|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Object org.apache.lucene.util.AttributeSource org.apache.lucene.analysis.TokenStream org.apache.lucene.analysis.TokenFilter org.apache.lucene.analysis.reverse.ReverseStringFilter
public final class ReverseStringFilter
Reverse token string, for example "country" => "yrtnuoc".
If marker
is supplied, then tokens will be also prepended by
that character. For example, with a marker of \u0001, "country" =>
"\u0001yrtnuoc". This is useful when implementing efficient leading
wildcards search.
Nested Class Summary |
---|
Nested classes/interfaces inherited from class org.apache.lucene.util.AttributeSource |
---|
AttributeSource.AttributeFactory, AttributeSource.State |
Field Summary | |
---|---|
static char |
INFORMATION_SEPARATOR_MARKER
Example marker character: U+001F (INFORMATION SEPARATOR ONE) |
static char |
PUA_EC00_MARKER
Example marker character: U+EC00 (PRIVATE USE AREA: EC00) |
static char |
RTL_DIRECTION_MARKER
Example marker character: U+200F (RIGHT-TO-LEFT MARK) |
static char |
START_OF_HEADING_MARKER
Example marker character: U+0001 (START OF HEADING) |
Fields inherited from class org.apache.lucene.analysis.TokenFilter |
---|
input |
Constructor Summary | |
---|---|
ReverseStringFilter(TokenStream in)
Create a new ReverseStringFilter that reverses all tokens in the supplied TokenStream . |
|
ReverseStringFilter(TokenStream in,
char marker)
Create a new ReverseStringFilter that reverses and marks all tokens in the supplied TokenStream . |
Method Summary | |
---|---|
boolean |
incrementToken()
Consumers (i.e., IndexWriter ) use this method to advance the stream to
the next token. |
static void |
reverse(char[] buffer)
|
static void |
reverse(char[] buffer,
int len)
|
static void |
reverse(char[] buffer,
int start,
int len)
|
static String |
reverse(String input)
|
Methods inherited from class org.apache.lucene.analysis.TokenFilter |
---|
close, end, reset |
Methods inherited from class org.apache.lucene.util.AttributeSource |
---|
addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, restoreState, toString |
Methods inherited from class java.lang.Object |
---|
clone, finalize, getClass, notify, notifyAll, wait, wait, wait |
Field Detail |
---|
public static final char START_OF_HEADING_MARKER
public static final char INFORMATION_SEPARATOR_MARKER
public static final char PUA_EC00_MARKER
public static final char RTL_DIRECTION_MARKER
Constructor Detail |
---|
public ReverseStringFilter(TokenStream in)
TokenStream
.
The reversed tokens will not be marked.
in
- TokenStream
to filterpublic ReverseStringFilter(TokenStream in, char marker)
TokenStream
.
The reversed tokens will be prepended (marked) by the marker
character.
in
- TokenStream
to filtermarker
- A character used to mark reversed tokensMethod Detail |
---|
public boolean incrementToken() throws IOException
TokenStream
IndexWriter
) use this method to advance the stream to
the next token. Implementing classes must implement this method and update
the appropriate AttributeImpl
s with the attributes of the next
token.
The producer must make no assumptions about the attributes after the method
has been returned: the caller may arbitrarily change it. If the producer
needs to preserve the state for subsequent calls, it can use
AttributeSource.captureState()
to create a copy of the current attribute state.
This method is called for every token of a document, so an efficient
implementation is crucial for good performance. To avoid calls to
AttributeSource.addAttribute(Class)
and AttributeSource.getAttribute(Class)
,
references to all AttributeImpl
s that this stream uses should be
retrieved during instantiation.
To ensure that filters and consumers know which attributes are available,
the attributes must be added during instantiation. Filters and consumers
are not required to check for availability of attributes in
TokenStream.incrementToken()
.
incrementToken
in class TokenStream
IOException
public static String reverse(String input)
public static void reverse(char[] buffer)
public static void reverse(char[] buffer, int len)
public static void reverse(char[] buffer, int start, int len)
|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |