org.codehaus.jackson

## Class JsonNode

- java.lang.Object
- - org.codehaus.jackson.JsonNode

- All Implemented Interfaces:
    Iterable<JsonNode>
  Direct Known Subclasses:
    BaseJsonNode

      public abstract class JsonNode
      extends Object
      implements Iterable<JsonNode>

  Base class for all JSON nodes, which form the basis of JSON Tree Model that Jackson implements. One way to think of these nodes is to consider them similar to DOM nodes in XML DOM trees.

  As a general design rule, most accessors ("getters") are included in this base class, to allow for traversing structure without type casts. Most mutators, however, need to be accessed through specific sub-classes (such as `org.codehaus.jackson.node.ObjectNode` and `org.codehaus.jackson.node.ArrayNode`). This seems sensible because proper type information is generally available when building or modifying trees, but less often when reading a tree (newly built from parsed JSON content).

  Actual concrete sub-classes can be found from package `org.codehaus.jackson.node`, which is in 'mapper' jar (whereas this class is in 'core' jar, since it is declared as nominal type for operations in `ObjectCodec`)

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `protected static List<JsonNode>` | `NO_NODES`
    `protected static List<String>` | `NO_STRINGS`

  - ### Constructor Summary

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

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `boolean` | `asBoolean()` Method that will try to convert value of this node to a Java boolean.
    `boolean` | `asBoolean(boolean defaultValue)` Method that will try to convert value of this node to a Java boolean.
    `double` | `asDouble()` Method that will try to convert value of this node to a Java double.
    `double` | `asDouble(double defaultValue)` Method that will try to convert value of this node to a Java double.
    `int` | `asInt()` Method that will try to convert value of this node to a Java int.
    `int` | `asInt(int defaultValue)` Method that will try to convert value of this node to a Java int.
    `long` | `asLong()` Method that will try to convert value of this node to a Java long.
    `long` | `asLong(long defaultValue)` Method that will try to convert value of this node to a Java long.
    `abstract String` | `asText()` Method that will return valid String representation of the container value, if the node is a value node (method `isValueNode()` returns true), otherwise empty String.
    `abstract JsonToken` | `asToken()` Method that can be used for efficient type detection when using stream abstraction for traversing nodes.
    `abstract boolean` | `equals(Object o)` Equality for node objects is defined as full (deep) value equality.
    `abstract JsonNode` | `findParent(String fieldName)` Method for finding a JSON Object that contains specified field, within this node or its descendants.
    `List<JsonNode>` | `findParents(String fieldName)` Method for finding a JSON Object that contains specified field, within this node or its descendants.
    `abstract List<JsonNode>` | `findParents(String fieldName, List<JsonNode> foundSoFar)`
    `abstract JsonNode` | `findPath(String fieldName)` Method similar to `findValue(java.lang.String)`, but that will return a "missing node" instead of null if no field is found.
    `abstract JsonNode` | `findValue(String fieldName)` Method for finding a JSON Object field with specified name in this node or its child nodes, and returning value it has.
    `List<JsonNode>` | `findValues(String fieldName)` Method for finding JSON Object fields with specified name, and returning found ones as a List.
    `abstract List<JsonNode>` | `findValues(String fieldName, List<JsonNode> foundSoFar)`
    `List<String>` | `findValuesAsText(String fieldName)` Similar to `findValues(java.lang.String)`, but will additionally convert values into Strings, calling `getValueAsText()`.
    `abstract List<String>` | `findValuesAsText(String fieldName, List<String> foundSoFar)`
    `JsonNode` | `get(int index)` Method for accessing value of the specified element of an array node.
    `JsonNode` | `get(String fieldName)` Method for accessing value of the specified field of an object node.
    `BigInteger` | `getBigIntegerValue()`
    `byte[]` | `getBinaryValue()` Method to use for accessing binary content of binary nodes (nodes for which `isBinary()` returns true); or for Text Nodes (ones for which `getTextValue()` returns non-null value), to read decoded base64 data.
    `boolean` | `getBooleanValue()` Method to use for accessing JSON boolean values (value literals 'true' and 'false').
    `BigDecimal` | `getDecimalValue()`
    `double` | `getDoubleValue()`
    `Iterator<JsonNode>` | `getElements()` Method for accessing all value nodes of this Node, iff this node is a JSON Array or Object node.
