Field (Lucene 4.0.0 API)

java.lang.Object
- org.apache.lucene.document.Field

All Implemented Interfaces:

IndexableField

Direct Known Subclasses:

ByteDocValuesField, DerefBytesDocValuesField, DoubleDocValuesField, DoubleField, FloatDocValuesField, FloatField, IntDocValuesField, IntField, LongDocValuesField, LongField, PackedLongDocValuesField, ShortDocValuesField, SortedBytesDocValuesField, StoredField, StraightBytesDocValuesField, StringField, TextField
```
public class Field
extends Object
implements IndexableField
```
Expert: directly create a field for a document. Most users should use one of the sugar subclasses: IntField, LongField, FloatField, DoubleField, ByteDocValuesField, ShortDocValuesField, IntDocValuesField, LongDocValuesField, PackedLongDocValuesField, FloatDocValuesField, DoubleDocValuesField, SortedBytesDocValuesField, DerefBytesDocValuesField, StraightBytesDocValuesField, StringField, TextField, StoredField.
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.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`Field.Index` Deprecated. This is here only to ease transition from the pre-4.0 APIs.
`static class`	`Field.Store` Specifies whether and how a field should be stored.
`static class`	`Field.TermVector` Deprecated. This is here only to ease transition from the pre-4.0 APIs.

Field Summary

Fields
Modifier and Type	Field and Description
`protected float`	`boost` Field's boost
`protected Object`	`fieldsData` Field's value
`protected String`	`name` Field's name
`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
`protected FieldType`	`type` Field's type

Constructor Summary

Constructors
Modifier	Constructor and Description
	`Field(String name, byte[] value)` Deprecated. Use `StoredField` instead.
	`Field(String name, byte[] value, FieldType type)` Create field with binary value.
	`Field(String name, byte[] value, int offset, int length)` Deprecated. Use `StoredField` instead.
	`Field(String name, byte[] value, int offset, int length, FieldType type)` Create field with binary value.
	`Field(String name, BytesRef bytes, FieldType type)` Create field with binary value.
`protected`	`Field(String name, FieldType type)` Expert: creates a field with no initial value.
	`Field(String name, Reader reader)` Deprecated. Use `TextField` instead.
	`Field(String name, Reader reader, Field.TermVector termVector)` Deprecated. Use `TextField` instead.
	`Field(String name, Reader reader, FieldType type)` Create field with Reader value.
	`Field(String name, String value, Field.Store store, Field.Index index)` Deprecated. Use `StringField`, `TextField` instead.
	`Field(String name, String value, Field.Store store, Field.Index index, Field.TermVector termVector)` Deprecated. Use `StringField`, `TextField` instead.
	`Field(String name, String value, FieldType type)` Create field with String value.
	`Field(String name, TokenStream tokenStream)` Deprecated. Use `TextField` instead
	`Field(String name, TokenStream tokenStream, Field.TermVector termVector)` Deprecated. Use `TextField` instead
	`Field(String name, TokenStream tokenStream, FieldType type)` Create field with TokenStream value.

Method Summary

Methods
Modifier and Type	Method and Description
`BytesRef`	`binaryValue()` Non-null if this field has a binary value
`float`	`boost()` Returns the field's index-time boost.
`FieldType`	`fieldType()` Returns the `FieldType` for this field.
`String`	`name()` Field name
`Number`	`numericValue()` Non-null if this field has a numeric value
`Reader`	`readerValue()` The value of the field as a Reader, or null.
`void`	`setBoost(float boost)` Sets the boost factor on this field.
`void`	`setBytesValue(byte[] value)` Expert: change the value of this field.
`void`	`setBytesValue(BytesRef value)` Expert: change the value of this field.
`void`	`setByteValue(byte value)` Expert: change the value of this field.
`void`	`setDoubleValue(double value)` Expert: change the value of this field.
`void`	`setFloatValue(float value)` Expert: change the value of this field.
`void`	`setIntValue(int value)` Expert: change the value of this field.
`void`	`setLongValue(long value)` Expert: change the value of this field.
`void`	`setReaderValue(Reader value)` Expert: change the value of this field.
`void`	`setShortValue(short value)` Expert: change the value of this field.
`void`	`setStringValue(String value)` Expert: change the value of this field.
`void`	`setTokenStream(TokenStream tokenStream)` Expert: sets the token stream to be used for indexing and causes isIndexed() and isTokenized() to return true.
`String`	`stringValue()` The value of the field as a String, or null.
`TokenStream`	`tokenStream(Analyzer analyzer)` Creates the TokenStream used for indexing this field.
`TokenStream`	`tokenStreamValue()` The TokenStream for this field to be used when indexing, or null.
`String`	`toString()` Prints a Field for human consumption.
`static FieldType`	`translateFieldType(Field.Store store, Field.Index index, Field.TermVector termVector)` Deprecated. This is here only to ease transition from the pre-4.0 APIs.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - type
```
protected final FieldType 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
  - boost
```
protected float boost
```
    Field's boost
    
    See Also:
    boost()
- Constructor Detail
  - Field
```
protected Field(String name,
     FieldType 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,
     FieldType 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,
     FieldType 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,
     FieldType 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 is null, or the field's type is indexed()
    
