uk.ac.gla.terrier.structures
Class UTFBlockLexiconInputStream

java.lang.Object
  uk.ac.gla.terrier.structures.LexiconInputStream
      uk.ac.gla.terrier.structures.BlockLexiconInputStream
          uk.ac.gla.terrier.structures.UTFBlockLexiconInputStream

All Implemented Interfaces:

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

public class UTFBlockLexiconInputStream
extends BlockLexiconInputStream

An input stream for accessing sequentially the entries of a block lexicon.

Version:

$Revision: 1.17 $

Author:

Douglas Johnson, Vassilis Plachouras

Constructor Summary

UTFBlockLexiconInputStream()
A default constructor.

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

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

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

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.
void	print() Prints out the contents of the lexicon file to check.
int	readNextEntry() Read the next lexicon entry.
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.BlockLexiconInputStream

getBlockFrequency

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

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

Methods inherited from class java.lang.Object

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

Constructor Detail

UTFBlockLexiconInputStream

public UTFBlockLexiconInputStream()

A default constructor.

UTFBlockLexiconInputStream

public UTFBlockLexiconInputStream(java.lang.String filename)

A constructor given the filename.

Parameters:

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

UTFBlockLexiconInputStream

public UTFBlockLexiconInputStream(java.io.File file)

A constructor given the filename.

Parameters:

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

UTFBlockLexiconInputStream

public UTFBlockLexiconInputStream(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.

Overrides:

readNextEntry in class BlockLexiconInputStream

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 BlockLexiconInputStream

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

print

public void print()

Prints out the contents of the lexicon file to check.

Overrides:

print in class BlockLexiconInputStream

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