Package org.elasticsearch.common.io

Class Streams

java.lang.Object

org.elasticsearch.common.io.Streams

public abstract class Streams
extends Object

Simple utility methods for file and stream copying. All copy methods use a block size of 4096 bytes, and close all affected streams when done.

Mainly for use within the framework, but also useful for application code.

Field Summary

Fields

Modifier and Type	Field	Description
static int	BUFFER_SIZE
static OutputStream	NULL_OUTPUT_STREAM	OutputStream that just throws all the bytes away

Constructor Summary

Constructors

Constructor	Description
Streams()

Method Summary

Modifier and Type	Method	Description
static long	consumeFully(InputStream inputStream)	Fully consumes the input stream, throwing the bytes away.
static void	copy(byte[] in, OutputStream out)	Copy the contents of the given byte array to the given OutputStream.
static int	copy(Reader in, Writer out)	Copy the contents of the given Reader to the given Writer.
static void	copy(String in, Writer out)	Copy the contents of the given String to the given output Writer.
static String	copyToString(Reader in)	Copy the contents of the given Reader into a String.
static BytesStream	flushOnCloseStream(BytesStream os)	Wraps the given BytesStream in a StreamOutput that simply flushes when close is called.
static InputStream	limitStream(InputStream in, long limit)	Limits the given input stream to the provided number of bytes
static InputStream	noCloseStream(InputStream stream)	Wraps an InputStream such that it's close method becomes a noop
static OutputStream	noCloseStream(OutputStream stream)	Wraps an OutputStream such that it's close method becomes a noop
static List<String>	readAllLines(InputStream input)
static void	readAllLines(InputStream input, Consumer<String> consumer)
static BytesReference	readFully(InputStream in)	Reads all bytes from the given InputStream and closes it afterwards.
static int	readFully(InputStream reader, byte[] dest)
static int	readFully(InputStream reader, byte[] dest, int offset, int len)
static int	readFully(Reader reader, char[] dest)
static int	readFully(Reader reader, char[] dest, int offset, int len)

Methods inherited from class java.lang.Object

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

Field Details

BUFFER_SIZE

public static final int BUFFER_SIZE

See Also:

Constant Field Values

NULL_OUTPUT_STREAM

public static final OutputStream NULL_OUTPUT_STREAM

OutputStream that just throws all the bytes away

Constructor Details

Streams

public Streams()

Method Details

copy

public static void copy(byte[] in,
 OutputStream out)
                 throws IOException

Copy the contents of the given byte array to the given OutputStream. Closes the stream when done.

Parameters:

in - the byte array to copy from

out - the OutputStream to copy to

Throws:

IOException - in case of I/O errors

copy

public static int copy(Reader in,
 Writer out)
                throws IOException

Copy the contents of the given Reader to the given Writer. Closes both when done.

Parameters:

in - the Reader to copy from

out - the Writer to copy to

Returns:

the number of characters copied

Throws:

IOException - in case of I/O errors

copy

public static void copy(String in,
 Writer out)
                 throws IOException

Copy the contents of the given String to the given output Writer. Closes the write when done.

Parameters:

in - the String to copy from

out - the Writer to copy to

Throws:

IOException - in case of I/O errors

copyToString

public static String copyToString(Reader in)
                           throws IOException

Copy the contents of the given Reader into a String. Closes the reader when done.

Parameters:

in - the reader to copy from

Returns:

the String that has been copied to

Throws:

IOException - in case of I/O errors

readFully

public static int readFully(Reader reader,
 char[] dest)
                     throws IOException

Throws:

IOException

readFully

public static int readFully(Reader reader,
 char[] dest,
 int offset,
 int len)
                     throws IOException

Throws:

IOException

readFully

public static int readFully(InputStream reader,
 byte[] dest)
                     throws IOException

Throws:

IOException

readFully

public static int readFully(InputStream reader,
 byte[] dest,
 int offset,
 int len)
                     throws IOException

Throws:

IOException

consumeFully

public static long consumeFully(InputStream inputStream)
                         throws IOException

Fully consumes the input stream, throwing the bytes away. Returns the number of bytes consumed.

Throws:

IOException

readAllLines

public static List<String> readAllLines(InputStream input)
                                 throws IOException

Throws:

IOException

readAllLines

public static void readAllLines(InputStream input,
 Consumer<String> consumer)
                         throws IOException

Throws:

IOException

noCloseStream

public static InputStream noCloseStream(InputStream stream)

Wraps an InputStream such that it's close method becomes a noop

Parameters:

stream - InputStream to wrap

Returns:

wrapped InputStream

noCloseStream

public static OutputStream noCloseStream(OutputStream stream)

Wraps an OutputStream such that it's close method becomes a noop

Parameters:

stream - OutputStream to wrap

Returns:

wrapped OutputStream

flushOnCloseStream

public static BytesStream flushOnCloseStream(BytesStream os)

Wraps the given BytesStream in a StreamOutput that simply flushes when close is called.

readFully

public static BytesReference readFully(InputStream in)
                                throws IOException

Reads all bytes from the given InputStream and closes it afterwards.

Throws:

IOException

limitStream

public static InputStream limitStream(InputStream in,
 long limit)

Limits the given input stream to the provided number of bytes