de.schlichtherle.truezip.rof

Class LockReadOnlyFile

java.lang.Object

de.schlichtherle.truezip.rof.AbstractReadOnlyFile

de.schlichtherle.truezip.rof.DecoratingReadOnlyFile

de.schlichtherle.truezip.rof.LockReadOnlyFile

All Implemented Interfaces:

ReadOnlyFile, Closeable, AutoCloseable

@ThreadSafe
public class LockReadOnlyFile
extends DecoratingReadOnlyFile

A decorator which protects all access to a shared resource, e.g. an InputShop, via a Lock object.

Since:

TrueZIP 7.5

Author:

Christian Schlichtherle

Field Summary

Fields

Modifier and Type	Field and Description
protected Lock	lock The object to synchronize on.

Fields inherited from class de.schlichtherle.truezip.rof.DecoratingReadOnlyFile

delegate

Constructor Summary

Constructors

Constructor and Description
LockReadOnlyFile(ReadOnlyFile rof, Lock lock) Constructs a new synchronized read only file.

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, int off, int len) Reads up to len bytes of data from this read only file into the given array.
void	readFully(byte[] b, 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.

Methods inherited from class de.schlichtherle.truezip.rof.DecoratingReadOnlyFile

toString

Methods inherited from class de.schlichtherle.truezip.rof.AbstractReadOnlyFile

read, readFully

Methods inherited from class java.lang.Object

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

Field Detail

lock

protected final Lock lock

The object to synchronize on.

Constructor Detail

LockReadOnlyFile

@CreatesObligation
public LockReadOnlyFile(@Nullable @WillCloseWhenClosed
                                           ReadOnlyFile rof,
                                           Lock lock)

Constructs a new synchronized read only file.

Parameters:

rof - the input stream to wrap in this decorator.

lock - the object to synchronize on.

Method Detail

close

public void close()
           throws IOException

Description copied from interface: ReadOnlyFile

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

Specified by:

close in interface ReadOnlyFile

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class DecoratingReadOnlyFile

Throws:

IOException - On any I/O failure.

getFilePointer

public long getFilePointer()
                    throws IOException

Description copied from interface: ReadOnlyFile

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

Specified by:

getFilePointer in interface ReadOnlyFile

Overrides:

getFilePointer in class DecoratingReadOnlyFile

Returns:

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

Throws:

IOException - On any I/O failure.

length

public long length()
            throws IOException

Description copied from interface: ReadOnlyFile

Returns the length of the file in bytes.

Specified by:

length in interface ReadOnlyFile

Overrides:

length in class DecoratingReadOnlyFile

Returns:

The length of the file in bytes.

Throws:

IOException - On any I/O failure.

read

public int read()
         throws IOException

Description copied from interface: ReadOnlyFile

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

Specified by:

read in interface ReadOnlyFile

Overrides:

read in class DecoratingReadOnlyFile

Returns:

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

Throws:

IOException - On any I/O failure.

read

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

Description copied from interface: ReadOnlyFile

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.

Specified by:

read in interface ReadOnlyFile

Overrides:

read in class DecoratingReadOnlyFile

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

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

Description copied from interface: ReadOnlyFile

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

Specified by:

readFully in interface ReadOnlyFile

Overrides:

readFully in class AbstractReadOnlyFile

Parameters:

b - 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

public void seek(long pos)
          throws IOException

Description copied from interface: ReadOnlyFile

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.

Specified by:

seek in interface ReadOnlyFile

Overrides:

seek in class DecoratingReadOnlyFile

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.