Package org.apache.commons.compress.archivers

Class ArchiveInputStream<E extends ArchiveEntry>

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

org.apache.commons.compress.archivers.ArchiveInputStream<E>

Type Parameters:

E - The type of ArchiveEntry produced.

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

Direct Known Subclasses:

ArArchiveInputStream, ArjArchiveInputStream, CpioArchiveInputStream, DumpArchiveInputStream, TarArchiveInputStream, ZipArchiveInputStream

public abstract class ArchiveInputStream<E extends ArchiveEntry>
extends java.io.FilterInputStream

Archive input streams MUST override the FilterInputStream.read(byte[], int, int) - or read() - method so that reading from the stream generates EOF for the end of data in each entry as well as at the end of the file proper.

The getNextEntry() method is used to reset the input stream ready for reading the data from the next entry.

The input stream classes must also implement a method with the signature:

 public static boolean matches(byte[] signature, int length)
 

which is used by the ArchiveStreamFactory to autodetect the archive type from the first few bytes of a stream.

Field Summary

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

Constructors

Modifier	Constructor	Description
	ArchiveInputStream()	Constructs a new instance.
protected	ArchiveInputStream(java.io.InputStream inputStream, java.lang.String charsetName)	Constructs a new instance.

Method Summary

Modifier and Type	Method	Description
boolean	canReadEntryData(ArchiveEntry archiveEntry)	Tests whether this stream is able to read the given entry.
protected void	count(int read)	Increments the counter of already read bytes.
protected void	count(long read)	Increments the counter of already read bytes.
void	forEach(org.apache.commons.io.function.IOConsumer<? super E> action)	Performs the given action for each element of the stream until all elements have been processed or the action throws an exception.
long	getBytesRead()	Gets the current number of bytes read from this stream.
java.nio.charset.Charset	getCharset()	Gets the Charset.
int	getCount()	Deprecated. this method may yield wrong results for large archives, use getBytesRead() instead.
abstract E	getNextEntry()	Gets the next Archive Entry in this Stream.
org.apache.commons.io.function.IOIterator<E>	iterator()	Returns an iterator over the SubField elements in this extra field in proper sequence.
void	mark(int readlimit)	Does nothing.
boolean	markSupported()	Always returns false.
protected void	pushedBackBytes(long pushedBack)	Decrements the counter of already read bytes.
int	read()	Reads a byte of data.
void	reset()	Does nothing.

Methods inherited from class java.io.FilterInputStream

available, close, read, read, skip

Methods inherited from class java.io.InputStream

nullInputStream, readAllBytes, readNBytes, readNBytes, transferTo

Methods inherited from class java.lang.Object

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

Constructor Detail

ArchiveInputStream

public ArchiveInputStream()

Constructs a new instance.

ArchiveInputStream

protected ArchiveInputStream(java.io.InputStream inputStream,
                             java.lang.String charsetName)

Constructs a new instance.

Parameters:

inputStream - the underlying input stream, or null if this instance is to be created without an underlying stream.

charsetName - charset name.

Since:

1.26.0

Method Detail

canReadEntryData

public boolean canReadEntryData(ArchiveEntry archiveEntry)

Tests whether this stream is able to read the given entry.

Some archive formats support variants or details that are not supported (yet).

Parameters:

archiveEntry - the entry to test.

Returns:

This implementation always returns true.

Since:

1.1

count

protected void count(int read)

Increments the counter of already read bytes. Doesn't increment if the EOF has been hit (read == -1).

Parameters:

read - the number of bytes read.

count

protected void count(long read)

Increments the counter of already read bytes. Doesn't increment if the EOF has been hit (read == -1).

Parameters:

read - the number of bytes read.

Since:

1.1

forEach

public void forEach(org.apache.commons.io.function.IOConsumer<? super E> action)
             throws java.io.IOException

Performs the given action for each element of the stream until all elements have been processed or the action throws an exception. Actions are performed in the order of iteration. Exceptions thrown by the action are relayed to the caller.

The behavior of this method is unspecified if the action performs side-effects that modify the underlying source of elements, unless an overriding class has specified a concurrent modification policy.

Parameters:

action - The action to be performed for each element.

Throws:

java.io.IOException - if an I/O error occurs.

java.lang.NullPointerException - if the specified action is null.

Since:

1.27.0

getBytesRead

public long getBytesRead()

Gets the current number of bytes read from this stream.

Returns:

the number of read bytes.

Since:

1.1

getCharset

public java.nio.charset.Charset getCharset()

Gets the Charset.

Returns:

the Charset.

getCount

@Deprecated
public int getCount()

Deprecated.

this method may yield wrong results for large archives, use getBytesRead() instead.

Gets the current number of bytes read from this stream.

Returns:

the number of read.

getNextEntry

public abstract E getNextEntry()
                        throws java.io.IOException

Gets the next Archive Entry in this Stream.

Returns:

the next entry, or null if there are no more entries.

Throws:

java.io.IOException - if the next entry could not be read.

iterator

public org.apache.commons.io.function.IOIterator<E> iterator()

Returns an iterator over the SubField elements in this extra field in proper sequence.

Returns:

an iterator over the SubField elements in this extra field in proper sequence.

Since:

1.27.0

mark

public void mark(int readlimit)

Does nothing.

TODO [COMPRESS-670] Support mark() and reset() in ArchiveInputStream.

Overrides:

mark in class java.io.FilterInputStream

Parameters:

readlimit - ignored.

markSupported

public boolean markSupported()

Always returns false.

TODO [COMPRESS-670] Support mark() and reset() in ArchiveInputStream.

Overrides:

markSupported in class java.io.FilterInputStream

Returns:

Always returns false.

pushedBackBytes

protected void pushedBackBytes(long pushedBack)

Decrements the counter of already read bytes.

Parameters:

pushedBack - the number of bytes pushed back.

Since:

1.1

read

public int read()
         throws java.io.IOException

Reads a byte of data. This method will block until enough input is available.

Simply calls the FilterInputStream.read(byte[], int, int) method.

MUST be overridden if the FilterInputStream.read(byte[], int, int) method is not overridden; may be overridden otherwise.

Overrides:

read in class java.io.FilterInputStream

Returns:

the byte read, or -1 if end of input is reached.

Throws:

java.io.IOException - if an I/O error has occurred.

reset

public void reset()
           throws java.io.IOException

Does nothing.

TODO [COMPRESS-670] Support mark() and reset() in ArchiveInputStream.

Overrides:

reset in class java.io.FilterInputStream

Throws:

java.io.IOException - not thrown here but may be thrown from a subclass.