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org.apache.lucene.document
public final class: Field [javadoc | source]
java.lang.Object
   org.apache.lucene.document.AbstractField
      org.apache.lucene.document.Field

All Implemented Interfaces:
    Fieldable, java$io$Serializable

A field is a section of a Document. Each field has two parts, a name and a value. Values may be free text, provided as a String or as a Reader, or they may be atomic keywords, which are not further processed. Such keywords may be used to represent dates, urls, etc. Fields are optionally stored in the index, so that they may be returned with hits on the document.
Nested Class Summary:
public static enum class  Field.Store  Specifies whether and how a field should be stored. 
public static enum class  Field.Index  Specifies whether and how a field should be indexed. 
public static enum class  Field.TermVector  Specifies whether and how a field should have term vectors. 
Fields inherited from org.apache.lucene.document.AbstractField:
name,  storeTermVector,  storeOffsetWithTermVector,  storePositionWithTermVector,  omitNorms,  isStored,  isIndexed,  isTokenized,  isBinary,  lazy,  omitTermFreqAndPositions,  boost,  fieldsData,  tokenStream,  binaryLength,  binaryOffset
Constructor:
 public Field(String name,
    Reader reader) 
    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(Document) has been called.
    Parameters:
    name - The name of the field
    reader - The reader with the content
    Throws:
    NullPointerException - if name or reader is null
 public Field(String name,
    TokenStream tokenStream) 
    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(Document) has been called.
    Parameters:
    name - The name of the field
    tokenStream - The TokenStream with the content
    Throws:
    NullPointerException - if name or tokenStream is null
 public Field(String name,
    Reader reader,
    TermVector termVector) 
    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(Document) 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
 public Field(String name,
    TokenStream tokenStream,
    TermVector termVector) 
    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(Document) 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
 public Field(String name,
    byte[] value,
    Store store) 
    Create a stored field with binary value. Optionally the value may be compressed.
    Parameters:
    name - The name of the field
    value - The binary value
    store - How value should be stored (compressed or not)
    Throws:
    IllegalArgumentException - if store is Store.NO
 public Field(String name,
    String value,
    Store store,
    Index index) 
    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
 public Field(String name,
    String value,
    Store store,
    Index index,
    TermVector termVector) 
    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

 public Field(String name,
    byte[] value,
    int offset,
    int length,
    Store store) 
    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
    store - How value should be stored (compressed or not)
    Throws:
    IllegalArgumentException - if store is Store.NO
 public Field(String name,
    boolean internName,
    String value,
    Store store,
    Index index,
    TermVector termVector) 
    Create a field by specifying its name, value and how it will be saved in the index.
    Parameters:
    name - The name of the field
    internName - Whether to .intern() name or not
    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

Method from org.apache.lucene.document.Field Summary:
readerValue,   setTokenStream,   setValue,   setValue,   setValue,   setValue,   stringValue,   tokenStreamValue
Methods from org.apache.lucene.document.AbstractField:
getBinaryLength,   getBinaryOffset,   getBinaryValue,   getBinaryValue,   getBoost,   getOmitNorms,   getOmitTermFreqAndPositions,   isBinary,   isIndexed,   isLazy,   isStoreOffsetWithTermVector,   isStorePositionWithTermVector,   isStored,   isTermVectorStored,   isTokenized,   name,   setBoost,   setOmitNorms,   setOmitTermFreqAndPositions,   setStoreTermVector,   toString
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from org.apache.lucene.document.Field Detail:
 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.
 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()
 public  void setValue(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.

 public  void setValue(Reader value) 
 public  void setValue(byte[] value) 
 public  void setValue(byte[] value,
    int offset,
    int length) 
 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.
 public TokenStream tokenStreamValue() 
    The TokesStream 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.