    `Iterator<String>` | `getFieldNames()` Method for accessing names of all fields for this Node, iff this node is a JSON Object node.
    `Iterator<Map.Entry<String,JsonNode>>` | `getFields()`
    `int` | `getIntValue()` Returns integer value for this node, if and only if this node is numeric (`isNumber()` returns true).
    `long` | `getLongValue()`
    `abstract JsonParser.NumberType` | `getNumberType()` If this node is a numeric type (as per `isNumber()`), returns native type that node uses to store the numeric value.
    `Number` | `getNumberValue()` Returns numeric value for this node, if and only if this node is numeric (`isNumber()` returns true); otherwise returns null
    `JsonNode` | `getPath(int index)` Deprecated. Use `path(int)` instead
    `JsonNode` | `getPath(String fieldName)` Deprecated. Use `path(String)` instead
    `String` | `getTextValue()` Method to use for accessing String values.
    `boolean` | `getValueAsBoolean()` Deprecated. Since 1.9, use `asBoolean()` instead
    `boolean` | `getValueAsBoolean(boolean defaultValue)` Deprecated. Since 1.9, use `asBoolean()` instead
    `double` | `getValueAsDouble()` Deprecated. Since 1.9, use `asDouble()` instead
    `double` | `getValueAsDouble(double defaultValue)` Deprecated. Since 1.9, use `asDouble()` instead
    `int` | `getValueAsInt()` Deprecated. Since 1.9, use `asInt()` instead
    `int` | `getValueAsInt(int defaultValue)` Deprecated. Since 1.9, use `asInt()` instead
    `long` | `getValueAsLong()` Deprecated. Since 1.9, use `asLong()` instead
    `long` | `getValueAsLong(long defaultValue)` Deprecated. Since 1.9, use `asLong()` instead
    `String` | `getValueAsText()` Deprecated. Since 1.9, use `asText()` instead
    `boolean` | `has(int index)` Method that allows checking whether this node is JSON Array node and contains a value for specified index If this is the case (including case of specified indexing having null as value), returns true; otherwise returns false.
    `boolean` | `has(String fieldName)` Method that allows checking whether this node is JSON Object node and contains value for specified property.
    `boolean` | `isArray()`
    `boolean` | `isBigDecimal()`
    `boolean` | `isBigInteger()`
    `boolean` | `isBinary()` Method that can be used to check if this node represents binary data (Base64 encoded).
    `boolean` | `isBoolean()` Method that can be used to check if this node was created from Json boolean value (literals "true" and "false").
    `boolean` | `isContainerNode()` Method that returns true for container nodes: Arrays and Objects.
    `boolean` | `isDouble()`
    `boolean` | `isFloatingPointNumber()`
    `boolean` | `isInt()`
    `boolean` | `isIntegralNumber()`
    `boolean` | `isLong()`
    `boolean` | `isMissingNode()` Method that returns true for "virtual" nodes which represent missing entries constructed by path accessor methods when there is no actual node matching given criteria.
    `boolean` | `isNull()` Method that can be used to check if this node was created from Json liternal null value.
    `boolean` | `isNumber()`
    `boolean` | `isObject()`
    `boolean` | `isPojo()` Method that can be used to check if the node is a wrapper for a POJO ("Plain Old Java Object" aka "bean".
    `boolean` | `isTextual()`
    `boolean` | `isValueNode()` Method that returns true for all value nodes: ones that are not containers, and that do not represent "missing" nodes in the path.
    `Iterator<JsonNode>` | `iterator()` Same as calling `getElements()`; implemented so that convenience "for-each" loop can be used for looping over elements of JSON Array constructs.
    `abstract JsonNode` | `path(int index)` This method is similar to `get(int)`, except that instead of returning null if no such element exists (due to index being out of range, or this node not being an array), a "missing node" (node that returns true for `isMissingNode()`) will be returned.
    `abstract JsonNode` | `path(String fieldName)` This method is similar to `get(String)`, except that instead of returning null if no such value exists (due to this node not being an object, or object not having value for the specified field), a "missing node" (node that returns true for `isMissingNode()`) will be returned.
    `int` | `size()` Method that returns number of child nodes this node contains: for Array nodes, number of child elements, for Object nodes, number of fields, and for all other nodes 0.
    `abstract String` | `toString()` Note: marked as abstract to ensure all implementation classes define it properly.
    `abstract JsonParser` | `traverse()` Method for constructing a `JsonParser` instance for iterating over contents of the tree that this node is root of.
    `JsonNode` | `with(String propertyName)` Method that can be called on object nodes, to access a property that has object value; or if no such property exists, to create and return such object node.

