Package org.apache.lucene.search

Class FieldCacheRangeFilter<T>

  • public abstract class FieldCacheRangeFilter<T>
extends Filter
    A range filter built on top of a cached single term field (in FieldCache).

    FieldCacheRangeFilter builds a single cache for the field the first time it is used. Each subsequent FieldCacheRangeFilter on the same field then reuses this cache, even if the range itself changes.

    This means that FieldCacheRangeFilter is much faster (sometimes more than 100x as fast) as building a TermRangeFilter, if using a newStringRange(java.lang.String, java.lang.String, java.lang.String, boolean, boolean). However, if the range never changes it is slower (around 2x as slow) than building a CachingWrapperFilter on top of a single TermRangeFilter. For numeric data types, this filter may be significantly faster than NumericRangeFilter. Furthermore, it does not need the numeric values encoded by IntField, FloatField, LongField or DoubleField. But it has the problem that it only works with exact one value/document (see below).

    As with all FieldCache based functionality, FieldCacheRangeFilter is only valid for fields which exact one term for each document (except for newStringRange(java.lang.String, java.lang.String, java.lang.String, boolean, boolean) where 0 terms are also allowed). Due to a restriction of FieldCache, for numeric ranges all terms that do not have a numeric value, 0 is assumed.

    Thus it works on dates, prices and other single value fields but will not work on regular text fields. It is preferable to use a NOT_ANALYZED field to ensure that there is only a single term.

    This class does not have an constructor, use one of the static factory methods available, that create a correct instance for different data types supported by FieldCache.

    • Method Detail

      • getDocIdSet

        public abstract DocIdSet getDocIdSet​(AtomicReaderContext context,
                                     Bits acceptDocs)
                              throws java.io.IOException
        This method is implemented for each data type
        Specified by:
        getDocIdSet in class Filter
        Parameters:
        context - a AtomicReaderContext instance opened on the index currently searched on. Note, it is likely that the provided reader info does not represent the whole underlying index i.e. if the index has more than one segment the given reader only represents a single segment. The provided context is always an atomic context, so you can call AtomicReader.fields() on the context's reader, for example.
        acceptDocs - Bits that represent the allowable docs to match (typically deleted docs but possibly filtering other documents)
        Returns:
        a DocIdSet that provides the documents which should be permitted or prohibited in search results. NOTE: null should be returned if the filter doesn't accept any documents otherwise internal optimization might not apply in the case an empty DocIdSet is returned.
        Throws:
        java.io.IOException

      • newByteRange

        @Deprecated
public static FieldCacheRangeFilter<java.lang.Byte> newByteRange​(java.lang.String field,
                                                                 java.lang.Byte lowerVal,
                                                                 java.lang.Byte upperVal,
                                                                 boolean includeLower,
                                                                 boolean includeUpper)
        Deprecated.
        Creates a numeric range filter using FieldCache.getBytes(AtomicReader,String,boolean). This works with all byte fields containing exactly one numeric term in the field. The range can be half-open by setting one of the values to null.

      • newShortRange

        @Deprecated
public static FieldCacheRangeFilter<java.lang.Short> newShortRange​(java.lang.String field,
                                                                   java.lang.Short lowerVal,
                                                                   java.lang.Short upperVal,
                                                                   boolean includeLower,
                                                                   boolean includeUpper)
        Deprecated.
        Creates a numeric range filter using FieldCache.getShorts(AtomicReader,String,boolean). This works with all short fields containing exactly one numeric term in the field. The range can be half-open by setting one of the values to null.

      • newIntRange

        public static FieldCacheRangeFilter<java.lang.Integer> newIntRange​(java.lang.String field,
                                                                   java.lang.Integer lowerVal,
                                                                   java.lang.Integer upperVal,
                                                                   boolean includeLower,
                                                                   boolean includeUpper)
        Creates a numeric range filter using FieldCache.getInts(AtomicReader,String,boolean). This works with all int fields containing exactly one numeric term in the field. The range can be half-open by setting one of the values to null.

      • newLongRange

        public static FieldCacheRangeFilter<java.lang.Long> newLongRange​(java.lang.String field,
                                                                 java.lang.Long lowerVal,
                                                                 java.lang.Long upperVal,
                                                                 boolean includeLower,
                                                                 boolean includeUpper)
        Creates a numeric range filter using FieldCache.getLongs(AtomicReader,String,boolean). This works with all long fields containing exactly one numeric term in the field. The range can be half-open by setting one of the values to null.

      • newFloatRange

        public static FieldCacheRangeFilter<java.lang.Float> newFloatRange​(java.lang.String field,
                                                                   java.lang.Float lowerVal,
                                                                   java.lang.Float upperVal,
                                                                   boolean includeLower,
                                                                   boolean includeUpper)
        Creates a numeric range filter using FieldCache.getFloats(AtomicReader,String,boolean). This works with all float fields containing exactly one numeric term in the field. The range can be half-open by setting one of the values to null.

      • newDoubleRange

        public static FieldCacheRangeFilter<java.lang.Double> newDoubleRange​(java.lang.String field,
                                                                     java.lang.Double lowerVal,
                                                                     java.lang.Double upperVal,
                                                                     boolean includeLower,
                                                                     boolean includeUpper)
        Creates a numeric range filter using FieldCache.getDoubles(AtomicReader,String,boolean). This works with all double fields containing exactly one numeric term in the field. The range can be half-open by setting one of the values to null.

      • toString

        public final java.lang.String toString()
        Overrides:
        toString in class java.lang.Object

      • equals

        public final boolean equals​(java.lang.Object o)
        Overrides:
        equals in class java.lang.Object

      • hashCode

        public final int hashCode()
        Overrides:
        hashCode in class java.lang.Object

      • getField

        public java.lang.String getField()
        Returns the field name for this filter

      • includesLower

        public boolean includesLower()
        Returns true if the lower endpoint is inclusive

      • includesUpper

        public boolean includesUpper()
        Returns true if the upper endpoint is inclusive

      • getLowerVal

        public T getLowerVal()
        Returns the lower value of this range filter

      • getUpperVal

        public T getUpperVal()
        Returns the upper value of this range filter

      • getParser

        public FieldCache.Parser getParser()
        Returns the current numeric parser (null for T is String}