How can I work with the received DATA from Azure IoT Hub

问题

I receive the Data:

public void accept(PartitionReceiver receiver)
{
    System.out.println("** Created receiver on partition " + partitionId);
    try {
        while (true) {
            Iterable<EventData> receivedEvents = receiver.receive(10).get();
            int batchSize = 0;
            if (receivedEvents != null)
            {
                for(EventData receivedEvent: receivedEvents)
                {                                    
                    System.out.println(String.format("| Time: %s", receivedEvent.getSystemProperties().getEnqueuedTime()));
                    System.out.println(String.format("| Device ID: %s", receivedEvent.getProperties().get("iothub-connection-device-id")));
                    System.out.println(String.format("| Message Payload: %s", new String(receivedEvent.getBody(), Charset.defaultCharset())));
                    batchSize++;
                }
            }
        }
    } catch (Exception e)
    {
        System.out.println("Failed to receive messages: " + e.getMessage());
    }
}

Here i become the product name and price:

System.out.println(String.format("| Message Payload: %s", new String(receivedEvent.getBody(), Charset.defaultCharset())));

How can i take the Payload, product into a String product; and the price into double price;?

回答1:

As @Aravind said, you can define a POJO class to package the data as object properties like Payload, and serialize & deserialize the data as event body between a POJO and a json string using some json library, such as jackson, fastjson, or choose a favorite one from http://www.json.org/.

回答2:

Peter Pan and Aravind helped me to solve the Problem.

Here is the solution for the problem:

public class Product {
public Product(){

}
    private String product;
    private Double price;

public Product(String json ){
    Gson gson=new Gson();
    try{
        Product product =gson.fromJson(json, Product.class);
        if (product!=null){
            System.out.println("Name: " +product.getProduct());
        }
    }catch (Exception e){
        System.out.println("failed: " +e.getMessage());
    }
}

    public String getProduct() {
        return product;
    }

    public Double getPrice() {
        return price;
    }
 }

Here i read the JSON String in into a Object from the Class Product, the Product class contains variables, product und price with getter. It works!

    public Product(String json ){
    Gson gson=new Gson();
    try{
        Product product =gson.fromJson(json, Product.class);
        if (product!=null){
            System.out.println("Name: " +product.getProduct());
        }
    }catch (Exception e){
        System.out.println("failed: " +e.getMessage());
    }
}

来源：https://stackoverflow.com/questions/38028130/how-can-i-work-with-the-received-data-from-azure-iot-hub