Class TrimFilter

Trims leading and trailing whitespace from Tokens in the stream.

As of Lucene 4.4, this filter does not support updateOffsets=true anymore as it can lead to broken token streams.

Inheritance
object
AttributeSource
TokenStream
TokenFilter
TrimFilter
Implements
Inherited Members
TokenFilter.End()
TokenFilter.Reset()
TokenStream.Dispose()
AttributeSource.GetAttributeFactory()
AttributeSource.GetAttributeClassesEnumerator()
AttributeSource.GetAttributeImplsEnumerator()
AttributeSource.AddAttributeImpl(Attribute)
AttributeSource.AddAttribute<T>()
AttributeSource.HasAttributes
AttributeSource.HasAttribute<T>()
AttributeSource.GetAttribute<T>()
AttributeSource.ClearAttributes()
AttributeSource.CaptureState()
AttributeSource.RestoreState(AttributeSource.State)
AttributeSource.GetHashCode()
AttributeSource.ReflectWith(IAttributeReflector)
AttributeSource.CloneAttributes()
AttributeSource.CopyTo(AttributeSource)
AttributeSource.ToString()
Namespace: Lucene.Net.Analysis.Miscellaneous
Assembly: Lucene.Net.Analysis.Common.dll
Syntax
public sealed class TrimFilter : TokenFilter, IDisposable

Constructors

TrimFilter(LuceneVersion, TokenStream)

Create a new TrimFilter on top of in.

Declaration
public TrimFilter(LuceneVersion version, TokenStream @in)
Parameters
Type Name Description
LuceneVersion version
TokenStream in

TrimFilter(LuceneVersion, TokenStream, bool)

Create a new TrimFilter.

Declaration
[Obsolete("Offset updates are not supported anymore as of Lucene 4.4.")]
public TrimFilter(LuceneVersion version, TokenStream @in, bool updateOffsets)
Parameters
Type Name Description
LuceneVersion version

the Lucene match version
TokenStream in

the stream to consume
bool updateOffsets

whether to update offsets

Methods

IncrementToken()

Consumers (i.e., Lucene.Net.Index.IndexWriter) use this method to advance the stream to the next token. Implementing classes must implement this method and update the appropriate Lucene.Net.Util.IAttributes 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 Lucene.Net.Util.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 Lucene.Net.Util.AttributeSource.AddAttribute<T>() and Lucene.Net.Util.AttributeSource.GetAttribute<T>(), references to all Lucene.Net.Util.IAttributes 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 Lucene.Net.Analysis.TokenStream.IncrementToken().
Declaration
public override bool IncrementToken()
Returns
Type Description
bool

false for end of stream; true otherwise
Overrides
Lucene.Net.Analysis.TokenStream.IncrementToken()

Implements