uk.ac.gla.terrier.structures
Class UTFLexiconInputStream

java.lang.Object
  uk.ac.gla.terrier.structures.LexiconInputStream
      uk.ac.gla.terrier.structures.UTFLexiconInputStream

All Implemented Interfaces:

java.lang.Iterable<java.lang.String>, Closeable

public class UTFLexiconInputStream
extends LexiconInputStream

This class implements an input stream for the lexicon structure.

Version:

$Revision: 1.16 $

Author:

Vassilis Plachouras, Craig Macdonald

Constructor Summary

UTFLexiconInputStream()
A default constructor.

UTFLexiconInputStream(java.io.DataInput in)
Read a lexicon from the specified input stream

UTFLexiconInputStream(java.io.File file)
A constructor given the filename.

UTFLexiconInputStream(java.lang.String filename)
A constructor given the filename.

UTFLexiconInputStream(java.lang.String path, java.lang.String prefix)

Method Summary

java.lang.String	getTerm() Returns the string representation of the term.
byte[]	getTermCharacters() Returns the bytes of the String.
int	numberOfEntries() Returns the number of entries in the lexicon file.
int	readNextEntry() Read the next lexicon entry, where the term is parsed as a string.
int	readNextEntryBytes() Read the next lexicon entry, where the term is saved as a byte array.

Methods inherited from class uk.ac.gla.terrier.structures.LexiconInputStream

close, getEndBitOffset, getEndOffset, getEntrySize, getNt, getNumberOfPointersRead, getNumberOfTermsRead, getNumberOfTokensRead, getStartBitOffset, getStartOffset, getTermId, getTF, iterator, print

Methods inherited from class java.lang.Object

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

Constructor Detail

UTFLexiconInputStream

public UTFLexiconInputStream()

A default constructor.

UTFLexiconInputStream

public UTFLexiconInputStream(java.lang.String filename)

A constructor given the filename.

Parameters:

filename - java.lang.String the name of the lexicon file.

UTFLexiconInputStream

public UTFLexiconInputStream(java.io.File file)

A constructor given the filename.

Parameters:

file - java.io.File the name of the lexicon file.

UTFLexiconInputStream

public UTFLexiconInputStream(java.lang.String path,
                             java.lang.String prefix)

UTFLexiconInputStream

public UTFLexiconInputStream(java.io.DataInput in)

Read a lexicon from the specified input stream

Method Detail

readNextEntry

public int readNextEntry()
                  throws java.io.IOException

Read the next lexicon entry, where the term is parsed as a string. This method does NOT work with getTermCharacters() - use readNextEntryBytes() iterator for that.

Overrides:

readNextEntry in class LexiconInputStream

Returns:

the number of bytes read if there is no error, otherwise returns -1 in case of EOF

Throws:

java.io.IOException - if an I/O error occurs

readNextEntryBytes

public int readNextEntryBytes()
                       throws java.io.IOException

Read the next lexicon entry, where the term is saved as a byte array. No attempt is made to parse the byte array and the padding bytes into a String. Use this method when you want to get the bytes of the string using getTermCharacters(). This method does NOT work with getTerm()

Overrides:

readNextEntryBytes in class LexiconInputStream

Returns:

the number of bytes read if there is no error, otherwise returns -1 in case of EOF

Throws:

java.io.IOException - if an I/O error occurs

numberOfEntries

public int numberOfEntries()

Returns the number of entries in the lexicon file.

Overrides:

numberOfEntries in class LexiconInputStream

getTerm

public java.lang.String getTerm()

Returns the string representation of the term.

Overrides:

getTerm in class LexiconInputStream

Returns:

the string representation of the already found term.

getTermCharacters

public byte[] getTermCharacters()

Returns the bytes of the String. Only valid is readNextEntryByte was used.

Overrides:

getTermCharacters in class LexiconInputStream

Returns:

the byte array holding the term's byte representation