FileTypeDetector

public abstract class FileTypeDetector
extends Object

java.lang.Object
   ↳ java.nio.file.spi.FileTypeDetector


A file type detector for probing a file to guess its file type.

A file type detector is a concrete implementation of this class, has a zero-argument constructor, and implements the abstract methods specified below.

The means by which a file type detector determines the file type is highly implementation specific. A simple implementation might examine the file extension (a convention used in some platforms) and map it to a file type. In other cases, the file type may be stored as a file attribute or the bytes in a file may be examined to guess its file type.

Summary

Protected constructors

FileTypeDetector()

Initializes a new instance of this class.

Public methods

abstract String probeContentType(Path path)

Probes the given file to guess its content type.

Inherited methods

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.

Protected constructors

FileTypeDetector

Added in API level 26
protected FileTypeDetector ()

Initializes a new instance of this class.

Throws
SecurityException If a security manager has been installed and it denies RuntimePermission("fileTypeDetector")

Public methods

probeContentType

Added in API level 26
public abstract String probeContentType (Path path)

Probes the given file to guess its content type.

The means by which this method determines the file type is highly implementation specific. It may simply examine the file name, it may use a file attribute, or it may examines bytes in the file.

The probe result is the string form of the value of a Multipurpose Internet Mail Extension (MIME) content type as defined by RFC 2045: Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies. The string must be parsable according to the grammar in the RFC 2045.

Parameters
path Path: the path to the file to probe

Returns
String The content type or null if the file type is not recognized

Throws
IOException An I/O error occurs
SecurityException If the implementation requires to access the file, and a security manager is installed, and it denies an unspecified permission required by a file system provider implementation. If the file reference is associated with the default file system provider then the SecurityManager.checkRead(String) method is invoked to check read access to the file.