com.android.tools.build.apkzlib.bytestorage

Class OverflowToDiskByteStorage

java.lang.Object

com.android.tools.build.apkzlib.bytestorage.OverflowToDiskByteStorage

All Implemented Interfaces:

ByteStorage, java.io.Closeable, java.lang.AutoCloseable

public class OverflowToDiskByteStorage
extends java.lang.Object
implements ByteStorage

Byte storage that keeps data in memory up to a certain size. After that, older sources are moved to disk and the newer ones served from memory.

Once unloaded to disk, sources are not reloaded into memory as that would be in direct conflict with the filesystem's caching and the costs would probably outweight the benefits.

The maximum memory used by storage is actually larger than the maximum provided. It may exceed the limit by the size of one source. That is because sources are always loaded into memory before the storage decides to flush them to disk.

Constructor Summary

Constructors

Constructor and Description
OverflowToDiskByteStorage(long memoryCacheSize, TemporaryDirectoryFactory temporaryDirectoryFactory) Creates a new byte storage with the given memory cache size using the provided temporary directory to write data that overflows the memory size.
OverflowToDiskByteStorage(TemporaryDirectoryFactory temporaryDirectoryFactory) Creates a new byte storage with the default memory cache using the provided temporary directory to write data that overflows the memory size.

Method Summary

Modifier and Type	Method and Description
void	close()
CloseableByteSource	fromSource(com.google.common.io.ByteSource source) Creates a new byte source from another byte source.
CloseableByteSource	fromStream(java.io.InputStream stream) Creates a new byte source by fully reading an input stream.
long	getBytesUsed() Obtains the number of bytes currently used.
long	getDiskBytesUsed() Obtains the number of bytes stored in disk.
long	getMaxBytesUsed() Obtains the maximum number of bytes ever used by this tracker.
long	getMaxDiskBytesUsed() Obtains the maximum number of bytes ever stored in disk.
long	getMaxMemoryBytesUsed() Obtains the maximum number of bytes ever stored in memory.
long	getMemoryBytesUsed() Obtains the number of bytes stored in memory.
CloseableByteSourceFromOutputStreamBuilder	makeBuilder() Creates a builder that is an output stream and can create a byte source.

Methods inherited from class java.lang.Object

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

Constructor Detail

OverflowToDiskByteStorage

public OverflowToDiskByteStorage(TemporaryDirectoryFactory temporaryDirectoryFactory)
                          throws java.io.IOException

Creates a new byte storage with the default memory cache using the provided temporary directory to write data that overflows the memory size.

Parameters:

temporaryDirectoryFactory - the factory used to create a temporary directory where to overflow to; the created directory will be closed when the OverflowToDiskByteStorage object is closed

Throws:

java.io.IOException - failed to create the temporary directory

OverflowToDiskByteStorage

public OverflowToDiskByteStorage(long memoryCacheSize,
                                 TemporaryDirectoryFactory temporaryDirectoryFactory)
                          throws java.io.IOException

Creates a new byte storage with the given memory cache size using the provided temporary directory to write data that overflows the memory size.

Parameters:

memoryCacheSize - the in-memory cache; a value of 0 will effectively disable in-memory caching

temporaryDirectoryFactory - the factory used to create a temporary directory where to overflow to; the created directory will be closed when the OverflowToDiskByteStorage object is closed

Throws:

java.io.IOException - failed to create the temporary directory

Method Detail

fromStream

public CloseableByteSource fromStream(java.io.InputStream stream)
                               throws java.io.IOException

Description copied from interface: ByteStorage

Creates a new byte source by fully reading an input stream.

Specified by:

fromStream in interface ByteStorage

Parameters:

stream - the input stream

Returns:

a byte source containing the cached data from the given stream

Throws:

java.io.IOException - failed to read the stream

makeBuilder

public CloseableByteSourceFromOutputStreamBuilder makeBuilder()
                                                       throws java.io.IOException

Description copied from interface: ByteStorage

Creates a builder that is an output stream and can create a byte source.

Specified by:

makeBuilder in interface ByteStorage

Returns:

a builder where data can be written to and a CloseableByteSource can eventually be obtained from

Throws:

java.io.IOException - failed to create the builder; this may happen if the builder require some preparation such as temporary storage allocation that may fail

fromSource

public CloseableByteSource fromSource(com.google.common.io.ByteSource source)
                               throws java.io.IOException

Description copied from interface: ByteStorage

Creates a new byte source from another byte source.

Specified by:

fromSource in interface ByteStorage

Parameters:

source - the byte source to copy data from

Returns:

the tracked byte source

Throws:

java.io.IOException - failed to read data from the byte source

getBytesUsed

public long getBytesUsed()

Description copied from interface: ByteStorage

Obtains the number of bytes currently used.

Specified by:

getBytesUsed in interface ByteStorage

Returns:

the number of bytes

getMaxBytesUsed

public long getMaxBytesUsed()

Description copied from interface: ByteStorage

Obtains the maximum number of bytes ever used by this tracker.

Specified by:

getMaxBytesUsed in interface ByteStorage

Returns:

the number of bytes

getMemoryBytesUsed

public long getMemoryBytesUsed()

Obtains the number of bytes stored in memory.

getMaxMemoryBytesUsed

public long getMaxMemoryBytesUsed()

Obtains the maximum number of bytes ever stored in memory.

getDiskBytesUsed

public long getDiskBytesUsed()

Obtains the number of bytes stored in disk.

getMaxDiskBytesUsed

public long getMaxDiskBytesUsed()

Obtains the maximum number of bytes ever stored in disk.

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Throws:

java.io.IOException