org.apache.lucene.analysis

## Class Tokenizer

- java.lang.Object
- - org.apache.lucene.util.AttributeSource
  - - org.apache.lucene.analysis.TokenStream
    - - org.apache.lucene.analysis.Tokenizer

- All Implemented Interfaces:
    Closeable, AutoCloseable
  Direct Known Subclasses:
    StandardTokenizer

      public abstract class Tokenizer
      extends TokenStream

  A Tokenizer is a TokenStream whose input is a Reader.

  This is an abstract class; subclasses must override `TokenStream.incrementToken()`

  NOTE: Subclasses overriding `TokenStream.incrementToken()` must call `AttributeSource.clearAttributes()` before setting attributes.

- - ### Nested Class Summary

    - ### Nested classes/interfaces inherited from class org.apache.lucene.util.AttributeSource

      `AttributeSource.State`

  - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `protected Reader` | `input` The text source for this Tokenizer.

    - ### Fields inherited from class org.apache.lucene.analysis.TokenStream

      `DEFAULT_TOKEN_ATTRIBUTE_FACTORY`

  - ### Constructor Summary

    Constructors
    Modifier | Constructor and Description
    --- | ---
    `protected` | `Tokenizer()` Construct a tokenizer with no input, awaiting a call to `setReader(java.io.Reader)` to provide input.
    `protected` | `Tokenizer(AttributeFactory factory)` Construct a tokenizer with no input, awaiting a call to `setReader(java.io.Reader)` to provide input.

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `close()` Releases resources associated with this stream.
    `protected int` | `correctOffset(int currentOff)` Return the corrected offset.
    `void` | `reset()` This method is called by a consumer before it begins consumption using `TokenStream.incrementToken()`.
    `void` | `setReader(Reader input)` Expert: Set a new reader on the Tokenizer.

    - ### Methods inherited from class org.apache.lucene.analysis.TokenStream

      `end, incrementToken`

    - ### Methods inherited from class org.apache.lucene.util.AttributeSource

      `addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, endAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, removeAllAttributes, restoreState, toString`

    - ### Methods inherited from class java.lang.Object

      `clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

- - ### Field Detail

    - #### input

          protected Reader input

      The text source for this Tokenizer.

  - ### Constructor Detail

    - #### Tokenizer

          protected Tokenizer()

      Construct a tokenizer with no input, awaiting a call to `setReader(java.io.Reader)` to provide input.

    - #### Tokenizer

          protected Tokenizer(AttributeFactory factory)

      Construct a tokenizer with no input, awaiting a call to `setReader(java.io.Reader)` to provide input.
      Parameters:
        `factory` - attribute factory.

  - ### Method Detail

    - #### close

          public void close()
                     throws IOException

      Releases resources associated with this stream.

      If you override this method, always call `super.close()`, otherwise some internal state will not be correctly reset (e.g., `Tokenizer` will throw `IllegalStateException` on reuse).

      NOTE: The default implementation closes the input Reader, so be sure to call `super.close()` when overriding this method.

      Specified by:
        `close` in interface `Closeable`
      Specified by:
        `close` in interface `AutoCloseable`
      Overrides:
        `close` in class `TokenStream`
      Throws:
        `IOException`

    - #### correctOffset

          protected final int correctOffset(int currentOff)

      Return the corrected offset. If `input` is a `CharFilter` subclass this method calls `CharFilter.correctOffset(int)`, else returns `currentOff`.
      Parameters:
        `currentOff` - offset as seen in the output
      Returns:
        corrected offset based on the input
      See Also:
        `CharFilter.correctOffset(int)`

    - #### setReader

          public final void setReader(Reader input)

      Expert: Set a new reader on the Tokenizer. Typically, an analyzer (in its tokenStream method) will use this to re-use a previously created tokenizer.

    - #### reset

          public void reset()
                     throws IOException

      Description copied from class: `TokenStream`
      This method is called by a consumer before it begins consumption using `TokenStream.incrementToken()`.

      Resets this stream to a clean state. Stateful implementations must implement this method so that they can be reused, just as if they had been created fresh.

      If you override this method, always call `super.reset()`, otherwise some internal state will not be correctly reset (e.g., `Tokenizer` will throw `IllegalStateException` on further usage).

      Overrides:
        `reset` in class `TokenStream`
      Throws:
        `IOException`

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