public
class
BackupDataInputStream
extends InputStream
Provides an InputStream
-like interface for accessing an
entity's data during a restore operation. Used by BackupHelper
classes within the BackupAgentHelper
mechanism.
When BackupHelper.restoreEntity()
is called, the current entity's header has already been read from the underlying
BackupDataInput
. The entity's key string and total data size are available
through this class's getKey()
and size()
methods, respectively.
Note: The caller should take care not to seek or close the underlying data
source, nor read more than size()
bytes from the stream.
Summary
Public methods |
String
|
getKey()
Report the key string associated with this entity within the backup data set.
|
int
|
read()
Read one byte of entity data from the stream, returning it as
an integer value.
|
int
|
read(byte[] b, int offset, int size)
Read up to size bytes of data into a byte array, beginning at position
offset within the array.
|
int
|
read(byte[] b)
Read enough entity data into a byte array to fill the array.
|
int
|
size()
Report the total number of bytes of data available for the current entity.
|
Inherited methods |
From class
java.io.InputStream
int
|
available()
Returns an estimate of the number of bytes that can be read (or skipped
over) from this input stream without blocking, which may be 0, or 0 when
end of stream is detected.
|
void
|
close()
Closes this input stream and releases any system resources associated
with the stream.
|
void
|
mark(int readlimit)
Marks the current position in this input stream.
|
boolean
|
markSupported()
Tests if this input stream supports the mark and
reset methods.
|
static
InputStream
|
nullInputStream()
Returns a new InputStream that reads no bytes.
|
int
|
read(byte[] b)
Reads some number of bytes from the input stream and stores them into
the buffer array b .
|
abstract
int
|
read()
Reads the next byte of data from the input stream.
|
int
|
read(byte[] b, int off, int len)
Reads up to len bytes of data from the input stream into
an array of bytes.
|
byte[]
|
readAllBytes()
Reads all remaining bytes from the input stream.
|
int
|
readNBytes(byte[] b, int off, int len)
Reads the requested number of bytes from the input stream into the given
byte array.
|
byte[]
|
readNBytes(int len)
Reads up to a specified number of bytes from the input stream.
|
void
|
reset()
Repositions this stream to the position at the time the
mark method was last called on this input stream.
|
long
|
skip(long n)
Skips over and discards n bytes of data from this input
stream.
|
void
|
skipNBytes(long n)
Skips over and discards exactly n bytes of data from this input
stream.
|
long
|
transferTo(OutputStream out)
Reads all bytes from this input stream and writes the bytes to the
given output stream in the order that they are read.
|
|
From class
java.lang.Object
Object
|
clone()
Creates and returns a copy of this object.
|
boolean
|
equals(Object obj)
Indicates whether some other object is "equal to" this one.
|
void
|
finalize()
Called by the garbage collector on an object when garbage collection
determines that there are no more references to the object.
|
final
Class<?>
|
getClass()
Returns the runtime class of this Object .
|
int
|
hashCode()
Returns a hash code value for the object.
|
final
void
|
notify()
Wakes up a single thread that is waiting on this object's
monitor.
|
final
void
|
notifyAll()
Wakes up all threads that are waiting on this object's monitor.
|
String
|
toString()
Returns a string representation of the object.
|
final
void
|
wait(long timeoutMillis, int nanos)
Causes the current thread to wait until it is awakened, typically
by being notified or interrupted, or until a
certain amount of real time has elapsed.
|
final
void
|
wait(long timeoutMillis)
Causes the current thread to wait until it is awakened, typically
by being notified or interrupted, or until a
certain amount of real time has elapsed.
|
final
void
|
wait()
Causes the current thread to wait until it is awakened, typically
by being notified or interrupted.
|
|
From interface
java.io.Closeable
abstract
void
|
close()
Closes this stream and releases any system resources associated
with it.
|
|
From interface
java.lang.AutoCloseable
abstract
void
|
close()
Closes this resource, relinquishing any underlying resources.
|
|
Public methods
getKey
public String getKey ()
Report the key string associated with this entity within the backup data set.
read
public int read ()
Read one byte of entity data from the stream, returning it as
an integer value. If more than size()
bytes of data
are read from the stream, the output of this method is undefined.
Returns |
int |
The byte read, or undefined if the end of the stream has been reached. |
read
public int read (byte[] b,
int offset,
int size)
Read up to size
bytes of data into a byte array, beginning at position
offset
within the array.
Parameters |
b |
byte : Byte array into which the data will be read |
offset |
int : The data will be stored in b beginning at this index
within the array. |
size |
int : The number of bytes to read in this operation. If insufficient
data exists within the entity to fulfill this request, only as much data
will be read as is available. |
Returns |
int |
The number of bytes of data read, or zero if all of the entity's
data has already been read. |
read
public int read (byte[] b)
Read enough entity data into a byte array to fill the array.
Parameters |
b |
byte : Byte array to fill with data from the stream. If the stream does not
have sufficient data to fill the array, then the contents of the remainder of
the array will be undefined. |
Returns |
int |
The number of bytes of data read, or zero if all of the entity's
data has already been read. |
size
public int size ()
Report the total number of bytes of data available for the current entity.