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

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

- - ### Field Detail

    - #### NO_NODES

          protected static final List<JsonNode> NO_NODES

    - #### NO_STRINGS

          protected static final List<String> NO_STRINGS

  - ### Constructor Detail

    - #### JsonNode

          protected JsonNode()

  - ### Method Detail

    - #### isValueNode

          public boolean isValueNode()

      Method that returns true for all value nodes: ones that are not containers, and that do not represent "missing" nodes in the path. Such value nodes represent String, Number, Boolean and null values from JSON.

      Note: one and only one of methods `isValueNode()`, `isContainerNode()` and `isMissingNode()` ever returns true for any given node.

    - #### isContainerNode

          public boolean isContainerNode()

      Method that returns true for container nodes: Arrays and Objects.

      Note: one and only one of methods `isValueNode()`, `isContainerNode()` and `isMissingNode()` ever returns true for any given node.

    - #### isMissingNode

          public boolean isMissingNode()

      Method that returns true for "virtual" nodes which represent missing entries constructed by path accessor methods when there is no actual node matching given criteria.

      Note: one and only one of methods `isValueNode()`, `isContainerNode()` and `isMissingNode()` ever returns true for any given node.

    - #### isArray

          public boolean isArray()

      Returns:
        True if this node represents Json Array

    - #### isObject

          public boolean isObject()

      Returns:
        True if this node represents Json Object

    - #### isPojo

          public boolean isPojo()

      Method that can be used to check if the node is a wrapper for a POJO ("Plain Old Java Object" aka "bean". Returns true only for instances of `POJONode`.
      Returns:
        True if this node wraps a POJO

    - #### isNumber

          public boolean isNumber()

      Returns:
        True if this node represents a numeric Json value

    - #### isIntegralNumber

          public boolean isIntegralNumber()

      Returns:
        True if this node represents an integral (integer) numeric Json value

    - #### isFloatingPointNumber

          public boolean isFloatingPointNumber()

      Returns:
        True if this node represents a non-integral numeric Json value

    - #### isInt

          public boolean isInt()

      Returns:
        True if this node represents an integral numeric Json value that withs in Java int value space

    - #### isLong

          public boolean isLong()

      Returns:
        True if this node represents an integral numeric Json value that fits in Java long value space (but not int value space, i.e. `isInt()` returns false)

    - #### isDouble

          public boolean isDouble()

    - #### isBigDecimal

          public boolean isBigDecimal()

    - #### isBigInteger

          public boolean isBigInteger()

    - #### isTextual

          public boolean isTextual()

    - #### isBoolean

          public boolean isBoolean()

      Method that can be used to check if this node was created from Json boolean value (literals "true" and "false").

    - #### isNull

          public boolean isNull()

      Method that can be used to check if this node was created from Json liternal null value.

