org.apache.commons.compress.archivers

Class ArchiveInputStream<E extends ArchiveEntry>

java.lang.Object

java.io.InputStream

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

Type Parameters:

E - The type of ArchiveEntry produced.

All Implemented Interfaces:

Closeable, AutoCloseable

Direct Known Subclasses:

ArArchiveInputStream, ArjArchiveInputStream, CpioArchiveInputStream, DumpArchiveInputStream, TarArchiveInputStream, ZipArchiveInputStream

public abstract class ArchiveInputStream<E extends ArchiveEntry>
extends InputStream

Archive input streams MUST override the InputStream.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.

Constructor Summary

Constructors

Constructor and Description
ArchiveInputStream()

Method Summary

Modifier and Type	Method and Description
boolean	canReadEntryData(ArchiveEntry archiveEntry) 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.
long	getBytesRead() Returns the current number of bytes read from this stream.
int	getCount() Deprecated. this method may yield wrong results for large archives, use #getBytesRead instead
abstract E	getNextEntry() Returns the next Archive Entry in this Stream.
protected void	pushedBackBytes(long pushedBack) Decrements the counter of already read bytes.
int	read() Reads a byte of data.

Methods inherited from class java.io.InputStream

available, close, mark, markSupported, read, read, reset, skip

Methods inherited from class java.lang.Object

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

Constructor Detail

ArchiveInputStream

public ArchiveInputStream()

Method Detail

canReadEntryData

public boolean canReadEntryData(ArchiveEntry archiveEntry)

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

getBytesRead

public long getBytesRead()

Returns the current number of bytes read from this stream.

Returns:

the number of read bytes

Since:

1.1

getCount

@Deprecated
public int getCount()

Deprecated. this method may yield wrong results for large archives, use #getBytesRead instead

Returns the current number of bytes read from this stream.

Returns:

the number of read bytes

getNextEntry

public abstract E getNextEntry()
                        throws IOException

Returns the next Archive Entry in this Stream.

Returns:

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

Throws:

IOException - if the next entry could not be read

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 IOException

Reads a byte of data. This method will block until enough input is available. Simply calls the InputStream.read(byte[], int, int) method. MUST be overridden if the InputStream.read(byte[], int, int) method is not overridden; may be overridden otherwise.

Specified by:

read in class InputStream

Returns:

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

Throws:

IOException - if an I/O error has occurred