com.amazonaws.services.s3.internal

Class AbstractRepeatableCipherInputStream<T>

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

com.amazonaws.internal.SdkFilterInputStream

com.amazonaws.services.s3.internal.AbstractRepeatableCipherInputStream<T>

Type Parameters:

T - The input stream.

All Implemented Interfaces:

com.amazonaws.internal.MetricAware, java.io.Closeable, java.lang.AutoCloseable

Direct Known Subclasses:

RepeatableCipherInputStream

public abstract class AbstractRepeatableCipherInputStream<T>
extends com.amazonaws.internal.SdkFilterInputStream

Common base class used to wrap an InputStream with a cipher input stream to encrypt it, and handles resets by attempting to reset on the original, unencrypted data InputStream, and recreate an identical Cipher and identical CipherInputStream on the original data.

It's repeatable if and only if the underlying unencryptedDataStream is repeatable - if the underlying input stream is not repeatable and you're going to buffer to make it repeatable anyways, it makes more sense to do so after wrapping in this object, so we buffer the encrypted data and don't have to bother re-encrypting on retry.

This stream only supports being marked before the first call to read or skip, since it's not possible to rewind the encryption state of a CipherInputStream to an arbitrary point. If you call mark after calling read or skip, it will throw an UnsupportedOperationException.

Field Summary

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractRepeatableCipherInputStream(java.io.InputStream input, java.io.FilterInputStream cipherInputStream, T cipherFactory) Constructs a new repeatable cipher input stream using the specified InputStream as the source data, and the CipherFactory for building Cipher objects.

Method Summary

Modifier and Type	Method and Description
protected abstract java.io.FilterInputStream	createCipherInputStream(java.io.InputStream unencryptedDataStream, T cipherFactory)
void	mark(int readlimit)
boolean	markSupported()
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)
void	reset()
long	skip(long n)

Methods inherited from class com.amazonaws.internal.SdkFilterInputStream

abort, abortIfNeeded, available, close, isMetricActivated

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractRepeatableCipherInputStream

protected AbstractRepeatableCipherInputStream(java.io.InputStream input,
                                              java.io.FilterInputStream cipherInputStream,
                                              T cipherFactory)

Constructs a new repeatable cipher input stream using the specified InputStream as the source data, and the CipherFactory for building Cipher objects.

Parameters:

input - The original, unencrypted data stream. This stream should be markable/resetable in order for this class to work correctly.

cipherInputStream - The cipher input stream wrapping the original input stream

cipherFactory - The factory used for creating identical cipher objects when this stream is reset and a new CipherInputStream is needed.

Method Detail

markSupported

public boolean markSupported()

Overrides:

markSupported in class com.amazonaws.internal.SdkFilterInputStream

mark

public void mark(int readlimit)

Overrides:

mark in class com.amazonaws.internal.SdkFilterInputStream

reset

public void reset()
           throws java.io.IOException

Overrides:

reset in class com.amazonaws.internal.SdkFilterInputStream

Throws:

java.io.IOException

read

public int read()
         throws java.io.IOException

Overrides:

read in class com.amazonaws.internal.SdkFilterInputStream

Throws:

java.io.IOException

read

public int read(byte[] b)
         throws java.io.IOException

Overrides:

read in class java.io.FilterInputStream

Throws:

java.io.IOException

read

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

Overrides:

read in class com.amazonaws.internal.SdkFilterInputStream

Throws:

java.io.IOException

skip

public long skip(long n)
          throws java.io.IOException

Overrides:

skip in class com.amazonaws.internal.SdkFilterInputStream

Throws:

java.io.IOException

createCipherInputStream

protected abstract java.io.FilterInputStream createCipherInputStream(java.io.InputStream unencryptedDataStream,
                                                                     T cipherFactory)