Use IoT Platform SDK for Java - IoT Platform - Alibaba Cloud Documentation Center

IoT Platform SDK for Java allows you to efficiently manage IoT Platform resources by using Java programs. You can add the SDK as a dependency to your Maven project. You can also download the installation package to an on-premises directory and install the SDK.

Install OSS SDK for Android

Install a Java integrated development environment (IDE).
Download a Java installation package from the official Java website and follow the instructions as prompted to install Java.

Install IoT Platform SDK for Java.

Download a Maven installation package from the official Apache Maven website.

Add the following dependencies to your Maven project:

The dependency for IoT Platform SDK for Java of the latest version:

<!-- https://mvnrepository.com/artifact/com.aliyun/aliyun-java-sdk-iot -->
<dependency>
    <groupId>com.aliyun</groupId>
    <artifactId>aliyun-java-sdk-iot</artifactId>
    <version>7.41.0</version>
</dependency>

The dependency for Alibaba Cloud SDK for Java:

<dependency>
    <groupId>com.aliyun</groupId>
    <artifactId>aliyun-java-sdk-core</artifactId>
    <version>4.5.6</version>
</dependency>

Initialize IoT Platform SDK for Java

Create the profile object from IClientProfile to store SDK initialization information. Then, create the client instance from DefaultAcsClient. Use the DefaultAcsClient(profile) method to load the SDK initialization information.

String accessKey = "${accessKey}";
String accessSecret = "${accessSecret}";
IClientProfile profile = DefaultProfile.getProfile("${RegionId}", accessKey, accessSecret);
DefaultAcsClient client = new DefaultAcsClient(profile); // Initializes an SDK client.

Parameter	Description
accessKey	The AccessKey ID of your Alibaba Cloud account. You can go to the Alibaba Cloud Management Console to create or view your AccessKey ID.
accessSecret	The AccessKey secret of your Alibaba Cloud account.
profile	The object that is used to store the SDK initialization information. `${RegionId}` specifies the ID of the region where IoT Platform is activated. You can view the region in the upper-left corner of the IoT Platform console. For more information about the formats of region IDs, see Regions and zones.

The following example shows how to initialize the SDK when IoT Platform is activated in the China (Shanghai) region:

String accessKey = "${accessKey}";
String accessSecret = "${accessSecret}";
IClientProfile profile = DefaultProfile.getProfile("cn-shanghai", accessKey, accessSecret);
DefaultAcsClient client = new DefaultAcsClient(profile);

Initiate a request

The SDK encapsulates two classes for each API operation. The class names are in the ${API operation name}+"Request" and ${API operation name}+"Response" formats.

${API operation name}+"Request": This class is used to call an API operation. You can use the request instance of this class and call the set +${request parameters} method to configure the request parameters.
${API operation name}+"Response": You can call the getAcsResponse(request) method of the client instance that is created from DefaultAcsClient to obtain a response. You can use the response instance of the ${API operation name}+"Response" class and call the get +${response parameters} method to obtain the values of the response parameters.
For example, you can call the response.getSuccess() method to obtain the Success parameter. This parameter is a common response parameter that indicates whether a call is successful. Common response parameters also include the RequestId, ErrorMessage, and Code parameters.

For more information about the API operations of IoT Platform, see List of operations by function. For more information about the request and response parameters of each API operation, see the API documentation.

The following example shows how to call the Pub operation to publish a message to a topic. For more information about request parameters, see Pub.

Important

In the following sample code, ${iotInstanceId} specifies the ID of an instance. You can view the ID of the instance on the Overview page in the IoT Platform console.

If your instance has an ID, you must specify the ID for this parameter. Otherwise, the call fails.
If no Overview page or ID is generated for your instance, you do not need to configure this parameter. You must delete the request code that is related to the IotInstanceId parameter or specify an empty string ("") for the parameter. Otherwise, the call fails.

For more information about IoT Platform instances, see Overview. For information about how to purchase an instance, see Purchase Enterprise Edition instances. For more information, see FAQ about IoT Platform instances.

PubRequest request = new PubRequest(); 
request.setIotInstanceId("${iotInstanceId}"); 
request.setProductKey("${productKey}"); 
request.setMessageContent(Base64.encodeBase64String("hello world".getBytes())); 
request.setTopicFullName("/${productKey}/${deviceName}/user/get"); 
request.setQos(0); // QoS0 and QoS1 are supported.  
try 
{ 
   PubResponse response = client.getAcsResponse(request); 
   System.out.println(response.getSuccess()); 
   System.out.println(response.getCode());
   System.out.println(response.getErrorMessage());
} 
catch (ServerException e) 
{
   e.printStackTrace();
}
catch (ClientException e)
{
   System.out.println("ErrCode:" + e.getErrCode());
   System.out.println("ErrMsg:" + e.getErrMsg());
   e.printStackTrace();
}

Appendix: Sample code

You can view or download the sample code of API operations in IoT Platform SDK Sample Center. Sample code of SDKs for Java, Python, PHP, .NET, and Go is provided.

Alibaba Cloud OpenAPI Explorer provides online debugging tools for API operations. On the API Debugging page, you can search for API operations, call API operations, and generate sample code for API operations of different SDKs. On the right side of the page, you can view the sample code of an SDK on the Sample Code tab. On the Debugging Result tab, you can view the actual request URL and response in the JSON format.