com.fasterxml.jackson.databind.node

Class ValueNode

java.lang.Object

com.fasterxml.jackson.databind.JsonNode

com.fasterxml.jackson.databind.node.BaseJsonNode

com.fasterxml.jackson.databind.node.ValueNode

All Implemented Interfaces:

TreeNode, JsonSerializable, Iterable<JsonNode>

Direct Known Subclasses:

BinaryNode, BooleanNode, MissingNode, NullNode, NumericNode, POJONode, TextNode

public abstract class ValueNode
extends BaseJsonNode

This intermediate base class is used for all leaf nodes, that is, all non-container (array or object) nodes, except for the "missing node".

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ValueNode()

Method Summary

Methods

Modifier and Type	Method and Description
abstract JsonToken	asToken() Method that can be used for efficient type detection when using stream abstraction for traversing nodes.
<T extends JsonNode> T	deepCopy() All current value nodes are immutable, so we can just return them as is.
ObjectNode	findParent(String fieldName) Method for finding a JSON Object that contains specified field, within this node or its descendants.
List<JsonNode>	findParents(String fieldName, List<JsonNode> foundSoFar)
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, List<JsonNode> foundSoFar)
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.
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	hasNonNull(int index) Method that is similar to JsonNode.has(int), but that will return false for explicitly added nulls.
boolean	hasNonNull(String fieldName) Method that is similar to JsonNode.has(String), but that will return false for explicitly added nulls.
JsonNode	path(int index) This method is similar to JsonNode.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 JsonNode.isMissingNode()) will be returned.
JsonNode	path(String fieldName) This method is similar to JsonNode.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 JsonNode.isMissingNode()) will be returned.
void	serializeWithType(JsonGenerator jg, SerializerProvider provider, TypeSerializer typeSer) Type information is needed, even if JsonNode instances are "plain" JSON, since they may be mixed with other types.
String	toString() Note: marked as abstract to ensure all implementation classes define it properly.

Methods inherited from class com.fasterxml.jackson.databind.node.BaseJsonNode

findPath, numberType, serialize, traverse, traverse

Methods inherited from class com.fasterxml.jackson.databind.JsonNode

asBoolean, asBoolean, asDouble, asDouble, asInt, asInt, asLong, asLong, asText, bigIntegerValue, binaryValue, booleanValue, canConvertToInt, canConvertToLong, decimalValue, doubleValue, elements, equals, fieldNames, fields, findParents, findValues, findValuesAsText, floatValue, getNodeType, intValue, isArray, isBigDecimal, isBigInteger, isBinary, isBoolean, isContainerNode, isDouble, isFloat, isFloatingPointNumber, isInt, isIntegralNumber, isLong, isMissingNode, isNull, isNumber, isObject, isPojo, isShort, isTextual, isValueNode, iterator, longValue, numberValue, shortValue, size, textValue, with, withArray

Methods inherited from class java.lang.Object

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

Constructor Detail

ValueNode

protected ValueNode()

Method Detail

deepCopy

public <T extends JsonNode> T deepCopy()

All current value nodes are immutable, so we can just return them as is.

Specified by:

deepCopy in class JsonNode

Returns:

Node that is either a copy of this node (and all non-leaf children); or, for immutable leaf nodes, node itself.

asToken

public abstract JsonToken asToken()

Description copied from class: BaseJsonNode

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)

Specified by:

asToken in interface TreeNode

Specified by:

asToken in class BaseJsonNode

serializeWithType

public void serializeWithType(JsonGenerator jg,
                     SerializerProvider provider,
                     TypeSerializer typeSer)
                       throws IOException,
                              JsonProcessingException

Description copied from class: BaseJsonNode

Type information is needed, even if JsonNode instances are "plain" JSON, since they may be mixed with other types.

Specified by:

serializeWithType in interface JsonSerializable

Specified by:

serializeWithType in class BaseJsonNode

Throws:

IOException

JsonProcessingException

toString

public String toString()

Description copied from class: JsonNode

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

Specified by:

toString in class JsonNode

get

public final JsonNode get(int index)

Description copied from class: JsonNode

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.

NOTE: if the element value has been explicitly set as null (which is different from removal!), a NullNode will be returned, not null.

Specified by:

get in interface TreeNode

Specified by:

get in class JsonNode

Returns:

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

path

public final JsonNode path(int index)

Description copied from class: JsonNode

This method is similar to JsonNode.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 JsonNode.isMissingNode()) will be returned. This allows for convenient and safe chained access via path calls.

Specified by:

path in interface TreeNode

Specified by:

path in class JsonNode

has

public final boolean has(int index)

Description copied from class: JsonNode

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

NOTE: this method will return true for explicitly added null values.

Overrides:

has in class JsonNode

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)

hasNonNull

public final boolean hasNonNull(int index)

Description copied from class: JsonNode

Method that is similar to JsonNode.has(int), but that will return false for explicitly added nulls.

This method is equivalent to:

   node.get(index) != null && !node.get(index).isNull()

Overrides:

hasNonNull in class JsonNode

get

public final JsonNode get(String fieldName)

Description copied from class: JsonNode

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.

NOTE: if the property value has been explicitly set as null (which is different from removal!), a NullNode will be returned, not null.

Specified by:

get in interface TreeNode

Overrides:

get in class JsonNode

Returns:

Node that represent value of the specified field, if this node is an object and has value for the specified field. Null otherwise.

path

public final JsonNode path(String fieldName)

Description copied from class: JsonNode

This method is similar to JsonNode.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 JsonNode.isMissingNode()) will be returned. This allows for convenient and safe chained access via path calls.

Specified by:

path in interface TreeNode

Specified by:

path in class JsonNode

has

public final boolean has(String fieldName)

Description copied from class: JsonNode

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)

NOTE: when explicit null values are added, this method will return true for such properties.

Overrides:

has in class JsonNode

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)

hasNonNull

public final boolean hasNonNull(String fieldName)

Description copied from class: JsonNode

Method that is similar to JsonNode.has(String), but that will return false for explicitly added nulls.

This method is functionally equivalent to:

   node.get(fieldName) != null && !node.get(fieldName).isNull()

Overrides:

hasNonNull in class JsonNode

findValue

public final JsonNode findValue(String fieldName)

Description copied from class: JsonNode

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.

Specified by:

findValue in class JsonNode

Parameters:

fieldName - Name of field to look for

Returns:

Value of first matching node found, if any; null if none

findParent

public final ObjectNode findParent(String fieldName)

Description copied from class: JsonNode

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.

Specified by:

findParent in class JsonNode

Parameters:

fieldName - Name of field to look for

Returns:

Value of first matching node found, if any; null if none

findValues

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

Specified by:

findValues in class JsonNode

findValuesAsText

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

Specified by:

findValuesAsText in class JsonNode

findParents

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

Specified by:

findParents in class JsonNode