Android APIs
public class

BackupDataInputStream

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

Class Overview

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(byte[] b)
Read enough entity data into a byte array to fill the array.
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 size()
Report the total number of bytes of data available for the current entity.
[Expand]
Inherited Methods
From class java.io.InputStream
From class java.lang.Object
From interface java.io.Closeable
From interface java.lang.AutoCloseable

Public Methods

public String getKey ()

Added in API level 8

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

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

public int read (byte[] b)

Added in API level 8

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

public int read ()

Added in API level 8

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

public int read (byte[] b, int offset, int size)

Added in API level 8

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

public int size ()

Added in API level 8

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

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