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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

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.