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Android APIs
public class

StatFs

extends Object
java.lang.Object
   ↳ android.os.StatFs

Class Overview

Retrieve overall information about the space on a filesystem. This is a Wrapper for Unix statfs().

Summary

Public Constructors
StatFs(String path)
Construct a new StatFs for looking at the stats of the filesystem at path.
Public Methods
int getAvailableBlocks()
The number of blocks that are free on the file system and available to applications.
int getBlockCount()
The total number of blocks on the file system.
int getBlockSize()
The size, in bytes, of a block on the file system.
int getFreeBlocks()
The total number of blocks that are free on the file system, including reserved blocks (that are not available to normal applications).
void restat(String path)
Perform a restat of the file system referenced by this object.
Protected Methods
void finalize()
Invoked when the garbage collector has detected that this instance is no longer reachable.
[Expand]
Inherited Methods
From class java.lang.Object

Public Constructors

public StatFs (String path)

Since: API Level 1

Construct a new StatFs for looking at the stats of the filesystem at path. Upon construction, the stat of the file system will be performed, and the values retrieved available from the methods on this class.

Parameters
path A path in the desired file system to state.

Public Methods

public int getAvailableBlocks ()

Since: API Level 1

The number of blocks that are free on the file system and available to applications. This corresponds to the Unix statfs.f_bavail field.

public int getBlockCount ()

Since: API Level 1

The total number of blocks on the file system. This corresponds to the Unix statfs.f_blocks field.

public int getBlockSize ()

Since: API Level 1

The size, in bytes, of a block on the file system. This corresponds to the Unix statfs.f_bsize field.

public int getFreeBlocks ()

Since: API Level 1

The total number of blocks that are free on the file system, including reserved blocks (that are not available to normal applications). This corresponds to the Unix statfs.f_bfree field. Most applications will want to use getAvailableBlocks() instead.

public void restat (String path)

Since: API Level 1

Perform a restat of the file system referenced by this object. This is the same as re-constructing the object with the same file system path, and the new stat values are available upon return.

Protected Methods

protected void finalize ()

Since: API Level 1

Invoked when the garbage collector has detected that this instance is no longer reachable. The default implementation does nothing, but this method can be overridden to free resources.

Note that objects that override finalize are significantly more expensive than objects that don't. Finalizers may be run a long time after the object is no longer reachable, depending on memory pressure, so it's a bad idea to rely on them for cleanup. Note also that finalizers are run on a single VM-wide finalizer thread, so doing blocking work in a finalizer is a bad idea. A finalizer is usually only necessary for a class that has a native peer and needs to call a native method to destroy that peer. Even then, it's better to provide an explicit close method (and implement Closeable), and insist that callers manually dispose of instances. This works well for something like files, but less well for something like a BigInteger where typical calling code would have to deal with lots of temporaries. Unfortunately, code that creates lots of temporaries is the worst kind of code from the point of view of the single finalizer thread.

If you must use finalizers, consider at least providing your own ReferenceQueue and having your own thread process that queue.

Unlike constructors, finalizers are not automatically chained. You are responsible for calling super.finalize() yourself.

Uncaught exceptions thrown by finalizers are ignored and do not terminate the finalizer thread. See Effective Java Item 7, "Avoid finalizers" for more.