    - #### isBinary

          public boolean isBinary()

      Method that can be used to check if this node represents binary data (Base64 encoded). Although this will be externally written as Json String value, `isTextual()` will return false if this method returns true.
      Returns:
        True if this node represents base64 encoded binary data

    - #### asToken

          public abstract JsonToken asToken()

      Method that can be used for efficient type detection when using stream abstraction for traversing nodes. Will return the first `JsonToken` that equivalent stream event would produce (for most nodes there is just one token but for structured/container types multiple)
      Since:
        1.3

    - #### getNumberType

          public abstract JsonParser.NumberType getNumberType()

      If this node is a numeric type (as per `isNumber()`), returns native type that node uses to store the numeric value.

    - #### getTextValue

          public String getTextValue()

      Method to use for accessing String values. Does NOT do any conversions for non-String value nodes; for non-String values (ones for which `isTextual()` returns false) null will be returned. For String values, null is never returned (but empty Strings may be)
      Returns:
        Textual value this node contains, iff it is a textual json node (comes from Json String value entry)

    - #### getBinaryValue

          public byte[] getBinaryValue()
                                throws IOException

      Method to use for accessing binary content of binary nodes (nodes for which `isBinary()` returns true); or for Text Nodes (ones for which `getTextValue()` returns non-null value), to read decoded base64 data. For other types of nodes, returns null.
      Returns:
        Binary data this node contains, iff it is a binary node; null otherwise
      Throws:
        `IOException`

    - #### getBooleanValue

          public boolean getBooleanValue()

      Method to use for accessing JSON boolean values (value literals 'true' and 'false'). For other types, always returns false.
      Returns:
        Textual value this node contains, iff it is a textual json node (comes from Json String value entry)

    - #### getNumberValue

          public Number getNumberValue()

      Returns numeric value for this node, if and only if this node is numeric (`isNumber()` returns true); otherwise returns null
      Returns:
        Number value this node contains, if any (null for non-number nodes).

    - #### getIntValue

          public int getIntValue()

      Returns integer value for this node, if and only if this node is numeric (`isNumber()` returns true). For other types returns 0. For floating-point numbers, value is truncated using default Java coercion, similar to how cast from double to int operates.
      Returns:
        Integer value this node contains, if any; 0 for non-number nodes.

    - #### getLongValue

          public long getLongValue()

    - #### getDoubleValue

          public double getDoubleValue()

    - #### getDecimalValue

          public BigDecimal getDecimalValue()

    - #### getBigIntegerValue

          public BigInteger getBigIntegerValue()

    - #### get

          public JsonNode get(int index)

      Method for accessing value of the specified element of an array node. For other nodes, null is always returned.

      For array nodes, index specifies exact location within array and allows for efficient iteration over child elements (underlying storage is guaranteed to be efficiently indexable, i.e. has random-access to elements). If index is less than 0, or equal-or-greater than `node.size()`, null is returned; no exception is thrown for any index.

      Returns:
        Node that represent value of the specified element, if this node is an array and has specified element. Null otherwise.

    - #### get

          public JsonNode get(String fieldName)

      Method for accessing value of the specified field of an object node. If this node is not an object (or it does not have a value for specified field name), or if there is no field with such name, null is returned.
      Returns:
        Node that represent value of the specified field, if this node is an object and has value for the specified field. Null otherwise.

    - #### asText

          public abstract String asText()

      Method that will return valid String representation of the container value, if the node is a value node (method `isValueNode()` returns true), otherwise empty String.
      Since:
        1.9 (replaces `getValueAsText`)

    - #### asInt

          public int asInt()

      Method that will try to convert value of this node to a Java int. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an int (including structured types like Objects and Arrays), default value of 0 will be returned; no exceptions are thrown.

      Since:
        1.9 (replaces `getValueAsInt`)

    - #### asInt

          public int asInt(int defaultValue)

      Method that will try to convert value of this node to a Java int. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an int (including structured types like Objects and Arrays), specified defaultValue will be returned; no exceptions are thrown.

      Since:
        1.9 (replaces `getValueAsInt`)

    - #### asLong

          public long asLong()

      Method that will try to convert value of this node to a Java long. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an long (including structured types like Objects and Arrays), default value of 0 will be returned; no exceptions are thrown.

