Step 2: Java Properties
In the ThingWorx environment, a Property represents a data point, which has a:
- Name
- Value
- Timestamp
- Quality (optional)
Define Properties
You can define attributes, base types and other aspects of ThingWorx properties.
Attributes
The table below provides information on the different attributes that are used to define a property.
| Attribute |
Details |
| name |
Specifies the name of the property that will appear in ThingWorx when users browse to bind the related Thing. |
| description |
Provides additional information for the property. |
| baseType |
Specifies the type of the property. For a list of base types supported by the SDK, refer to the BaseTypes chart below. |
BaseTypes
The table below provides information on the different types of properties that can be created in ThingWorx.
| BaseType |
Primitive |
Description |
| BOOLEAN |
BooleanPrimitive |
True or false values only |
| DATETIME |
DatetimePrimitive |
Date and time value |
| GROUPNAME |
StringPrimitive |
ThingWorx group name |
| HTML |
StringPrimitive |
HTML value |
| HYPERLINK |
StringPrimitve |
Hyperlink value |
| IMAGE |
ImagePrimitive |
Image value |
| IMAGELINK |
StringPrimitive |
Image link value |
| INFOTABLE |
InfoTablePrimitive |
ThingWorx infotable |
| INTEGER |
IntegerPrimitive |
32–bit integer value |
| JSON |
JSONPrimitive |
JSON structure |
| LOCATION |
LocationPrimitive |
ThingWorx location structure |
| MASHUPNAME |
StringPrimitive |
ThingWorx Mashup name |
| MENUNAME |
StringPrimitive |
ThingWorx menu name |
| NOTHING |
N/A |
No type (used for services to define void result) |
| NUMBER |
NumberPrimitive |
Double precision value |
| STRING |
StringPrimitive |
String value |
| QUERY |
N/A |
ThingWorx query structure |
| TEXT |
StringPrimitive |
Text value |
| THINGNAME |
StringPrimitive |
ThingWorx Thing name |
| USERNAME |
StringPrimitive |
ThingWorx user name |
| XML |
XMLPrimitive |
XML structure |
Aspects
Aspects define the ways to interact with a property. The table below provides information on frequently used Aspect attributes of a property.
| Attribute |
Description |
| isPersistent |
Set to TRUE for the ThingWorx server to persist the value even if it restarts. It is extremely expensive to have persistent values, so it is recommended to set this value to FALSE unless absolutely necessary. |
| isReadOnly |
Set to TRUE to inform the ThingWorx server that this value is only readable and cannot be changed by a request from the server. |
| dataChangeType |
Describes how the ThingWorx server responds when the value changes in the client application. Subscriptions to these value changes can be modeled in ThingWorx Core. If nothing needs to react to the property change, set this value to NEVER. |
| dataChangeThreshold |
Defines how much the value must change to trigger a change event. For example 0 (zero) indicates that any change triggers an event. A value of 10 (ten) for example would not trigger an update unless the value changed by an amount greater than or equal to 10. |
| defaultValue |
The default value is the value that ThingWorx Core uses when the RemoteThing connected to the device first starts up and has not received an update from the device. The value is different based on the different value for each base type. |
| cacheTime |
The amount of time that ThingWorx Core caches the value before reading it again. A value of -1 informs the server that the client application always sends its value and the server should never go and get it. A value of 0 (zero) indicates that every time the server uses the value, it should go and get it from the client application. Any other positive value indicates that the server caches the value for that many seconds and then retrieves it from the client application only after that time expired. |
| pushType |
Informs ThingWorx Core how the client application pushes its values to the server. |
NOTE: cacheTime and dataChangeThreshold are for subscribed (bound) properties ONLY.
DataChangeType Values
This field acts as the default value for the data change type field of the property when it is added to the remote Thing. The possible dataChangeType values are below:
| Value |
Description |
| ALWAYS |
Always notify of the value change even if the new value is the same as the last reported value. |
| VALUE |
Only notify of a change when a newly reported value is different than its previous value. |
| ON |
For BOOLEAN types, notify only when the value is true. |
| OFF |
For BOOLEAN types only, notify when the value is false. |
| NEVER |
Ignore all changes to this value. |
PushType Values
This aspect works in conjunction with cacheTime. The possible pushType values are below:
| Value |
Description |
| ALWAYS |
Send updates even if the value has not changed. It is common to use a cacheTime setting of -1 in this case. |
| VALUE |
Send updates only when the value changes. It is common to use a cacheTime setting of -1 in this case. |
| NEVER |
Never send the value, which indicates that ThingWorx server only writes to this value.It is common to use a cacheTime setting of 0 or greater in this case. |
| DEADBAND |
Added to support KEPServer, this push type is an absolute deadband (no percentages). It provides a cumulative threshold, such that the Edge device should send an update if its current data point exceeds Threshold compared to the last value sent to ThingWorx Core. It follows existing threshold fields limits. |
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