XML and JSON variable support

WSO2 Business Process Server 3.6.0 onwards supports XML and JSON variables which can be read,created or updated within a BPMN process as follows:

For more information on creating a BPMN process, see Creating a BPMN Process.

Access From	Read/Query	Create/Update
Java Service Task	Yes	Yes
Condition Expressions	Yes	No
Script Task	Yes	Yes
BPMN REST API	Yes	Yes

JSON

JSON Node Object

In WSO2 BPS, JSON variables are represented by JsonNodeObject objects. The org.wso2.carbon.bpmn.core.types.datatypes.json.api.JsonNodeObject wraps the com.fasterxml.jackson.databind.JsonNode object and provides functions to query and update data in JSON format.

Function Description

Object jsonPath(String jsonPathStr)

This function evaluates jsonPath over JsonNodeObject and returns the evaluation result.

The returned object can be one of the following:

If the result is a JSON object, it will return a com.fasterxml.jackson.databind.JsonNode.
If the result is a JSON array, it will return a com.fasterxml.jackson.databind.node.ArrayNode.
Main primitive data types (String, Integer, Byte, Character, Short, Long, Float, Double, Boolean)

Note: This function returns a new object representing the evaluation results and not a reference to a node.

Sample Return

var fname = jsonJSVar.jsonPath("$.firstName");
var exec = jsonJSVar.jsonPath("$.execInfo");

JsonNode unwrap() This function unwraps and returns the wrapped JsonNode.

A set of useful and frequently used functions that are available in JsonNode, are exposed from the JsonNodeObject to make it easier to use JSON variables. However, if other functionality that is available is required, those functions can be unwrapped and used using the org.wso2.carbon.bpmn.core.types.datatypes.json.api.JsonNodeObject.unwrap() function. These functions are:

JsonNode findValue(String fieldName)

JsonNode findPath(String fieldName)

JsonNode findParent(String fieldName)

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

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

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

JsonNode path(String fieldName)

JsonNode path(int index)

String toString()

boolean equals(Object obj)

JsonNode get(int index)

JsonNode get(String fieldName)

boolean has(String fieldName)

boolean has(int index)

int size()

Iterator<JsonNode> elements()

Iterator<String> fieldNames()

Iterator<Map.Entry<String, JsonNode>> fields()

XML

With XML support, users can create variables with the XML data type and extract or set XML content with the help of the simple JAVA API provided in WSO2 BPS.

XML Document

XML variables are represented by the XMLDocument object org.wso2.carbon.bpmn.core.types.datatypes.xml.api.XMLDocument which implements org.w3x.dom.Document. It also provides a set of user friendly function to query and update XML content with XPath. The following functions are available for the XML variable type with WSO2 BPS.

`Object xPath(String xpathStr)`
Description	This function evaluates the XPath query and returns the relevant element.
xpathStr	The XPath expression that is to be evaluated.
Return	A `org.w3c.dom.NodeList` is returned if there is more than one elements in the result. A `org.w3c.dom.Node` object is returned if there is only one element in the result.

`Object xPath(String xpathStr, String returnType)`
Description	This function evaluates the XPath query and returns the specified return type.
xpathStr	The XPath expression that is to be evaluated.
returnType	The desired return type of the XPath evaluation. The supported return types are: `NODESET` `NODE` `STRING` `NUMBER` `BOOLEAN`
Return	The result of the XPath evaluation in the form of the specified return type.

`Node set(String xPathStr, Object obj)`
Description	This function sets, replaces or updates an object (string/element) to match the XPath provided. If a new element is added, this API will clone it and merge the new node to the target location that the XPath points to and will return the new cloned node.
xpathStr	The XPath to the target location where the object is to be set.
obj	The string or node object to be set.
Return	The node gets updated if the object is string and returns a newly added node if the object is an element.

`Node appendChild(String xPathToParent, Element element)`
Description	This function appends a child element to the target element.
xpathToParent	The XPath to the parent node.
element	The element that is to be appended.
Return	The node either gets appended or returns a newly added node if the object is an element.

`Node insertBefore(String xPathToTargetNode, Element element)`
Description	This function inserts a new child node before the specified existing node.
xpathToTargetNode	The XPath to the target node.
element	The element that is to be inserted.
Return	The node gets inserted.

`String toString()`
Description	This function will serialize the XML object to a string.

`Element createNewElement(String elementStr)`
Description	This function creates a new element. This is a util method.

Business Process Server 3.6.0

XML and JSON variable support

JSON

XML

`Object xPath(String xpathStr)`

`Object xPath(String xpathStr, String returnType)`

`Node set(String xPathStr, Object obj)`

`Node appendChild(String xPathToParent, Element element)`

`Node insertBefore(String xPathToTargetNode, Element element)`

`String toString()`

`Element createNewElement(String elementStr)`