      Since:
        1.9 (replaces `getValueAsLong`)

    - #### asLong

          public long asLong(long defaultValue)

      Method that will try to convert value of this node to a Java long. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an long (including structured types like Objects and Arrays), specified defaultValue will be returned; no exceptions are thrown.

      Since:
        1.9 (replaces `getValueAsLong`)

    - #### asDouble

          public double asDouble()

      Method that will try to convert value of this node to a Java double. Numbers are coerced using default Java rules; booleans convert to 0.0 (false) and 1.0 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an int (including structured types like Objects and Arrays), default value of 0.0 will be returned; no exceptions are thrown.

      Since:
        1.9 (replaces `getValueAsDouble`)

    - #### asDouble

          public double asDouble(double defaultValue)

      Method that will try to convert value of this node to a Java double. Numbers are coerced using default Java rules; booleans convert to 0.0 (false) and 1.0 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an int (including structured types like Objects and Arrays), specified defaultValue will be returned; no exceptions are thrown.

      Since:
        1.9 (replaces `getValueAsLong`)

    - #### asBoolean

          public boolean asBoolean()

      Method that will try to convert value of this node to a Java boolean. JSON booleans map naturally; integer numbers other than 0 map to true, and 0 maps to false and Strings 'true' and 'false' map to corresponding values.

      If representation can not be converted to a boolean value (including structured types like Objects and Arrays), default value of false will be returned; no exceptions are thrown.

      Since:
        1.9 (replaces `getValueAsBoolean`)

    - #### asBoolean

          public boolean asBoolean(boolean defaultValue)

      Method that will try to convert value of this node to a Java boolean. JSON booleans map naturally; integer numbers other than 0 map to true, and 0 maps to false and Strings 'true' and 'false' map to corresponding values.

      If representation can not be converted to a boolean value (including structured types like Objects and Arrays), specified defaultValue will be returned; no exceptions are thrown.

      Since:
        1.9 (replaces `getValueAsBoolean`)

    - #### getValueAsText

          @Deprecated
          public String getValueAsText()

      Deprecated. Since 1.9, use `asText()` instead
      Method that will return valid String representation of the container value, if the node is a value node (method `isValueNode()` returns true), otherwise null.

      Note: to serialize nodes of any type, you should call `toString()` instead.

    - #### getValueAsInt

          @Deprecated
          public int getValueAsInt()

      Deprecated. Since 1.9, use `asInt()` instead
      Method that will try to convert value of this node to a Java int. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an int (including structured types like Objects and Arrays), default value of 0 will be returned; no exceptions are thrown.

      Since:
        1.6

    - #### getValueAsInt

          @Deprecated
          public int getValueAsInt(int defaultValue)

      Deprecated. Since 1.9, use `asInt()` instead
      Method that will try to convert value of this node to a Java int. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an int (including structured types like Objects and Arrays), specified defaultValue will be returned; no exceptions are thrown.

      Since:
        1.6

    - #### getValueAsLong

          @Deprecated
          public long getValueAsLong()

      Deprecated. Since 1.9, use `asLong()` instead
      Method that will try to convert value of this node to a Java long. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an long (including structured types like Objects and Arrays), default value of 0 will be returned; no exceptions are thrown.

      Since:
        1.6

    - #### getValueAsLong

          @Deprecated
          public long getValueAsLong(long defaultValue)

      Deprecated. Since 1.9, use `asLong()` instead
      Method that will try to convert value of this node to a Java long. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an long (including structured types like Objects and Arrays), specified defaultValue will be returned; no exceptions are thrown.

      Since:
        1.6

    - #### getValueAsDouble

          @Deprecated
          public double getValueAsDouble()

      Deprecated. Since 1.9, use `asDouble()` instead
      Method that will try to convert value of this node to a Java double. Numbers are coerced using default Java rules; booleans convert to 0.0 (false) and 1.0 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an int (including structured types like Objects and Arrays), default value of 0.0 will be returned; no exceptions are thrown.

