de.schlichtherle.truezip.rof

Interface ReadOnlyFile

All Superinterfaces:

AutoCloseable, Closeable

All Known Implementing Classes:

AbstractReadOnlyFile, BufferedReadOnlyFile, ByteArrayReadOnlyFile, CipherReadOnlyFile, DecoratingReadOnlyFile, DefaultReadOnlyFile, DisconnectingReadOnlyFile, IntervalReadOnlyFile, LockReadOnlyFile, RaesReadOnlyFile

@NotThreadSafe
 @CleanupObligation
public interface ReadOnlyFile
extends Closeable

Provides random read-only access to a file. The methods of this interface form a subset of RandomAccessFile which is required for random read-only access. The default implementation can be found in DefaultReadOnlyFile.

Author:

Christian Schlichtherle

Method Summary

Modifier and Type	Method and Description
void	close() Closes this read-only file and releases any non-heap resources allocated for it.
long	getFilePointer() Returns the current byte position in the file as a zero-based index.
long	length() Returns the length of the file in bytes.
int	read() Reads and returns the next byte or -1 if the end of the file has been reached.
int	read(byte[] b) Equivalent to read(b, 0, b.length).
int	read(byte[] b, int off, int len) Reads up to len bytes of data from this read only file into the given array.
void	readFully(byte[] buf) Equivalent to readFully(b, 0, b.length).
void	readFully(byte[] buf, int off, int len) Reads len bytes into the given buffer at the given position.
void	seek(long pos) Sets the current byte position in the file as a zero-based index at which the next read occurs.

Method Detail

close

@DischargesObligation
void close()
                          throws IOException

Closes this read-only file and releases any non-heap resources allocated for it.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException - On any I/O failure.

getFilePointer

long getFilePointer()
             throws IOException

Returns the current byte position in the file as a zero-based index.

Returns:

The current byte position in the file as a zero-based index.

Throws:

IOException - On any I/O failure.

length

long length()
     throws IOException

Returns the length of the file in bytes.

Returns:

The length of the file in bytes.

Throws:

IOException - On any I/O failure.

read

int read()
  throws IOException

Reads and returns the next byte or -1 if the end of the file has been reached.

Returns:

The next byte or -1 if the end of the file has been reached.

Throws:

IOException - On any I/O failure.

read

int read(byte[] b)
  throws IOException

Equivalent to read(b, 0, b.length).

Parameters:

b - The buffer to fill with data.

Returns:

The total number of bytes read, or -1 if there is no more data because the end of the file has been reached.

Throws:

IOException - On any I/O failure.

read

int read(byte[] b,
         int off,
         int len)
  throws IOException

Reads up to len bytes of data from this read only file into the given array. This method blocks until at least one byte of input is available unless len is zero.

Parameters:

b - The buffer to fill with data.

off - The start offset of the data.

len - The maximum number of bytes to read.

Returns:

The total number of bytes read, or -1 if there is no more data because the end of the file has been reached.

Throws:

IOException - On any I/O failure.

readFully

void readFully(byte[] buf)
        throws IOException

Equivalent to readFully(b, 0, b.length).

Parameters:

buf - the buffer to fill with data.

Throws:

EOFException - If less than len bytes are available before the end of the file is reached.

IOException - On any I/O failure.

readFully

void readFully(byte[] buf,
               int off,
               int len)
        throws IOException

Reads len bytes into the given buffer at the given position.

Parameters:

buf - the buffer to fill with data.

off - the start offset of the data.

len - the number of bytes to read.

Throws:

EOFException - If less than len bytes are available before the end of the file is reached.

IOException - On any I/O failure.

seek

void seek(long pos)
   throws IOException

Sets the current byte position in the file as a zero-based index at which the next read occurs. Whether the offset may be set beyond the end of the file is up to the implementor. For example, the constructor of the class DefaultReadOnlyFile passes "r" as a parameter to the constructor of its super-class RandomAccessFile. With Oracle's JSE implementation, on the Windows platform this implementation allows to seek past the end of file, but on the Linux platform it doesn't.

Parameters:

pos - The current byte position as a zero-based index.

Throws:

IOException - If pos is less than 0 or on any I/O failure.