Package org.apache.commons.compress.utils

Class IOUtils

java.lang.Object

org.apache.commons.compress.utils.IOUtils

public final class IOUtils
extends Object

Utility functions

This class is immutable

(has mutable data but it is write-only)

Field Summary

Fields

Modifier and Type	Field	Description
static final LinkOption[]	EMPTY_LINK_OPTIONS	Empty array of type LinkOption.

Method Summary

Modifier and Type	Method	Description
static void	closeQuietly(Closeable c)	Closes the given Closeable and swallows any IOException that may occur.
static void	copy(File sourceFile, OutputStream outputStream)	Copies the source file to the given output stream.
static long	copy(InputStream input, OutputStream output)	Copies the content of a InputStream into an OutputStream.
static long	copy(InputStream input, OutputStream output, int buffersize)	Copies the content of a InputStream into an OutputStream
static long	copyRange(InputStream input, long len, OutputStream output)	Copies part of the content of a InputStream into an OutputStream.
static long	copyRange(InputStream input, long len, OutputStream output, int buffersize)	Copies part of the content of a InputStream into an OutputStream
static int	read(File file, byte[] array)	Reads as much from the file as possible to fill the given array.
static int	readFully(InputStream input, byte[] array)	Reads as much from input as possible to fill the given array.
static int	readFully(InputStream input, byte[] array, int offset, int len)	Reads as much from input as possible to fill the given array with the given amount of bytes.
static void	readFully(ReadableByteChannel channel, ByteBuffer byteBuffer)	Reads b.remaining() bytes from the given channel starting at the current channel's position.
static byte[]	readRange(InputStream input, int len)	Gets part of the contents of an InputStream as a byte[].
static byte[]	readRange(ReadableByteChannel input, int len)	Gets part of the contents of an ReadableByteChannel as a byte[].
static long	skip(InputStream input, long numToSkip)	Skips the given number of bytes by repeatedly invoking skip on the given input stream if necessary.
static byte[]	toByteArray(InputStream input)	Gets the contents of an InputStream as a byte[].

Methods inherited from class java.lang.Object

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

Field Details

EMPTY_LINK_OPTIONS

public static final LinkOption[] EMPTY_LINK_OPTIONS

Empty array of type LinkOption.

Since:

1.21

Method Details

closeQuietly

public static void closeQuietly(Closeable c)

Closes the given Closeable and swallows any IOException that may occur.

Parameters:

c - Closeable to close, can be null

Since:

1.7

copy

public static void copy(File sourceFile,
 OutputStream outputStream)
                 throws IOException

Copies the source file to the given output stream.

Parameters:

sourceFile - The file to read.

outputStream - The output stream to write.

Throws:

IOException - if an I/O error occurs when reading or writing.

Since:

1.21

copy

public static long copy(InputStream input,
 OutputStream output)
                 throws IOException

Copies the content of a InputStream into an OutputStream. Uses a default buffer size of 8024 bytes.

Parameters:

input - the InputStream to copy

output - the target, may be null to simulate output to dev/null on Linux and NUL on Windows

Returns:

the number of bytes copied

Throws:

IOException - if an error occurs

copy

public static long copy(InputStream input,
 OutputStream output,
 int buffersize)
                 throws IOException

Copies the content of a InputStream into an OutputStream

Parameters:

input - the InputStream to copy

output - the target, may be null to simulate output to dev/null on Linux and NUL on Windows

buffersize - the buffer size to use, must be bigger than 0

Returns:

the number of bytes copied

Throws:

IOException - if an error occurs

IllegalArgumentException - if buffersize is smaller than or equal to 0

copyRange

public static long copyRange(InputStream input,
 long len,
 OutputStream output)
                      throws IOException

Copies part of the content of a InputStream into an OutputStream. Uses a default buffer size of 8024 bytes.

