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Twin Class

  • Reference
Package:
com.microsoft.azure.sdk.iot.device.twin
  • java.lang.Object
    • com.microsoft.azure.sdk.iot.device.twin.Twin

public class Twin

Representation of a single Twin.

The Twin can contain one TwinCollection of Tags, and one TwinCollection of properties.desired.

Each entity in the collections can contain a associated TwinMetadata.

These metadata are provided by the Service and contains information about the last updated date time, and version.

For instance, the following is a valid Twin, represented as initialTwin  

</code> in the rest API. <pre><code>{

    "initialTwin": {

        "tags":{

            "SpeedUnity":"MPH",

            "$metadata":{

                "$lastUpdated":"2017-09-21T02:07:44.238Z",

                "$lastUpdatedVersion":4,

                "SpeedUnity":{

                    "$lastUpdated":"2017-09-21T02:07:44.238Z",

                    "$lastUpdatedVersion":4

                }

            },

            "$version":4

        },

        "properties":{

            "desired": {

                "MaxSpeed":{

                    "Value":500,

                    "NewValue":300

                },

                "$metadata":{

                    "$lastUpdated":"2017-09-21T02:07:44.238Z",

                    "$lastUpdatedVersion":4,

                    "MaxSpeed":{

                        "$lastUpdated":"2017-09-21T02:07:44.238Z",

                        "$lastUpdatedVersion":4,

                        "Value":{

                            "$lastUpdated":"2017-09-21T02:07:44.238Z",

                            "$lastUpdatedVersion":4

                        },

                        "NewValue":{

                            "$lastUpdated":"2017-09-21T02:07:44.238Z",

                            "$lastUpdatedVersion":4

                        }

                    }

                },

                "$version":4

            },

            "reported": {

                "MaxSpeed":{

                    "Value":500,

                    "NewValue":300

                },

                "$metadata":{

                    "$lastUpdated":"2017-09-21T02:07:44.238Z",

                    "$lastUpdatedVersion":5,

                    "MaxSpeed":{

                        "$lastUpdated":"2017-09-21T02:07:44.238Z",

                        "$lastUpdatedVersion":4,

                        "Value":{

                            "$lastUpdated":"2017-09-21T02:07:44.238Z",

                            "$lastUpdatedVersion":5

                        },

                        "NewValue":{

                            "$lastUpdated":"2017-09-21T02:07:44.238Z",

                            "$lastUpdatedVersion":4

                        }

                    }

                },

                "$version":6

            }

        }

    }

}

</code></pre></p>

Constructor Summary

Constructor Description
Twin(TwinCollection desiredProperty, TwinCollection reportedProperty)

CONSTRUCTOR

This constructor creates an instance of the Twin with the provided TwinCollection tags and desired properties.

When serialized, this class will looks like the following example: 

"initialTwin": {
        "tags":{
            "SpeedUnity":"MPH",
            "$version":4
        }
        "properties":{
            "desired":{
                "MaxSpeed":{
                    "Value":500,
                    "NewValue":300
                },
                "$version":4
            }
        }
    }
     
    }

Method Summary

Modifier and Type Method and Description
Twin createFromDesiredPropertyJson(String json)

Factory

Create a new instance of the Twin parsing the provided string as a JSON with only desired properties information.
Twin createFromPropertiesJson(String json)

Factory

Create a new instance of the Twin parsing the provided string as a JSON with only desired properties information.
Twin createFromReportedPropertyJson(String json)

Factory

Create a new instance of the Twin parsing the provided string as a JSON with only reported properties information.
Twin createFromTwinJson(String json)

Factory

Create a new instance of the Twin parsing the provided string as a JSON with the full Twin information.
TwinCollection getDesiredProperties()

Getter for the desired property.
TwinCollection getReportedProperties()

Getter for the reported property.
JsonElement toJsonElement()

Serializer

Creates aJsonElement  

</code> , which the content represents the information in this class and its subclasses in a JSON format.</p>

This is useful if the caller will integrate this JSON with JSON from other classes to generate a consolidated JSON.

String toString()

Creates a pretty print JSON with the content of this class and subclasses.

Constructor Details

Twin

public Twin(TwinCollection desiredProperty, TwinCollection reportedProperty)

CONSTRUCTOR

This constructor creates an instance of the Twin with the provided TwinCollection tags and desired properties.

When serialized, this class will looks like the following example: 

"initialTwin": {
        "tags":{
            "SpeedUnity":"MPH",
            "$version":4
        }
        "properties":{
            "desired":{
                "MaxSpeed":{
                    "Value":500,
                    "NewValue":300
                },
                "$version":4
            }
        }
    }
     
    }

Parameters:

desiredProperty -

the TwinCollection with the desired properties. It can benull  

</code> . </p>
reportedProperty -

the TwinCollection with the reported properties. It can benull  

</code> . </p>

Method Details

createFromDesiredPropertyJson

public static Twin createFromDesiredPropertyJson(String json)

Factory

Create a new instance of the Twin parsing the provided string as a JSON with only desired properties information.

Parameters:

json -

theString  

</code> with the JSON received from the service. It cannot be<code>null 

</code> or empty. </p>

Returns:

The new instance of theTwin  

</code> . </p>

createFromPropertiesJson

public static Twin createFromPropertiesJson(String json)

Factory

Create a new instance of the Twin parsing the provided string as a JSON with only desired properties information.

Parameters:

json -

theString  

</code> with the JSON received from the service. It cannot be<code>null 

</code> or empty. </p>

Returns:

The new instance of theTwin  

</code> . </p>

createFromReportedPropertyJson

public static Twin createFromReportedPropertyJson(String json)

Factory

Create a new instance of the Twin parsing the provided string as a JSON with only reported properties information.

Parameters:

json -

theString  

</code> with the JSON received from the service. It cannot be<code>null 

</code> or empty. </p>

Returns:

The new instance of theTwin  

</code> . </p>

createFromTwinJson

public static Twin createFromTwinJson(String json)

Factory

Create a new instance of the Twin parsing the provided string as a JSON with the full Twin information.

Parameters:

json -

theString  

</code> with the JSON received from the service. It cannot be<code>null 

</code> or empty. </p>

Returns:

The new instance of theTwin  

</code> . </p>

getDesiredProperties

public TwinCollection getDesiredProperties()

Getter for the desired property.

Returns:

TheTwinCollection  

</code> with the desired property content. It can be<code>null 

</code> . </p>

getReportedProperties

public TwinCollection getReportedProperties()

Getter for the reported property.

Returns:

TheTwinCollection  

</code> with the reported property content. It can be<code>null 

</code> . </p>

toJsonElement

public JsonElement toJsonElement()

Serializer

Creates aJsonElement  

</code> , which the content represents the information in this class and its subclasses in a JSON format.</p>

This is useful if the caller will integrate this JSON with JSON from other classes to generate a consolidated JSON.

Returns:

TheJsonElement  

</code> with the content of this class. </p>

toString

public String toString()

Creates a pretty print JSON with the content of this class and subclasses.

Returns:

TheString  

</code> with the pretty print JSON. </p>

Applies to