      Since:
        1.6

    - #### getValueAsDouble

          @Deprecated
          public double getValueAsDouble(double defaultValue)

      Deprecated. Since 1.9, use `asDouble()` instead
      Method that will try to convert value of this node to a Java double. Numbers are coerced using default Java rules; booleans convert to 0.0 (false) and 1.0 (true), and Strings are parsed using default Java language integer parsing rules.

      If representation can not be converted to an int (including structured types like Objects and Arrays), specified defaultValue will be returned; no exceptions are thrown.

      Since:
        1.6

    - #### getValueAsBoolean

          @Deprecated
          public boolean getValueAsBoolean()

      Deprecated. Since 1.9, use `asBoolean()` instead
      Method that will try to convert value of this node to a Java boolean. JSON booleans map naturally; integer numbers other than 0 map to true, and 0 maps to false and Strings 'true' and 'false' map to corresponding values.

      If representation can not be converted to a boolean value (including structured types like Objects and Arrays), default value of false will be returned; no exceptions are thrown.

      Since:
        1.7

    - #### getValueAsBoolean

          @Deprecated
          public boolean getValueAsBoolean(boolean defaultValue)

      Deprecated. Since 1.9, use `asBoolean()` instead
      Method that will try to convert value of this node to a Java boolean. JSON booleans map naturally; integer numbers other than 0 map to true, and 0 maps to false and Strings 'true' and 'false' map to corresponding values.

      If representation can not be converted to a boolean value (including structured types like Objects and Arrays), specified defaultValue will be returned; no exceptions are thrown.

      Since:
        1.7

    - #### has

          public boolean has(String fieldName)

      Method that allows checking whether this node is JSON Object node and contains value for specified property. If this is the case (including properties with explicit null values), returns true; otherwise returns false.

      This method is equivalent to:

             node.get(fieldName) != null

      (since return value of get() is node, not value node contains)
      Parameters:
        `fieldName` - Name of element to check
      Returns:
        True if this node is a JSON Object node, and has a property entry with specified name (with any value, including null value)
      Since:
        1.6

    - #### has

          public boolean has(int index)

      Method that allows checking whether this node is JSON Array node and contains a value for specified index If this is the case (including case of specified indexing having null as value), returns true; otherwise returns false.

      Note: array element indexes are 0-based.

      This method is equivalent to:

             node.get(index) != null

      Parameters:
        `index` - Index to check
      Returns:
        True if this node is a JSON Object node, and has a property entry with specified name (with any value, including null value)
      Since:
        1.6

    - #### findValue

          public abstract JsonNode findValue(String fieldName)

      Method for finding a JSON Object field with specified name in this node or its child nodes, and returning value it has. If no matching field is found in this node or its descendants, returns null.
      Parameters:
        `fieldName` - Name of field to look for
      Returns:
        Value of first matching node found, if any; null if none
      Since:
        1.6

    - #### findValues

          public final List<JsonNode> findValues(String fieldName)

      Method for finding JSON Object fields with specified name, and returning found ones as a List. Note that sub-tree search ends if a field is found, so possible children of result nodes are not included. If no matching fields are found in this node or its descendants, returns an empty List.
      Parameters:
        `fieldName` - Name of field to look for
      Since:
        1.6

    - #### findValuesAsText

          public final List<String> findValuesAsText(String fieldName)

      Similar to `findValues(java.lang.String)`, but will additionally convert values into Strings, calling `getValueAsText()`.
      Since:
        1.6

    - #### findPath

          public abstract JsonNode findPath(String fieldName)

      Method similar to `findValue(java.lang.String)`, but that will return a "missing node" instead of null if no field is found. Missing node is a specific kind of node for which `isMissingNode()` returns true; and all value access methods return empty or missing value.
      Parameters:
        `fieldName` - Name of field to look for
      Returns:
        Value of first matching node found; or if not found, a "missing node" (non-null instance that has no value)
      Since:
        1.6

    - #### findParent

          public abstract JsonNode findParent(String fieldName)

