Package org.apache.tika.parser.html.charsetdetector

Class StandardHtmlEncodingDetector

java.lang.Object

org.apache.tika.parser.html.charsetdetector.StandardHtmlEncodingDetector

All Implemented Interfaces:

Serializable, SelfConfiguring, EncodingDetector

public final class StandardHtmlEncodingDetector
extends Object
implements EncodingDetector

Full WHATWG prescan charset detector for HTML: HTTP Content-Type header → <meta charset> / <meta http-equiv> tag, per https://html.spec.whatwg.org/multipage/parsing.html#the-input-byte-stream.

BOM detection is not performed here; BOMDetector handles that as a separate, earlier step in the detector chain.

Opt-in: register explicitly in a <encodingDetectors> config to use this detector in place of the lenient HtmlEncodingDetector default.

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
StandardHtmlEncodingDetector()

Method Summary

Modifier and Type	Method	Description
List<EncodingResult>	detect(TikaInputStream tis, Metadata metadata, ParseContext context)	Detects the character encoding of the given text document.
int	getMarkLimit()
void	setMarkLimit(int markLimit)	How far into the stream to scan for a <meta charset> declaration.

Methods inherited from class java.lang.Object

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

Constructor Details

StandardHtmlEncodingDetector

public StandardHtmlEncodingDetector()

Method Details

detect

public List<EncodingResult> detect(TikaInputStream tis,
 Metadata metadata,
 ParseContext context)
                            throws IOException

Description copied from interface: EncodingDetector

Detects the character encoding of the given text document.

Returns an empty list if the encoding cannot be determined. Returns a ranked list of candidates in descending confidence order otherwise. The first entry is always the best guess.

If the document input stream is not available, then the first argument may be null. Otherwise the detector may read bytes from the start of the stream to help in encoding detection. The given stream is guaranteed to support the mark feature and the detector is expected to mark the stream before reading any bytes from it, and to reset the stream before returning. The stream must not be closed by the detector.

The given input metadata is only read, not modified, by the detector.

Specified by:

detect in interface EncodingDetector

Parameters:

tis - text document input stream, or null

metadata - input metadata for the document

context - the parse context

Returns:

ranked list of encoding results, empty if unknown; never null

Throws:

IOException - if the document input stream could not be read

getMarkLimit

public int getMarkLimit()

setMarkLimit

public void setMarkLimit(int markLimit)

How far into the stream to scan for a <meta charset> declaration. Default is 65536 bytes.