Package org.apache.druid.java.util.common

Class StreamUtils

java.lang.Object

org.apache.druid.java.util.common.StreamUtils

public class StreamUtils
extends Object

Constructor Summary

Constructors

Constructor	Description
StreamUtils()

Method Summary

Modifier and Type	Method	Description
static long	copyAndClose(InputStream is, OutputStream os)	Copy from `is` to `os` and close the streams regardless of the result.
static long	copyToFileAndClose(InputStream is, File file)	Copy from an input stream to a file (and buffer it) and close the input stream.
static long	retryCopy(com.google.common.io.ByteSource byteSource, com.google.common.io.ByteSink byteSink, com.google.common.base.Predicate<Throwable> shouldRetry, int maxAttempts)	Retry copy attempts from input stream to output stream.

Methods inherited from class java.lang.Object

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

Constructor Detail

StreamUtils

public StreamUtils()

Method Detail

copyToFileAndClose

public static long copyToFileAndClose(InputStream is,
                                      File file)
                               throws IOException

Copy from an input stream to a file (and buffer it) and close the input stream.

It is highly recommended to use FileUtils.retryCopy whenever possible, and not use a raw `InputStream`

Parameters:

is - The input stream to copy bytes from. `is` is closed regardless of the copy result.

file - The file to copy bytes to. Any parent directories are automatically created.

Returns:

The count of bytes written to the file

Throws:

IOException

copyAndClose

public static long copyAndClose(InputStream is,
                                OutputStream os)
                         throws IOException

Copy from `is` to `os` and close the streams regardless of the result.

Parameters:

is - The `InputStream` to copy results from. It is closed

os - The `OutputStream` to copy results to. It is closed

Returns:

The count of bytes written to `os`

Throws:

IOException

retryCopy

public static long retryCopy(com.google.common.io.ByteSource byteSource,
                             com.google.common.io.ByteSink byteSink,
                             com.google.common.base.Predicate<Throwable> shouldRetry,
                             int maxAttempts)

Retry copy attempts from input stream to output stream. Does *not* check to make sure data was intact during the transfer

Parameters:

byteSource - Supplier for input streams to copy from. The stream is closed on every retry.

byteSink - Supplier for output streams. The stream is closed on every retry.

shouldRetry - Predicate to determine if the throwable is recoverable for a retry

maxAttempts - Maximum number of retries before failing