      Method for finding a JSON Object that contains specified field, within this node or its descendants. If no matching field is found in this node or its descendants, returns null.
      Parameters:
        `fieldName` - Name of field to look for
      Returns:
        Value of first matching node found, if any; null if none
      Since:
        1.6

    - #### findParents

          public final List<JsonNode> findParents(String fieldName)

      Method for finding a JSON Object that contains specified field, within this node or its descendants. If no matching field is found in this node or its descendants, returns null.
      Parameters:
        `fieldName` - Name of field to look for
      Returns:
        Value of first matching node found, if any; null if none
      Since:
        1.6

    - #### findValues

          public abstract List<JsonNode> findValues(String fieldName,
                                  List<JsonNode> foundSoFar)

    - #### findValuesAsText

          public abstract List<String> findValuesAsText(String fieldName,
                                      List<String> foundSoFar)

    - #### findParents

          public abstract List<JsonNode> findParents(String fieldName,
                                   List<JsonNode> foundSoFar)

    - #### size

          public int size()

      Method that returns number of child nodes this node contains: for Array nodes, number of child elements, for Object nodes, number of fields, and for all other nodes 0.
      Returns:
        For non-container nodes returns 0; for arrays number of contained elements, and for objects number of fields.

    - #### iterator

          public final Iterator<JsonNode> iterator()

      Same as calling `getElements()`; implemented so that convenience "for-each" loop can be used for looping over elements of JSON Array constructs.
      Specified by:
        `iterator` in interface `Iterable<JsonNode>`

    - #### getElements

          public Iterator<JsonNode> getElements()

      Method for accessing all value nodes of this Node, iff this node is a JSON Array or Object node. In case of Object node, field names (keys) are not included, only values. For other types of nodes, returns empty iterator.

    - #### getFieldNames

          public Iterator<String> getFieldNames()

      Method for accessing names of all fields for this Node, iff this node is a JSON Object node.

    - #### getFields

          public Iterator<Map.Entry<String,JsonNode>> getFields()

      Returns:
        Iterator that can be used to traverse all key/value pairs for object nodes; empty iterator (no contents) for other types
      Since:
        1.8 (although existed in ObjectNode since 1.0 or so)

    - #### path

          public abstract JsonNode path(String fieldName)

      This method is similar to `get(String)`, except that instead of returning null if no such value exists (due to this node not being an object, or object not having value for the specified field), a "missing node" (node that returns true for `isMissingNode()`) will be returned. This allows for convenient and safe chained access via path calls.

    - #### getPath

          @Deprecated
          public final JsonNode getPath(String fieldName)

      Deprecated. Use `path(String)` instead
      Alias of `path(String)`.

    - #### path

          public abstract JsonNode path(int index)

      This method is similar to `get(int)`, except that instead of returning null if no such element exists (due to index being out of range, or this node not being an array), a "missing node" (node that returns true for `isMissingNode()`) will be returned. This allows for convenient and safe chained access via path calls.

    - #### getPath

          @Deprecated
          public final JsonNode getPath(int index)

      Deprecated. Use `path(int)` instead
      Alias of `path(int)`.

    - #### with

          public JsonNode with(String propertyName)

      Method that can be called on object nodes, to access a property that has object value; or if no such property exists, to create and return such object node. If node method is called on is not Object node, or if property exists and has value that is not object node, `UnsupportedOperationException` is thrown
      Since:
        1.8

    - #### traverse

          public abstract JsonParser traverse()

      Method for constructing a `JsonParser` instance for iterating over contents of the tree that this node is root of. Functionally equivalent to first serializing tree using `ObjectCodec` and then re-parsing but more efficient.

    - #### toString

          public abstract String toString()

      Note: marked as abstract to ensure all implementation classes define it properly.

      Overrides:
        `toString` in class `Object`

    - #### equals

          public abstract boolean equals(Object o)

      Equality for node objects is defined as full (deep) value equality. This means that it is possible to compare complete JSON trees for equality by comparing equality of root nodes.

      Note: marked as abstract to ensure all implementation classes define it properly and not rely on definition from `Object`.

      Overrides:
        `equals` in class `Object`