Package com.fasterxml.jackson.core.format

Class DataFormatDetector

java.lang.Object

com.fasterxml.jackson.core.format.DataFormatDetector

public class DataFormatDetector
extends Object

Simple helper class that allows data format (content type) auto-detection, given an ordered set of JsonFactory instances to use for actual low-level detection.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_MAX_INPUT_LOOKAHEAD	By default we will look ahead at most 64 bytes; in most cases, much less (4 bytes or so) is needed, but we will allow bit more leniency to support data formats that need more complex heuristics.

Constructor Summary

Constructors

Constructor	Description
DataFormatDetector(JsonFactory... detectors)
DataFormatDetector(Collection<JsonFactory> detectors)

Method Summary

Modifier and Type	Method	Description
DataFormatMatcher	findFormat(byte[] fullInputData)	Method to call to find format that given content (full document) has, as per configuration of this detector instance.
DataFormatMatcher	findFormat(byte[] fullInputData, int offset, int len)	Method to call to find format that given content (full document) has, as per configuration of this detector instance.
DataFormatMatcher	findFormat(InputStream in)	Method to call to find format that content (accessible via given InputStream) given has, as per configuration of this detector instance.
String	toString()
DataFormatDetector	withMaxInputLookahead(int lookaheadBytes)	Method that will return a detector instance that allows detectors to read up to specified number of bytes when determining format match strength.
DataFormatDetector	withMinimalMatch(MatchStrength minMatch)	Method that will return a detector instance that uses given minimal match level; match that may be returned unless a stronger match is found with other format detectors.
DataFormatDetector	withOptimalMatch(MatchStrength optMatch)	Method that will return a detector instance that uses given optimal match level (match that is considered sufficient to return, without trying to find stronger matches with other formats).

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

DEFAULT_MAX_INPUT_LOOKAHEAD

public static final int DEFAULT_MAX_INPUT_LOOKAHEAD

By default we will look ahead at most 64 bytes; in most cases, much less (4 bytes or so) is needed, but we will allow bit more leniency to support data formats that need more complex heuristics.

See Also:

• Constant Field Values

Constructor Details

DataFormatDetector

public DataFormatDetector(JsonFactory... detectors)

DataFormatDetector

public DataFormatDetector(Collection<JsonFactory> detectors)

Method Details

withOptimalMatch

public DataFormatDetector withOptimalMatch(MatchStrength optMatch)

Method that will return a detector instance that uses given optimal match level (match that is considered sufficient to return, without trying to find stronger matches with other formats).

Parameters:

optMatch - Optimal match level to use

Returns:

Format detector instance with specified optimal match level

withMinimalMatch

public DataFormatDetector withMinimalMatch(MatchStrength minMatch)

Method that will return a detector instance that uses given minimal match level; match that may be returned unless a stronger match is found with other format detectors.

Parameters:

minMatch - Minimum match level to use

Returns:

Format detector instance with specified minimum match level

withMaxInputLookahead

public DataFormatDetector withMaxInputLookahead(int lookaheadBytes)

Method that will return a detector instance that allows detectors to read up to specified number of bytes when determining format match strength.

Parameters:

lookaheadBytes - Amount of look-ahead allowed

Returns:

Format detector instance with specified lookahead settings

findFormat

public DataFormatMatcher findFormat(InputStream in)
                             throws IOException

Method to call to find format that content (accessible via given InputStream) given has, as per configuration of this detector instance.

Parameters:

in - InputStream from which to read initial content

Returns:

Matcher object which contains result; never null, even in cases where no match (with specified minimal match strength) is found.

Throws:

IOException - for read I/O problems

findFormat

public DataFormatMatcher findFormat(byte[] fullInputData)
                             throws IOException

Method to call to find format that given content (full document) has, as per configuration of this detector instance.

Parameters:

fullInputData - Full contents to use for format detection

Returns:

Matcher object which contains result; never null, even in cases where no match (with specified minimal match strength) is found.

Throws:

IOException - for read I/O problems

findFormat

public DataFormatMatcher findFormat(byte[] fullInputData,
 int offset,
 int len)
                             throws IOException

Method to call to find format that given content (full document) has, as per configuration of this detector instance.

Parameters:

fullInputData - Full contents to use for format detection

offset - Offset of the first content byte

len - Length of content

Returns:

Matcher object which contains result; never null, even in cases where no match (with specified minimal match strength) is found.

Throws:

IOException - for read I/O problems

Since:

2.1

toString

public String toString()

Overrides:

toString in class Object