TokenFilter
Date: 2016-12-03

com.fasterxml.jackson.core.filter

## Class TokenFilter

- java.lang.Object
- - com.fasterxml.jackson.core.filter.TokenFilter

- Direct Known Subclasses:
    JsonPointerBasedFilter

      public class TokenFilter
      extends java.lang.Object

  Strategy class that can be implemented to specify actual inclusion/exclusion criteria for filtering, used by `FilteringGeneratorDelegate`.
  Since:
    2.6

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `static TokenFilter` | `INCLUDE_ALL` Marker value that should be used to indicate inclusion of a structured value (sub-tree representing Object or Array), or value of a named property (regardless of type).

  - ### Constructor Summary

    Constructors
    Modifier | Constructor and Description
    --- | ---
    `protected` | `TokenFilter()`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `protected boolean` | `_includeScalar()` Overridable default implementation delegated to all scalar value inclusion check methods.
    `void` | `filterFinishArray()` Method called to indicate that output of non-filtered Array (one that may have been included either completely, or in part) is completed, in cases where filter other that `INCLUDE_ALL` was returned.
    `void` | `filterFinishObject()` Method called to indicate that output of non-filtered Object (one that may have been included either completely, or in part) is completed, in cases where filter other that `INCLUDE_ALL` was returned.
    `TokenFilter` | `filterStartArray()` Method called to check whether Array value at current output location should be included in output.
    `TokenFilter` | `filterStartObject()` Method called to check whether Object value at current output location should be included in output.
    `boolean` | `includeBinary()` Call made to verify whether leaf-level Binary value should be included in output or not.
    `boolean` | `includeBoolean(boolean value)` Call made to verify whether leaf-level boolean value should be included in output or not.
    `TokenFilter` | `includeElement(int index)` Method called to check whether array element with specified index (zero-based), at current output location, should be included in output.
    `boolean` | `includeEmbeddedValue(java.lang.Object ob)` Call made to verify whether leaf-level embedded (Opaque) value should be included in output or not.
    `boolean` | `includeNull()` Call made to verify whether leaf-level null value should be included in output or not.
    `boolean` | `includeNumber(java.math.BigDecimal v)` Call made to verify whether leaf-level `BigDecimal` value should be included in output or not.
    `boolean` | `includeNumber(java.math.BigInteger v)` Call made to verify whether leaf-level `BigInteger` value should be included in output or not.
    `boolean` | `includeNumber(double v)` Call made to verify whether leaf-level `double` value should be included in output or not.
    `boolean` | `includeNumber(float v)` Call made to verify whether leaf-level `float` value should be included in output or not.
    `boolean` | `includeNumber(int v)` Call made to verify whether leaf-level `int` value should be included in output or not.
    `boolean` | `includeNumber(long v)` Call made to verify whether leaf-level `long` value should be included in output or not.
    `TokenFilter` | `includeProperty(java.lang.String name)` Method called to check whether property value with specified name, at current output location, should be included in output.
    `boolean` | `includeRawValue()` Call made to verify whether leaf-level raw (pre-encoded, not quoted by generator) value should be included in output or not.
    `TokenFilter` | `includeRootValue(int index)` Method called to check whether root-level value, at current output location, should be included in output.
    `boolean` | `includeString(java.lang.String value)` Call made to verify whether leaf-level String value should be included in output or not.
    `boolean` | `includeValue(JsonParser p)` Call made when verifying whether a scaler value is being read from a parser.
    `java.lang.String` | `toString()`

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

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

- - ### Field Detail

    - #### INCLUDE_ALL

          public static final TokenFilter INCLUDE_ALL

      Marker value that should be used to indicate inclusion of a structured value (sub-tree representing Object or Array), or value of a named property (regardless of type). Note that if this instance is returned, it will used as a marker, and no actual callbacks need to be made. For this reason, it is more efficient to return this instance if the whole sub-tree is to be included, instead of implementing similar filter functionality explicitly.

  - ### Constructor Detail

    - #### TokenFilter

          protected TokenFilter()

  - ### Method Detail

    - #### filterStartObject

          public TokenFilter filterStartObject()

      Method called to check whether Object value at current output location should be included in output. Three kinds of return values may be used as follows:
      - `null` to indicate that the Object should be skipped
      - `INCLUDE_ALL` to indicate that the Object should be included completely in output
      - Any other `TokenFilter` implementation (possibly this one) to mean that further inclusion calls on return filter object need to be made on contained properties, as necessary. `filterFinishObject()` will also be called on returned filter object

      Default implementation returns `this`, which means that checks are made recursively for properties of the Object to determine possible inclusion.

      Returns:
        TokenFilter to use for further calls within Array, unless return value is `null` or `INCLUDE_ALL` (which have simpler semantics)

    - #### filterStartArray

          public TokenFilter filterStartArray()

      Method called to check whether Array value at current output location should be included in output. Three kinds of return values may be used as follows:
      - `null` to indicate that the Array should be skipped
      - `INCLUDE_ALL` to indicate that the Array should be included completely in output
      - Any other `TokenFilter` implementation (possibly this one) to mean that further inclusion calls on return filter object need to be made on contained element values, as necessary. `filterFinishArray()` will also be called on returned filter object

      Default implementation returns `this`, which means that checks are made recursively for elements of the array to determine possible inclusion.

