Package org.apache.lucene.document

Class Field

java.lang.Object
org.apache.lucene.document.Field
All Implemented Interfaces:
IndexableField
Direct Known Subclasses:
BinaryDocValuesField, BinaryPoint, DoublePoint, DoubleRange, FeatureField, FloatPoint, FloatRange, InetAddressPoint, InetAddressRange, IntPoint, IntRange, KnnVectorField, LatLonDocValuesField, LatLonPoint, LongPoint, LongRange, NumericDocValuesField, ShapeField.Triangle, SortedDocValuesField, SortedNumericDocValuesField, SortedSetDocValuesField, StoredField, StringField, TextField, XYDocValuesField, XYPointField
public class Field extends Object implements IndexableField
Expert: directly create a field for a document. Most users should use one of the sugar subclasses:

A field is a section of a Document. Each field has three parts: name, type and value. Values may be text (String, Reader or pre-analyzed TokenStream), binary (byte[]), or numeric (a Number). Fields are optionally stored in the index, so that they may be returned with hits on the document.

NOTE: the field type is an IndexableFieldType. Making changes to the state of the IndexableFieldType will impact any Field it is used in. It is strongly recommended that no changes be made after Field instantiation.

  • Field Details

    • type

      protected final IndexableFieldType type
      Field's type

    • name

      protected final String name
      Field's name

    • fieldsData

      protected Object fieldsData
      Field's value

    • tokenStream

      protected TokenStream tokenStream
      Pre-analyzed tokenStream for indexed fields; this is separate from fieldsData because you are allowed to have both; eg maybe field has a String value but you customize how it's tokenized

  • Constructor Details

    • Field

      protected Field(String name, IndexableFieldType type)
      Expert: creates a field with no initial value. Intended only for custom Field subclasses.
      Parameters:
      name - field name
      type - field type
      Throws:
      IllegalArgumentException - if either the name or type is null.

    • Field

      public Field(String name, Reader reader, IndexableFieldType type)
      Create field with Reader value.
      Parameters:
      name - field name
      reader - reader value
      type - field type
      Throws:
      IllegalArgumentException - if either the name or type is null, or if the field's type is stored(), or if tokenized() is false.
      NullPointerException - if the reader is null

    • Field

      public Field(String name, TokenStream tokenStream, IndexableFieldType type)
      Create field with TokenStream value.
      Parameters:
      name - field name
      tokenStream - TokenStream value
      type - field type
      Throws:
      IllegalArgumentException - if either the name or type is null, or if the field's type is stored(), or if tokenized() is false, or if indexed() is false.
      NullPointerException - if the tokenStream is null

    • Field

      public Field(String name, byte[] value, IndexableFieldType type)
      Create field with binary value.

      NOTE: the provided byte[] is not copied so be sure not to change it until you're done with this field.

      Parameters:
      name - field name
      value - byte array pointing to binary content (not copied)
      type - field type
      Throws:
      IllegalArgumentException - if the field name, value or type is null, or the field's type is indexed().

    • Field

      public Field(String name, byte[] value, int offset, int length, IndexableFieldType type)
      Create field with binary value.

      NOTE: the provided byte[] is not copied so be sure not to change it until you're done with this field.

      Parameters:
      name - field name
      value - byte array pointing to binary content (not copied)
      offset - starting position of the byte array
      length - valid length of the byte array
      type - field type
      Throws:
      IllegalArgumentException - if the field name, value or type is null, or the field's type is indexed().

    • Field

      public Field(String name, BytesRef bytes, IndexableFieldType type)
      Create field with binary value.

      NOTE: the provided BytesRef is not copied so be sure not to change it until you're done with this field.

      Parameters:
      name - field name
      bytes - BytesRef pointing to binary content (not copied)
      type - field type
      Throws:
      IllegalArgumentException - if the field name, bytes or type is null, or the field's type is indexed().

    • Field

      public Field(String name, CharSequence value, IndexableFieldType type)
      Create field with String value.
      Parameters:
      name - field name
      value - string value
      type - field type
      Throws:
      IllegalArgumentException - if either the name, value or type is null, or if the field's type is neither indexed() nor stored(), or if indexed() is false but storeTermVectors() is true.

