans.parsers.ParserReader

All Implemented Interfaces:

Closeable, AutoCloseable, Readable

public class ParserReader
extends Reader

A ParserReader is a Reader that supports buffering of input such that the buffer can be reset to the beginning, allowing characters to be re-read.

As such, a ParserReader can be used whenever the input data needs to be re-read. For example, it is used for pre-parsing a file to determine the nature of its content, before passing it to the appropriate parser for actual parsing.

It can operate in buffering or non-buffering mode. When in buffering mode, it buffers the input, extending the size of the buffer as required.

The ParserReader can be reset to allow re-reading of the input data. When reset and put in non-buffering mode, it consumes the characters in the buffer to service read requests, until it reaches the end of the buffered data, at which point it will start reading from the underlying Reader. When reset and operating in buffering mode, it consumes the characters in the buffer to service read requests, until it reaches the end of the buffered data, at which point it will read more data into the buffer and services read requests from the contents of the buffer.

A ParserReader can only be reset if already in buffering mode.

(Unpublished)

Field Summary

Fields inherited from class java.io.Reader

lock

Constructor Summary

Constructors

Constructor and Description
ParserReader(Reader reader) Constructs a ParserReader from a Reader.

Method Summary

Modifier and Type	Method and Description
void	close()
boolean	getBufferingMode() Gets the buffering mode indicating whether the reader is currently in buffering mode or non-buffering mode.
int	read() Reads the next character of data from this reader.
int	read(char[] ch) Reads up to c.length characters of data from this reader into the array of characters.
int	read(char[] ch, int offset, int len) Reads up to len characters of data from this reader into an array of characters at the position specified by offset.
void	resetStream(boolean bufferingMode) Resets the reader such that it can be re-read.
void	setBufferingMode(boolean mode) Set the reader into the desired mode.

Methods inherited from class java.io.Reader

mark, markSupported, read, ready, reset, skip

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ParserReader

public ParserReader(Reader reader)

Constructs a ParserReader from a Reader.

Parameters:

reader - the Reader

(Unpublished)

Method Detail

read

public int read()
         throws IOException

Reads the next character of data from this reader.

The character is returned as an int in the range 0 to 16383. If no character is available because the end of the stream has been reached, the value -1 is returned.

Overrides:

read in class Reader

Returns:

the charcater read, or -1 when the end of the stream has been reached

Throws:

IOException - if an I/O error occurs

(Unpublished)

read

public int read(char[] ch)
         throws IOException

Reads up to c.length characters of data from this reader into the array of characters.

Overrides:

read in class Reader

Parameters:

ch - the buffer into which the data is read

Returns:

the total number of characters read into the buffer, or -1 when the end of the stream has been reached

Throws:

IOException - if an I/O error occurs

(Unpublished)

read

public int read(char[] ch,
                int offset,
                int len)
         throws IOException

Reads up to len characters of data from this reader into an array of characters at the position specified by offset.

Specified by:

read in class Reader

Parameters:

ch - the buffer into which the data is read

offset - the start offset of the data

len - the maximum number of characters read

Returns:

the total number of characters read into the buffer, or -1 when the end of the stream has been reached

Throws:

IOException - if an I/O error occurs

(Unpublished)

setBufferingMode

public void setBufferingMode(boolean mode)

Set the reader into the desired mode.

If true is passed in, the reader is put into buffering mode, so that it can be reset subsequently to re-read the data. If false is passed in, the reader is put into non-buffering mode, and it cannot be subsequently reset.

Parameters:

mode - can be true or false, indicating whether the reader should be put into buffering mode or non-buffering mode mode

(Unpublished)

getBufferingMode

public boolean getBufferingMode()

Gets the buffering mode indicating whether the reader is currently in buffering mode or non-buffering mode.

Returns:

true or false, indicating whether the reader is currently in buffering or non-buffering mode

(Unpublished)

resetStream

public void resetStream(boolean bufferingMode)
                 throws IfsException

Resets the reader such that it can be re-read. The reader can continue to operate in buffering mode after the reset, or it can be set to non buffering mode following reset. The buffering mode should be set according to how many times the stream is going to be re-read.

Parameters:

bufferingMode - determines whether the reader should continue in buffering mode after being reset.

Throws:

IfsException - if attempting to reset a reader that is not in buffering mode

(Unpublished)

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Specified by:

close in class Reader

Throws:

IOException

(Unpublished)