net.sourceforge.javadpkg.io.impl

Class DataFileSource

java.lang.Object

net.sourceforge.javadpkg.io.impl.DataFileSource

All Implemented Interfaces:

Closeable, AutoCloseable, DataSource

public class DataFileSource
extends Object
implements DataSource

A DataSource implementation based on a file.

Version:

1.0, 26.04.2016 by Gerrit Hohl

Author:

Gerrit Hohl (gerrit-hohl@users.sourceforge.net)

Constructor Summary

Constructors

Constructor and Description
DataFileSource(File file) Creates a source.
DataFileSource(File file, boolean resettable) Creates a source.

Method Summary

Modifier and Type	Method and Description
void	close()
InputStream	getInputStream() Returns a stream for reading the data.
long	getLength() Returns the length of the data which can be read from the source in bytes.
String	getName() Returns the name of the source.
boolean	isResettable() Returns the flag if the source can be reseted.
void	reset() Resets the source.

Methods inherited from class java.lang.Object

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

Constructor Detail

DataFileSource

public DataFileSource(File file,
                      boolean resettable)

Creates a source.

The stream on the file will be opened the first time the getInputStream() method is called.

Parameters:

file - The file.

resettable - The flag if the reset() method will be supported.

Throws:

IllegalArgumentException - If the file is null.

DataFileSource

public DataFileSource(File file)

Creates a source.

The stream on the file will be opened the first time the getInputStream() method is called.

The reset() method will be supported.

Parameters:

file - The file.

Throws:

IllegalArgumentException - If the file is null.

Method Detail

getName

public String getName()

Description copied from interface: DataSource

Returns the name of the source.

This name is used e.g. for detail messages of exceptions.

Specified by:

getName in interface DataSource

Returns:

The name.

getLength

public long getLength()

Description copied from interface: DataSource

Returns the length of the data which can be read from the source in bytes.

Specified by:

getLength in interface DataSource

Returns:

The length or -1, if the length is unknown.

isResettable

public boolean isResettable()

Description copied from interface: DataSource

Returns the flag if the source can be reseted.

Specified by:

isResettable in interface DataSource

Returns:

The flag: true, if the source can be reseted, false otherwise.

See Also:

DataSource.reset()

reset

public void reset()
           throws IOException

Description copied from interface: DataSource

Resets the source.

If the source can't be reseted an IOException will be thrown.

If the source can be reseted the next call of the DataSource.getInputStream() method will return a new InputStream which reads the source from the beginning again.

Specified by:

reset in interface DataSource

Throws:

IOException - If an I/O error occurs or if the source doesn't support a reset.

See Also:

DataSource.isResettable()

getInputStream

public InputStream getInputStream()
                           throws IOException

Description copied from interface: DataSource

Returns a stream for reading the data.

The method will always return the same InputStream if the source is still open. If the InputStream.close() method is called the source will behave the same as the Closeable.close() method was called.

If the DataSource.reset() method was successfully called the method will return a different InputStream.

Specified by:

getInputStream in interface DataSource

Returns:

The stream.

Throws:

IOException - If an I/O error occurs.

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException