Added in API level 8

BackupDataInputStream


public class BackupDataInputStream
extends InputStream

java.lang.Object
   ↳ java.io.InputStream
     ↳ android.app.backup.BackupDataInputStream


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

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.

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.

abstract void close()

Closes this stream and releases any system resources associated with it.

abstract void close()

Closes this resource, relinquishing any underlying resources.

Public methods

getKey

Added in API level 8
public String getKey ()

Report the key string associated with this entity within the backup data set.

Returns
String The key string for this entity, equivalent to calling BackupDataInput.getKey() on the underlying BackupDataInput.

read

Added in API level 8
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.

Throws
IOException

read

Added in API level 8
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.

Throws
IOException

read

Added in API level 8
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.

Throws
IOException

size

Added in API level 8
public int size ()

Report the total number of bytes of data available for the current entity.

Returns
int The number of data bytes available, equivalent to calling BackupDataInput.getDataSize() on the underlying BackupDataInput.