    NullPointerException - if the type is null
  - Field
```
public Field(String name,
     byte[] value,
     int offset,
     int length,
     FieldType 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 is null, or the field's type is indexed()
    
    NullPointerException - if the type is null
  - Field
```
public Field(String name,
     BytesRef bytes,
     FieldType 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 is null, or the field's type is indexed()
    
    NullPointerException - if the type is null
  - Field
```
public Field(String name,
     String value,
     FieldType type)
```
    Create field with String value.
    
    Parameters:
    name - field name
    value - string value
    type - field type
    
    Throws:
    
    IllegalArgumentException - if either the name or value is null, or if the field's type is neither indexed() nor stored(), or if indexed() is false but storeTermVectors() is true.
    
    NullPointerException - if the type is null
  - Field
```
@Deprecated
public Field(String name,
                String value,
                Field.Store store,
                Field.Index index)
```
    Deprecated. Use StringField, TextField instead.
    
    Create a field by specifying its name, value and how it will be saved in the index. Term vectors will not be stored in the index.
    
    Parameters:
    name - The name of the field
    value - The string to process
    store - Whether value should be stored in the index
    index - Whether the field should be indexed, and if so, if it should be tokenized before indexing
    
    Throws:
    
    NullPointerException - if name or value is null
    
    IllegalArgumentException - if the field is neither stored nor indexed
  - Field
```
@Deprecated
public Field(String name,
                String value,
                Field.Store store,
                Field.Index index,
                Field.TermVector termVector)
```
    Deprecated. Use StringField, TextField instead.
    
    Create a field by specifying its name, value and how it will be saved in the index.
    Parameters:
    name - The name of the field
    value - The string to process
    store - Whether value should be stored in the index
    index - Whether the field should be indexed, and if so, if it should be tokenized before indexing
    termVector - Whether term vector should be stored
    
    Throws:
    
    NullPointerException - if name or value is null
    IllegalArgumentException - in any of the following situations:
    
    the field is neither stored nor indexed
    
    the field is not indexed but termVector is TermVector.YES
  - Field
```
@Deprecated
public Field(String name,
                Reader reader)
```
    Deprecated. Use TextField instead.
    
    Create a tokenized and indexed field that is not stored. Term vectors will not be stored. The Reader is read only when the Document is added to the index, i.e. you may not close the Reader until IndexWriter.addDocument(java.lang.Iterable<? extends org.apache.lucene.index.IndexableField>) has been called.
    
    Parameters:
    name - The name of the field
    reader - The reader with the content
    
    Throws:
    
    NullPointerException - if name or reader is null
  - Field
```
@Deprecated
public Field(String name,
                Reader reader,
                Field.TermVector termVector)
```
    Deprecated. Use TextField instead.
    
    Create a tokenized and indexed field that is not stored, optionally with storing term vectors. The Reader is read only when the Document is added to the index, i.e. you may not close the Reader until IndexWriter.addDocument(java.lang.Iterable<? extends org.apache.lucene.index.IndexableField>) has been called.
    
    Parameters:
    name - The name of the field
    reader - The reader with the content
    termVector - Whether term vector should be stored
    
    Throws:
    
    NullPointerException - if name or reader is null
  - Field
```
@Deprecated
public Field(String name,
                TokenStream tokenStream)
```
    Deprecated. Use TextField instead
    
    Create a tokenized and indexed field that is not stored. Term vectors will not be stored. This is useful for pre-analyzed fields. The TokenStream is read only when the Document is added to the index, i.e. you may not close the TokenStream until IndexWriter.addDocument(java.lang.Iterable<? extends org.apache.lucene.index.IndexableField>) has been called.
    
