Package org.apache.lucene.analysis.miscellaneous

Class WordDelimiterFilter

  • All Implemented Interfaces:
    java.io.Closeable, java.lang.AutoCloseable
    @Deprecated
public final class WordDelimiterFilter
extends TokenFilter
    Deprecated.
    Use WordDelimiterGraphFilter instead: it produces a correct token graph so that e.g. PhraseQuery works correctly when it's used in the search time analyzer.
    Splits words into subwords and performs optional transformations on subword groups. Words are split into subwords with the following rules:
    • split on intra-word delimiters (by default, all non alpha-numeric characters): "Wi-Fi" → "Wi", "Fi"
    • split on case transitions: "PowerShot" → "Power", "Shot"
    • split on letter-number transitions: "SD500" → "SD", "500"
    • leading and trailing intra-word delimiters on each subword are ignored: "//hello---there, 'dude'" → "hello", "there", "dude"
    • trailing "'s" are removed for each subword: "O'Neil's" → "O", "Neil"
      • Note: this step isn't performed in a separate filter because of possible subword combinations.
    The GENERATE... options affect how incoming tokens are broken into parts, and the various CATENATE_... parameters affect how those parts are combined.
    • If no CATENATE option is set, then no subword combinations are generated: "PowerShot" → 0:"Power", 1:"Shot" (0 and 1 are the token positions)
    • CATENATE_WORDS means that in addition to the subwords, maximum runs of non-numeric subwords are catenated and produced at the same position of the last subword in the run:
      • "PowerShot" → 0:"Power", 1:"Shot" 1:"PowerShot"
      • "A's+B's&C's" > 0:"A", 1:"B", 2:"C", 2:"ABC"
      • "Super-Duper-XL500-42-AutoCoder!" → 0:"Super", 1:"Duper", 2:"XL", 2:"SuperDuperXL", 3:"500" 4:"42", 5:"Auto", 6:"Coder", 6:"AutoCoder"
    • CATENATE_NUMBERS works like CATENATE_WORDS, but for adjacent digit sequences.
    • CATENATE_ALL smushes together all the token parts without distinguishing numbers and words.
    One use for WordDelimiterFilter is to help match words with different subword delimiters. For example, if the source text contained "wi-fi" one may want "wifi" "WiFi" "wi-fi" "wi+fi" queries to all match. One way of doing so is to specify CATENATE options in the analyzer used for indexing, and not in the analyzer used for querying. Given that the current StandardTokenizer immediately removes many intra-word delimiters, it is recommended that this filter be used after a tokenizer that does not do this (such as WhitespaceTokenizer).

    • Field Detail

      • GENERATE_WORD_PARTS

        public static final int GENERATE_WORD_PARTS
        Deprecated.
        Causes parts of words to be generated:

        "PowerShot" => "Power" "Shot"

        See Also:
        Constant Field Values

      • GENERATE_NUMBER_PARTS

        public static final int GENERATE_NUMBER_PARTS
        Deprecated.
        Causes number subwords to be generated:

        "500-42" => "500" "42"

        See Also:
        Constant Field Values

      • CATENATE_WORDS

        public static final int CATENATE_WORDS
        Deprecated.
        Causes maximum runs of word parts to be catenated:

        "wi-fi" => "wifi"

        See Also:
        Constant Field Values

      • CATENATE_NUMBERS

        public static final int CATENATE_NUMBERS
        Deprecated.
        Causes maximum runs of word parts to be catenated:

        "500-42" => "50042"

        See Also:
        Constant Field Values

      • CATENATE_ALL

        public static final int CATENATE_ALL
        Deprecated.
        Causes all subword parts to be catenated:

        "wi-fi-4000" => "wifi4000"

        See Also:
        Constant Field Values

      • PRESERVE_ORIGINAL

        public static final int PRESERVE_ORIGINAL
        Deprecated.
        Causes original words are preserved and added to the subword list (Defaults to false)

        "500-42" => "500" "42" "500-42"