  • Method Details

    • stringValue

      public String stringValue()
      The value of the field as a String, or null. If null, the Reader value or binary value is used. Exactly one of stringValue(), readerValue(), and binaryValue() must be set.
      Specified by:
      stringValue in interface IndexableField

    • getCharSequenceValue

      public CharSequence getCharSequenceValue()
      Description copied from interface: IndexableField
      Non-null if this field has a string value
      Specified by:
      getCharSequenceValue in interface IndexableField

    • readerValue

      public Reader readerValue()
      The value of the field as a Reader, or null. If null, the String value or binary value is used. Exactly one of stringValue(), readerValue(), and binaryValue() must be set.
      Specified by:
      readerValue in interface IndexableField

    • tokenStreamValue

      public TokenStream tokenStreamValue()
      The TokenStream for this field to be used when indexing, or null. If null, the Reader value or String value is analyzed to produce the indexed tokens.

    • setStringValue

      public void setStringValue(String value)
      Expert: change the value of this field. This can be used during indexing to re-use a single Field instance to improve indexing speed by avoiding GC cost of new'ing and reclaiming Field instances. Typically a single Document instance is re-used as well. This helps most on small documents.

      Each Field instance should only be used once within a single Document instance. See ImproveIndexingSpeed for details.

    • setReaderValue

      public void setReaderValue(Reader value)
      Expert: change the value of this field. See setStringValue(String).

    • setBytesValue

      public void setBytesValue(byte[] value)
      Expert: change the value of this field. See setStringValue(String).

    • setBytesValue

      public void setBytesValue(BytesRef value)
      Expert: change the value of this field. See setStringValue(String).

      NOTE: the provided BytesRef is not copied so be sure not to change it until you're done with this field.

    • setByteValue

      public void setByteValue(byte value)
      Expert: change the value of this field. See setStringValue(String).

    • setShortValue

      public void setShortValue(short value)
      Expert: change the value of this field. See setStringValue(String).

    • setIntValue

      public void setIntValue(int value)
      Expert: change the value of this field. See setStringValue(String).

    • setLongValue

      public void setLongValue(long value)
      Expert: change the value of this field. See setStringValue(String).

    • setFloatValue

      public void setFloatValue(float value)
      Expert: change the value of this field. See setStringValue(String).

    • setDoubleValue

      public void setDoubleValue(double value)
      Expert: change the value of this field. See setStringValue(String).

    • setTokenStream

      public void setTokenStream(TokenStream tokenStream)
      Expert: sets the token stream to be used for indexing and causes isIndexed() and isTokenized() to return true. May be combined with stored values from stringValue() or binaryValue()

    • name

      public String name()
      Description copied from interface: IndexableField
      Field name
      Specified by:
      name in interface IndexableField

    • numericValue

      public Number numericValue()
      Description copied from interface: IndexableField
      Non-null if this field has a numeric value
      Specified by:
      numericValue in interface IndexableField

    • binaryValue

      public BytesRef binaryValue()
      Description copied from interface: IndexableField
      Non-null if this field has a binary value
      Specified by:
      binaryValue in interface IndexableField

    • toString

      public String toString()
      Prints a Field for human consumption.
      Overrides:
      toString in class Object

    • fieldType

      public IndexableFieldType fieldType()
      Returns the FieldType for this field.
      Specified by:
      fieldType in interface IndexableField

    • tokenStream

      public TokenStream tokenStream(Analyzer analyzer, TokenStream reuse)
      Description copied from interface: IndexableField
      Creates the TokenStream used for indexing this field. If appropriate, implementations should use the given Analyzer to create the TokenStreams.
      Specified by:
      tokenStream in interface IndexableField
      Parameters:
      analyzer - Analyzer that should be used to create the TokenStreams from
      reuse - TokenStream for a previous instance of this field name. This allows custom field types (like StringField and NumericField) that do not use the analyzer to still have good performance. Note: the passed-in type may be inappropriate, for example if you mix up different types of Fields for the same field name. So it's the responsibility of the implementation to check.
      Returns:
      TokenStream value for indexing the document. Should always return a non-null value if the field is to be indexed