    Parameters:
    name - The name of the field
    tokenStream - The TokenStream with the content
    
    Throws:
    
    NullPointerException - if name or tokenStream is null
  - Field
```
@Deprecated
public Field(String name,
                TokenStream tokenStream,
                Field.TermVector termVector)
```
    Deprecated. Use TextField instead
    
    Create a tokenized and indexed field that is not stored, optionally with storing term vectors. This is useful for pre-analyzed fields. The TokenStream is read only when the Document is added to the index, i.e. you may not close the TokenStream until IndexWriter.addDocument(java.lang.Iterable<? extends org.apache.lucene.index.IndexableField>) has been called.
    
    Parameters:
    name - The name of the field
    tokenStream - The TokenStream with the content
    termVector - Whether term vector should be stored
    
    Throws:
    
    NullPointerException - if name or tokenStream is null
  - Field
```
@Deprecated
public Field(String name,
                byte[] value)
```
    Deprecated. Use StoredField instead.
    
    Create a stored field with binary value. Optionally the value may be compressed.
    
    Parameters:
    name - The name of the field
    value - The binary value
  - Field
```
@Deprecated
public Field(String name,
                byte[] value,
                int offset,
                int length)
```
    Deprecated. Use StoredField instead.
    
    Create a stored field with binary value. Optionally the value may be compressed.
    
    Parameters:
    name - The name of the field
    value - The binary value
    offset - Starting offset in value where this Field's bytes are
    length - Number of bytes to use for this Field, starting at offset
- Method Detail
  - 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 getBinaryValue() must be set.
    
    Specified by:
    
    stringValue 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 getBinaryValue() 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 getBinaryValue()
  - name
```
public String name()
```
    Description copied from interface: IndexableField
    
    Field name
    
    Specified by:
    
    name in interface IndexableField
  - boost
```
public float boost()
```
    Returns the field's index-time boost.
    Only fields can have an index-time boost, if you want to simulate a "document boost", then you must pre-multiply it across all the relevant fields yourself.
    The boost is used to compute the norm factor for the field. By default, in the Similarity.computeNorm(FieldInvertState, Norm) method, the boost value is multiplied by the length normalization factor and then rounded by TFIDFSimilarity.encodeNormValue(float) before it is stored in the index. One should attempt to ensure that this product does not overflow the range of that encoding.
    It is illegal to return a boost other than 1.0f for a field that is not indexed (IndexableFieldType.indexed() is false) or omits normalization values (IndexableFieldType.omitNorms() returns true).
    The default value is 1.0f (no boost).
    
    Specified by:
    
    boost in interface IndexableField
    
    See Also:
    setBoost(float)
  - setBoost
```
public void setBoost(float boost)
```
    Sets the boost factor on this field.
    
    Throws:
    
    IllegalArgumentException - if this field is not indexed, or if it omits norms.
    See Also:
    boost()
  - 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 FieldType fieldType()
```
    Returns the FieldType for this field.
    
    Specified by:
    
    fieldType in interface IndexableField
  - tokenStream
```
public TokenStream tokenStream(Analyzer analyzer)
                        throws IOException
```
    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
    
    Returns:
    TokenStream value for indexing the document. Should always return a non-null value if the field is to be indexed
    
    Throws:
    
    IOException - Can be thrown while creating the TokenStream
  - translateFieldType
```
@Deprecated
public static final FieldType translateFieldType(Field.Store store,
                                      Field.Index index,
                                      Field.TermVector termVector)
```
    Deprecated. This is here only to ease transition from the pre-4.0 APIs.
    
    Translates the pre-4.0 enums for specifying how a field should be indexed into the 4.0 FieldType approach.

Class Field

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

type

name

fieldsData

tokenStream

boost

Constructor Detail

Field

Field

Field

Field

Field

Field

Field

Field

Field

Field

Field

Field

Field

Field

Field

Method Detail

stringValue

readerValue

tokenStreamValue

setStringValue

setReaderValue

setBytesValue

setBytesValue

setByteValue

setShortValue

setIntValue

setLongValue

setFloatValue

setDoubleValue

setTokenStream

name

boost

setBoost

numericValue

binaryValue

toString

fieldType

tokenStream

translateFieldType