Type-Testing Methods

Each type-testing method resolves the node identified by this-node and sets an output flag to 1 if the node matches the described type, or 0. The methods return an INTEGER of 0 upon successful completion or nonzero if the node ID cannot be resolved.

The common syntax for the type-testing methods is:

These are the required arguments for the type-testing methods.

Required Argument: This-node

Property	Value
Direction	Input
Data Type	BIGINT
Description	Node ID to test. Passing a null or invalid node ID causes the method to return a nonzero error code.

Required Argument: is-flag

Property	Value
Direction	Output
Data Type	INTEGER
Description	Set to 1 if the type matches otherwise set to 0.

ISxxx Methods Used in Type-Testing Methods Syntax

Method	Sets is-flag to 1 when the node is:
ISOBJECT	a JSON object (`{…}`)
ISARRAY	a JSON array (`[…]`)
ISSTRING	a JSON string, including an empty string.
ISINT	a JSON integer (a number with no decimal point or exponent).
ISFLOAT	A JSON floating-point number that contains a . or exponent.
ISNUMBER	a numeric type, integer or floating-point number.
ISBOOLTRUE	the JSON literal, true.
ISBOOLFALSE	the JSON literal, false.
ISBOOL	true or false.
ISNULL	the JSON literal, null.

This example demonstrates the functionality of the type-testing methods.

dcl int rc rc1; dcl bigint nodeid;

rc = jst.findNode(rootid, '["scores"][0]', nodeid);

rc1 = jst.isNumber(nodeid, rc);

if rc = 1 then put 'First score is a number';

rc1 = jst.isInt(nodeid, rc);

if rc = 1 then put 'First score is an integer';

rc1 = jst.isFloat(nodeid, rc);

if rc = 1 then put 'First score is a float';