Document
for indexing and searching.See: Description
Interface | Description |
---|---|
Fieldable |
Synonymous with
Field . |
FieldSelector |
Similar to a
FileFilter , the FieldSelector allows one to make decisions about
what Fields get loaded on a Document by IndexReader.document(int,org.apache.lucene.document.FieldSelector) |
Class | Description |
---|---|
AbstractField |
Base class for Field implementations
|
CompressionTools |
Simple utility class providing static methods to
compress and decompress binary data for stored fields.
|
DateField | Deprecated
If you build a new index, use
DateTools or
NumericField instead. |
DateTools |
Provides support for converting dates to strings and vice-versa.
|
Document |
Documents are the unit of indexing and search.
|
Field |
A field is a section of a Document.
|
LoadFirstFieldSelector |
Load the First field and break.
|
MapFieldSelector |
A
FieldSelector based on a Map of field names to FieldSelectorResult s |
NumberTools | Deprecated
For new indexes use
NumericUtils instead, which
provides a sortable binary representation (prefix encoded) of numeric
values. |
NumericField |
This class provides a
Field that enables indexing
of numeric values for efficient range filtering and
sorting. |
SetBasedFieldSelector |
Declare what fields to load normally and what fields to load lazily
|
Enum | Description |
---|---|
DateTools.Resolution |
Specifies the time granularity.
|
Field.Index |
Specifies whether and how a field should be indexed.
|
Field.Store |
Specifies whether and how a field should be stored.
|
Field.TermVector |
Specifies whether and how a field should have term vectors.
|
FieldSelectorResult |
Provides information about what should be done with this Field
|
NumericField.DataType |
Data type of the value in
NumericField . |
The logical representation of a Document
for indexing and searching.
The document package provides the user level logical representation of content to be indexed and searched. The
package also provides utilities for working with Document
s and Fieldable
s.
A Document
is a collection of Fieldable
s. A
Fieldable
is a logical representation of a user's content that needs to be indexed or stored.
Fieldable
s have a number of properties that tell Lucene how to treat the content (like indexed, tokenized,
stored, etc.) See the Field
implementation of Fieldable
for specifics on these properties.
Note: it is common to refer to Document
s having Field
s, even though technically they have
Fieldable
s.
First and foremost, a Document
is something created by the user application. It is your job
to create Documents based on the content of the files you are working with in your application (Word, txt, PDF, Excel or any other format.)
How this is done is completely up to you. That being said, there are many tools available in other projects that can make
the process of taking a file and converting it into a Lucene Document
. To see an example of this,
take a look at the Lucene demo and the associated source code
for extracting content from HTML.
The DateTools
is a utility class to make dates and times searchable
(remember, Lucene only searches text). NumericField
is a special helper class
to simplify indexing of numeric values (and also dates) for fast range range queries with NumericRangeQuery
(using a special sortable string representation of numeric values).
The FieldSelector
class provides a mechanism to tell Lucene how to load Documents from
storage. If no FieldSelector is used, all Fieldables on a Document will be loaded. As an example of the FieldSelector usage, consider
the common use case of
displaying search results on a web page and then having users click through to see the full document. In this scenario, it is often
the case that there are many small fields and one or two large fields (containing the contents of the original file). Before the FieldSelector,
the full Document had to be loaded, including the large fields, in order to display the results. Now, using the FieldSelector, one
can FieldSelectorResult.LAZY_LOAD
the large fields, thus only loading the large fields
when a user clicks on the actual link to view the original content.