        See Also:
        Constant Field Values

      • SPLIT_ON_CASE_CHANGE

        public static final int SPLIT_ON_CASE_CHANGE
        Deprecated.
        If not set, causes case changes to be ignored (subwords will only be generated given SUBWORD_DELIM tokens)
        See Also:
        Constant Field Values

      • SPLIT_ON_NUMERICS

        public static final int SPLIT_ON_NUMERICS
        Deprecated.
        If not set, causes numeric changes to be ignored (subwords will only be generated given SUBWORD_DELIM tokens).
        See Also:
        Constant Field Values

      • STEM_ENGLISH_POSSESSIVE

        public static final int STEM_ENGLISH_POSSESSIVE
        Deprecated.
        Causes trailing "'s" to be removed for each subword

        "O'Neil's" => "O", "Neil"

        See Also:
        Constant Field Values

      • protWords

        final CharArraySet protWords
        Deprecated.
        If not null is the set of tokens to protect from being delimited

      • flags

        private final int flags
        Deprecated.

      • offsetAttribute

        private final OffsetAttribute offsetAttribute
        Deprecated.

      • typeAttribute

        private final TypeAttribute typeAttribute
        Deprecated.

      • lastConcatCount

        private int lastConcatCount
        Deprecated.

      • accumPosInc

        private int accumPosInc
        Deprecated.

      • savedBuffer

        private char[] savedBuffer
        Deprecated.

      • savedStartOffset

        private int savedStartOffset
        Deprecated.

      • savedEndOffset

        private int savedEndOffset
        Deprecated.

      • savedType

        private java.lang.String savedType
        Deprecated.

      • hasSavedState

        private boolean hasSavedState
        Deprecated.

      • hasIllegalOffsets

        private boolean hasIllegalOffsets
        Deprecated.

      • hasOutputToken

        private boolean hasOutputToken
        Deprecated.

      • hasOutputFollowingOriginal

        private boolean hasOutputFollowingOriginal
        Deprecated.

      • startOff

        private int[] startOff
        Deprecated.

      • posInc

        private int[] posInc
        Deprecated.

      • bufferedLen

        private int bufferedLen
        Deprecated.

      • bufferedPos

        private int bufferedPos
        Deprecated.

      • first

        private boolean first
        Deprecated.

    • Constructor Detail

      • WordDelimiterFilter

        public WordDelimiterFilter​(TokenStream in,
                           byte[] charTypeTable,
                           int configurationFlags,
                           CharArraySet protWords)
        Deprecated.
        Creates a new WordDelimiterFilter
        Parameters:
        in - TokenStream to be filtered
        charTypeTable - table containing character types
        configurationFlags - Flags configuring the filter
        protWords - If not null is the set of tokens to protect from being delimited

      • WordDelimiterFilter

        public WordDelimiterFilter​(TokenStream in,
                           int configurationFlags,
                           CharArraySet protWords)
        Deprecated.
        Creates a new WordDelimiterFilter using WordDelimiterIterator.DEFAULT_WORD_DELIM_TABLE as its charTypeTable
        Parameters:
        in - TokenStream to be filtered
        configurationFlags - Flags configuring the filter
        protWords - If not null is the set of tokens to protect from being delimited

    • Method Detail

      • incrementToken

        public boolean incrementToken()
                       throws java.io.IOException
        Deprecated.
        Description copied from class: TokenStream
        Consumers (i.e., IndexWriter) use this method to advance the stream to the next token. Implementing classes must implement this method and update the appropriate AttributeImpls with the attributes of the next token.

        The producer must make no assumptions about the attributes after the method has been returned: the caller may arbitrarily change it. If the producer needs to preserve the state for subsequent calls, it can use AttributeSource.captureState() to create a copy of the current attribute state.

        This method is called for every token of a document, so an efficient implementation is crucial for good performance. To avoid calls to AttributeSource.addAttribute(Class) and AttributeSource.getAttribute(Class), references to all AttributeImpls that this stream uses should be retrieved during instantiation.

