de.esprit.common.io

Class NullInputStream

java.lang.Object

java.io.InputStream

de.esprit.common.io.NullInputStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class NullInputStream
extends java.io.InputStream

This is an InputStream that generates dummy data for testing purposes. You may override nextByte() in order to specify what data is produced. By default this stream repeats reading the string '0123456789' until it's size is reached.

Author:

Rainer Buesch

Constructor Summary

Constructors

Constructor and Description
NullInputStream(int numLines) Creates an InputStream with the given number of lines.
NullInputStream(long size) Creates an InputStream with the specified size.
NullInputStream(long size, boolean isMarkSupported, boolean isThrowEOF) Creates an InputStream with the specified size.

Method Summary

Methods

Modifier and Type	Method and Description
int	available() Return the number of bytes that are still available in the stream.
void	close() Closes and resets this stream.
protected int	fetchByte() Return a byte value for the read() method.
long	getPosition() Return the current position in the stream.
long	getSize() Return the size of this InputStream.
void	mark(int readLimit) Marks the current position.
boolean	markSupported() Tells whether mark() is supported.
protected byte	nextByte() Is called whenever a byte is read from the stream.
int	read() Read the next byte from the stream.
int	read(byte[] bytes) Fill bytes into the given array.
int	read(byte[] bytes, int offset, int length) Fills the given array from offset with length bytes.
void	reset() Reset the stream to the last called mark.
long	skip(long bytesToSkip) Skip a specified number of bytes.

Methods inherited from class java.lang.Object

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

Constructor Detail

NullInputStream

public NullInputStream(int numLines)

Creates an InputStream with the given number of lines. The size is calculated by adding a platform specific line separator to each line.

NullInputStream

public NullInputStream(long size)

Creates an InputStream with the specified size. It supports marking and does not throw EOFException.

NullInputStream

public NullInputStream(long size,
               boolean isMarkSupported,
               boolean isThrowEOF)

Creates an InputStream with the specified size.

Parameters:

size - The size of the input stream

isMarkSupported - Tells whether this streams supports mark()

isThrowEOF - throw an EOFException when EOF is reached, otherwise return -1.

Method Detail

getPosition

public long getPosition()

Return the current position in the stream.

getSize

public long getSize()

Return the size of this InputStream.

available

public int available()

Return the number of bytes that are still available in the stream.

Overrides:

available in class java.io.InputStream

close

public void close()
           throws java.io.IOException

Closes and resets this stream.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Overrides:

close in class java.io.InputStream

Throws:

java.io.IOException

mark

public void mark(int readLimit)

Marks the current position.

Overrides:

mark in class java.io.InputStream

Parameters:

readLimit - the maximum limit of bytes that can be read before the mark position becomes invalid.

Throws:

java.lang.UnsupportedOperationException - if mark is not supported.

markSupported

public boolean markSupported()

Tells whether mark() is supported.

Overrides:

markSupported in class java.io.InputStream

read

public int read()
         throws java.io.IOException

Read the next byte from the stream.

Specified by:

read in class java.io.InputStream

Throws:

java.io.IOException

read

public int read(byte[] bytes)
         throws java.io.IOException

Fill bytes into the given array.

Overrides:

read in class java.io.InputStream

Parameters:

bytes - The byte array to be filled

Returns:

The number of bytes or -1 on EOF

Throws:

java.io.IOException

read

public int read(byte[] bytes,
       int offset,
       int length)
         throws java.io.IOException

Fills the given array from offset with length bytes.

Overrides:

read in class java.io.InputStream

Parameters:

bytes - The byte array to be filled

Returns:

The number of bytes or -1 on EOF

Throws:

java.io.IOException

reset

public void reset()
           throws java.io.IOException

Reset the stream to the last called mark.

Overrides:

reset in class java.io.InputStream

Throws:

java.lang.UnsupportedOperationException - if mark is not supported.

java.io.IOException - If no position has been marked or the read limit has been exceeded since the last position was marked.

skip

public long skip(long bytesToSkip)
          throws java.io.IOException

Skip a specified number of bytes.

Overrides:

skip in class java.io.InputStream

Parameters:

bytesToSkip - The number of bytes skipped.

Returns:

The number of bytes skipped or -1 when EOF was reached

Throws:

java.io.IOException

fetchByte

protected int fetchByte()

Return a byte value for the read() method.

This implementation returns zero.

Returns:

This implementation always returns zero.

nextByte

protected byte nextByte()

Is called whenever a byte is read from the stream. May be overridden to return test-data other than the default.