com.aliasi.tokenizer
Class LineTokenizerFactory

java.lang.Object
  com.aliasi.tokenizer.RegExTokenizerFactory
      com.aliasi.tokenizer.LineTokenizerFactory

All Implemented Interfaces:

TokenizerFactory, Serializable

public class LineTokenizerFactory
extends RegExTokenizerFactory

A LineTokenizerFactory treats each line of an input as a token. Whitespaces separating lines are simply newlines. This is useful for decoders that work at the line level.

Line terminators are as defined in Pattern, and include all of the Windows, Unix, and Macintosh standards, as well as some unicode extensions.

Whitespaces will be either empty strings or strings representing one or more newlines.

Tokens may consist entirely of whitespace characters if whitespace is the only thing on a line. But tokens will never contain sequences representing newlines. Tokens will alwyas consist of at least one character.

Examples

Input String	Tokens	Whitespaces
""	{}	{ "" }
"abc"	{ "abc" }	{ "", "" }
"abc\ndef"	{ "abc", "def" }	{ "", "\n", "" }
"abc\r\ndef"	{ "abc", "def" }	{ "", "\r\n", "" }
"abc\r\ndef"	{ "abc", "def" }	{ "", "\r\n", "" }
" abc\n def \n"	{ " abc", " def " }	{ "", "\n", "\n" }
" \n"	{ " " }	{ "", "\n" }

Thread Safety

Line tokenizer factories are completely thread safe.

Serialization

A line tokenizer factory may be serialized. Upon deserialization, the resulting class will be the singleton item INSTANCE.

Implementation Note

This tokenizer factory is nothing more than a convenience wrapper around a very simple RegExTokenizerFactory, with the simplest possible regular expression:

      RegExTokenizerFactory(".+")

Because the regular expression tokenizer factory takes the default regular expression flags (see Pattern), the period (.) matches any character except a newline.

Since:

LingPipe3.2

Version:

4.0.0

Author:

Bob Carpenter

See Also:

Serialized Form

Field Summary

static LineTokenizerFactory

INSTANCE A reusable instance of this class.

Method Summary

String

toString() Returns a string representation of this factory, consisting of its name.

Methods inherited from class com.aliasi.tokenizer.RegExTokenizerFactory

pattern, tokenizer

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static final LineTokenizerFactory INSTANCE

A reusable instance of this class. Because line tokenizer factories are thread safe, this instance may be used everywhere.

Method Detail

toString

public String toString()

Returns a string representation of this factory, consisting of its name.

Overrides:

toString in class RegExTokenizerFactory

Returns:

The name of this class.