Parameters:

input - the InputStream to copy

output - the target Stream

len - maximum amount of bytes to copy

Returns:

the number of bytes copied

Throws:

IOException - if an error occurs

Since:

1.21

copyRange

public static long copyRange(InputStream input,
 long len,
 OutputStream output,
 int buffersize)
                      throws IOException

Copies part of the content of a InputStream into an OutputStream

Parameters:

input - the InputStream to copy

len - maximum amount of bytes to copy

output - the target, may be null to simulate output to dev/null on Linux and NUL on Windows

buffersize - the buffer size to use, must be bigger than 0

Returns:

the number of bytes copied

Throws:

IOException - if an error occurs

IllegalArgumentException - if buffersize is smaller than or equal to 0

Since:

1.21

read

public static int read(File file,
 byte[] array)
                throws IOException

Reads as much from the file as possible to fill the given array.

This method may invoke read repeatedly to fill the array and only read less bytes than the length of the array if the end of the stream has been reached.

Parameters:

file - file to read

array - buffer to fill

Returns:

the number of bytes actually read

Throws:

IOException - on error

Since:

1.20

readFully

public static int readFully(InputStream input,
 byte[] array)
                     throws IOException

Reads as much from input as possible to fill the given array.

This method may invoke read repeatedly to fill the array and only read less bytes than the length of the array if the end of the stream has been reached.

Parameters:

input - stream to read from

array - buffer to fill

Returns:

the number of bytes actually read

Throws:

IOException - on error

readFully

public static int readFully(InputStream input,
 byte[] array,
 int offset,
 int len)
                     throws IOException

Reads as much from input as possible to fill the given array with the given amount of bytes.

This method may invoke read repeatedly to read the bytes and only read less bytes than the requested length if the end of the stream has been reached.

Parameters:

input - stream to read from

array - buffer to fill

offset - offset into the buffer to start filling at

len - of bytes to read

Returns:

the number of bytes actually read

Throws:

IOException - if an I/O error has occurred

readFully

public static void readFully(ReadableByteChannel channel,
 ByteBuffer byteBuffer)
                      throws IOException

Reads b.remaining() bytes from the given channel starting at the current channel's position.

This method reads repeatedly from the channel until the requested number of bytes are read. This method blocks until the requested number of bytes are read, the end of the channel is detected, or an exception is thrown.

Parameters:

channel - the channel to read from

byteBuffer - the buffer into which the data is read.

Throws:

IOException - - if an I/O error occurs.

EOFException - - if the channel reaches the end before reading all the bytes.

readRange

public static byte[] readRange(InputStream input,
 int len)
                        throws IOException

Gets part of the contents of an InputStream as a byte[].

Parameters:

input - the InputStream to read from

len - maximum amount of bytes to copy

Returns:

the requested byte array

Throws:

NullPointerException - if the input is null

IOException - if an I/O error occurs

Since:

1.21

readRange

public static byte[] readRange(ReadableByteChannel input,
 int len)
                        throws IOException

Gets part of the contents of an ReadableByteChannel as a byte[].

Parameters:

input - the ReadableByteChannel to read from

len - maximum amount of bytes to copy

Returns:

the requested byte array

Throws:

NullPointerException - if the input is null

IOException - if an I/O error occurs

Since:

1.21

skip

public static long skip(InputStream input,
 long numToSkip)
                 throws IOException

Skips the given number of bytes by repeatedly invoking skip on the given input stream if necessary.

In a case where the stream's skip() method returns 0 before the requested number of bytes has been skip this implementation will fall back to using the read() method.

This method will only skip less than the requested number of bytes if the end of the input stream has been reached.

Parameters:

input - stream to skip bytes in

numToSkip - the number of bytes to skip

Returns:

the number of bytes actually skipped

Throws:

IOException - on error

toByteArray

public static byte[] toByteArray(InputStream input)
                          throws IOException

Gets the contents of an InputStream as a byte[].

This method buffers the input internally, so there is no need to use a BufferedInputStream.

Parameters:

input - the InputStream to read from

Returns:

the requested byte array

Throws:

NullPointerException - if the input is null

IOException - if an I/O error occurs

Since:

1.5