        To ensure that filters and consumers know which attributes are available, the attributes must be added during instantiation. Filters and consumers are not required to check for availability of attributes in TokenStream.incrementToken().

        Specified by:
        incrementToken in class TokenStream
        Returns:
        false for end of stream; true otherwise
        Throws:
        java.io.IOException

      • reset

        public void reset()
           throws java.io.IOException
        Deprecated.
        Description copied from class: TokenFilter
        This method is called by a consumer before it begins consumption using TokenStream.incrementToken().

        Resets this stream to a clean state. Stateful implementations must implement this method so that they can be reused, just as if they had been created fresh.

        If you override this method, always call super.reset(), otherwise some internal state will not be correctly reset (e.g., Tokenizer will throw IllegalStateException on further usage).

        NOTE: The default implementation chains the call to the input TokenStream, so be sure to call super.reset() when overriding this method.

        Overrides:
        reset in class TokenFilter
        Throws:
        java.io.IOException

      • buffer

        private void buffer()
        Deprecated.

      • saveState

        private void saveState()
        Deprecated.
        Saves the existing attribute states

      • flushConcatenation

        private boolean flushConcatenation​(WordDelimiterFilter.WordDelimiterConcatenation concatenation)
        Deprecated.
        Flushes the given WordDelimiterConcatenation by either writing its concat and then clearing, or just clearing.
        Parameters:
        concatenation - WordDelimiterConcatenation that will be flushed
        Returns:
        true if the concatenation was written before it was cleared, false otherwise

      • shouldConcatenate

        private boolean shouldConcatenate​(int wordType)
        Deprecated.
        Determines whether to concatenate a word or number if the current word is the given type
        Parameters:
        wordType - Type of the current word used to determine if it should be concatenated
        Returns:
        true if concatenation should occur, false otherwise

      • shouldGenerateParts

        private boolean shouldGenerateParts​(int wordType)
        Deprecated.
        Determines whether a word/number part should be generated for a word of the given type
        Parameters:
        wordType - Type of the word used to determine if a word/number part should be generated
        Returns:
        true if a word/number part should be generated, false otherwise

      • concatenate

        private void concatenate​(WordDelimiterFilter.WordDelimiterConcatenation concatenation)
        Deprecated.
        Concatenates the saved buffer to the given WordDelimiterConcatenation
        Parameters:
        concatenation - WordDelimiterConcatenation to concatenate the buffer to

      • generatePart

        private void generatePart​(boolean isSingleWord)
        Deprecated.
        Generates a word/number part, updating the appropriate attributes
        Parameters:
        isSingleWord - true if the generation is occurring from a single word, false otherwise

      • position

        private int position​(boolean inject)
        Deprecated.
        Get the position increment gap for a subword or concatenation
        Parameters:
        inject - true if this token wants to be injected
        Returns:
        position increment gap

      • isAlpha

        static boolean isAlpha​(int type)
        Deprecated.
        Checks if the given word type includes ALPHA
        Parameters:
        type - Word type to check
        Returns:
        true if the type contains ALPHA, false otherwise

      • isDigit

        static boolean isDigit​(int type)
        Deprecated.
        Checks if the given word type includes DIGIT
        Parameters:
        type - Word type to check
        Returns:
        true if the type contains DIGIT, false otherwise

      • isSubwordDelim

        static boolean isSubwordDelim​(int type)
        Deprecated.
        Checks if the given word type includes SUBWORD_DELIM
        Parameters:
        type - Word type to check
        Returns:
        true if the type contains SUBWORD_DELIM, false otherwise

      • isUpper

        static boolean isUpper​(int type)
        Deprecated.
        Checks if the given word type includes UPPER
        Parameters:
        type - Word type to check
        Returns:
        true if the type contains UPPER, false otherwise

      • has

        private boolean has​(int flag)
        Deprecated.
        Determines whether the given flag is set
        Parameters:
        flag - Flag to see if set
        Returns:
        true if flag is set