      Returns:
        TokenFilter to use for further calls within Array, unless return value is `null` or `INCLUDE_ALL` (which have simpler semantics)

    - #### filterFinishObject

          public void filterFinishObject()

      Method called to indicate that output of non-filtered Object (one that may have been included either completely, or in part) is completed, in cases where filter other that `INCLUDE_ALL` was returned. This occurs when `JsonGenerator.writeEndObject()` is called.

    - #### filterFinishArray

          public void filterFinishArray()

      Method called to indicate that output of non-filtered Array (one that may have been included either completely, or in part) is completed, in cases where filter other that `INCLUDE_ALL` was returned. This occurs when `JsonGenerator.writeEndArray()` is called.

    - #### includeProperty

          public TokenFilter includeProperty(java.lang.String name)

      Method called to check whether property value with specified name, at current output location, should be included in output. Three kinds of return values may be used as follows:
      - `null` to indicate that the property and its value should be skipped
      - `INCLUDE_ALL` to indicate that the property and its value should be included completely in output
      - Any other `TokenFilter` implementation (possibly this one) to mean that further inclusion calls on returned filter object need to be made as necessary, to determine inclusion.

      The default implementation simply returns `this` to continue calling methods on this filter object, without full inclusion or exclusion.

      Returns:
        TokenFilter to use for further calls within property value, unless return value is `null` or `INCLUDE_ALL` (which have simpler semantics)

    - #### includeElement

          public TokenFilter includeElement(int index)

      Method called to check whether array element with specified index (zero-based), at current output location, should be included in output. Three kinds of return values may be used as follows:
      - `null` to indicate that the Array element should be skipped
      - `INCLUDE_ALL` to indicate that the Array element should be included completely in output
      - Any other `TokenFilter` implementation (possibly this one) to mean that further inclusion calls on returned filter object need to be made as necessary, to determine inclusion.

      The default implementation simply returns `this` to continue calling methods on this filter object, without full inclusion or exclusion.

      Returns:
        TokenFilter to use for further calls within element value, unless return value is `null` or `INCLUDE_ALL` (which have simpler semantics)

    - #### includeRootValue

          public TokenFilter includeRootValue(int index)

      Method called to check whether root-level value, at current output location, should be included in output. Three kinds of return values may be used as follows:
      - `null` to indicate that the root value should be skipped
      - `INCLUDE_ALL` to indicate that the root value should be included completely in output
      - Any other `TokenFilter` implementation (possibly this one) to mean that further inclusion calls on returned filter object need to be made as necessary, to determine inclusion.

      The default implementation simply returns `this` to continue calling methods on this filter object, without full inclusion or exclusion.

      Returns:
        TokenFilter to use for further calls within root value, unless return value is `null` or `INCLUDE_ALL` (which have simpler semantics)

    - #### includeValue

          public boolean includeValue(JsonParser p)
                               throws java.io.IOException

      Call made when verifying whether a scaler value is being read from a parser.

      Default action is to call `_includeScalar()` and return whatever it indicates.

      Throws:
        `java.io.IOException`

    - #### includeBoolean

          public boolean includeBoolean(boolean value)

      Call made to verify whether leaf-level boolean value should be included in output or not.

    - #### includeNull

          public boolean includeNull()

      Call made to verify whether leaf-level null value should be included in output or not.

    - #### includeString

          public boolean includeString(java.lang.String value)

      Call made to verify whether leaf-level String value should be included in output or not.

    - #### includeNumber

          public boolean includeNumber(int v)

      Call made to verify whether leaf-level `int` value should be included in output or not. NOTE: also called for `short`, `byte`

    - #### includeNumber

          public boolean includeNumber(long v)

      Call made to verify whether leaf-level `long` value should be included in output or not.

    - #### includeNumber

          public boolean includeNumber(float v)

      Call made to verify whether leaf-level `float` value should be included in output or not.

    - #### includeNumber

          public boolean includeNumber(double v)

      Call made to verify whether leaf-level `double` value should be included in output or not.

    - #### includeNumber

          public boolean includeNumber(java.math.BigDecimal v)

      Call made to verify whether leaf-level `BigDecimal` value should be included in output or not.

    - #### includeNumber

          public boolean includeNumber(java.math.BigInteger v)

      Call made to verify whether leaf-level `BigInteger` value should be included in output or not.

    - #### includeBinary

          public boolean includeBinary()

      Call made to verify whether leaf-level Binary value should be included in output or not.

      NOTE: no binary payload passed; assumption is this won't be of much use.

    - #### includeRawValue

          public boolean includeRawValue()

      Call made to verify whether leaf-level raw (pre-encoded, not quoted by generator) value should be included in output or not.

      NOTE: value itself not passed since it may come on multiple forms and is unlikely to be of much use in determining inclusion criteria.

    - #### includeEmbeddedValue

          public boolean includeEmbeddedValue(java.lang.Object ob)

      Call made to verify whether leaf-level embedded (Opaque) value should be included in output or not.

    - #### toString

          public java.lang.String toString()

      Overrides:
        `toString` in class `java.lang.Object`

    - #### _includeScalar

          protected boolean _includeScalar()

      Overridable default implementation delegated to all scalar value inclusion check methods. The default implementation simply includes all leaf values.