org.apache.lucene.document
Class Document
java.lang.Object
org.apache.lucene.document.Document
- java.io.Serializable
public final class Document
extends java.lang.Object
implements java.io.Serializable
Documents are the unit of indexing and search.
A Document is a set of fields. Each field has a name and a textual value.
A field may be
stored
with the document, in which
case it is returned with search hits on the document. Thus each document
should typically contain one or more stored fields which uniquely identify
it.
Note that fields which are
not stored
are
not available in documents retrieved from the index, e.g. with
Hits.doc(int)
,
Searcher.doc(int)
or
IndexReader.document(int)
.
Document() - Constructs a new document with no fields.
|
void | add(Field field) - Adds a field to a document.
|
Enumeration | fields() - Returns an Enumeration of all the fields in a document.
|
String | get(String name) - Returns the string value of the field with the given name if any exist in
this document, or null.
|
float | getBoost() - Returns the boost factor for hits on any field of this document.
|
Field | getField(String name) - Returns a field with the given name if any exist in this document, or
null.
|
Field[] | getFields(String name) - Returns an array of
Field s with the given name.
|
String[] | getValues(String name) - Returns an array of values of the field specified as the method parameter.
|
void | removeField(String name) - Removes field with the specified name from the document.
|
void | removeFields(String name) - Removes all fields with the given name from the document.
|
void | setBoost(float boost) - Sets a boost factor for hits on any field of this document.
|
String | toString() - Prints the fields of a document for human consumption.
|
Document
public Document()
Constructs a new document with no fields.
add
public final void add(Field field)
Adds a field to a document. Several fields may be added with
the same name. In this case, if the fields are indexed, their text is
treated as though appended for the purposes of search.
Note that add like the removeField(s) methods only makes sense
prior to adding a document to an index. These methods cannot
be used to change the content of an existing index! In order to achieve this,
a document has to be deleted from an index and a new changed version of that
document has to be added.
fields
public final Enumeration fields()
Returns an Enumeration of all the fields in a document.
get
public final String get(String name)
Returns the string value of the field with the given name if any exist in
this document, or null. If multiple fields exist with this name, this
method returns the first value added.
getBoost
public float getBoost()
Returns the boost factor for hits on any field of this document.
The default value is 1.0.
Note: This value is not stored directly with the document in the index.
Documents returned from
IndexReader.document(int)
and
Hits.doc(int)
may thus not have the same value present as when
this document was indexed.
getField
public final Field getField(String name)
Returns a field with the given name if any exist in this document, or
null. If multiple fields exists with this name, this method returns the
first value added.
getFields
public final Field[] getFields(String name)
Returns an array of
Field
s with the given name.
This method can return
null
.
name
- the name of the field
getValues
public final String[] getValues(String name)
Returns an array of values of the field specified as the method parameter.
This method can return null
.
name
- the name of the field
- a
String[]
of field values
removeField
public final void removeField(String name)
Removes field with the specified name from the document.
If multiple fields exist with this name, this method removes the first field that has been added.
If there is no field with the specified name, the document remains unchanged.
Note that the removeField(s) methods like the add method only make sense
prior to adding a document to an index. These methods cannot
be used to change the content of an existing index! In order to achieve this,
a document has to be deleted from an index and a new changed version of that
document has to be added.
removeFields
public final void removeFields(String name)
Removes all fields with the given name from the document.
If there is no field with the specified name, the document remains unchanged.
Note that the removeField(s) methods like the add method only make sense
prior to adding a document to an index. These methods cannot
be used to change the content of an existing index! In order to achieve this,
a document has to be deleted from an index and a new changed version of that
document has to be added.
setBoost
public void setBoost(float boost)
Sets a boost factor for hits on any field of this document. This value
will be multiplied into the score of all hits on this document.
Values are multiplied into the value of
Field.getBoost()
of
each field in this document. Thus, this method in effect sets a default
boost for the fields of this document.
toString
public final String toString()
Prints the fields of a document for human consumption.
Copyright © 2000-2006 Apache Software Foundation. All Rights Reserved.