java - 使用 GSON 解析整个 AWS SQS 记录

Question

我现在一直尝试解析此消息，但没有成功。使用 AWS Simple Queue Service API，我按照说明执行以下操作...

for(Message m : Messages){
    System.out.println(m.getBody());
}

这将返回以下结构中的 JSON 字符串:

{
    "Records": [
        {
            "EventSource": "",
            "EventVersion": "",
            "EventSubscriptionArn": "",
            "Sns": {
                "Type": "",
                "MessageId": "",
                "TopicArn": "",
                "Subject": null,
                "Message": ""                
                "Timestamp": "",
                "SignatureVersion": "",
                "Signature": "”
                "SigningCertUrl": "",
                "UnsubscribeUrl": "",
                "MessageAttributes": {}
            }
        }
    ]
}

我一直在尝试使用 GSON 将整个事情解析为 Java 对象，以便我可以提取“Message”参数(也包含 JSON)，然后使用 GSON 解析它(当我传递该参数时完成并工作)直接发短信)。

这些是我设置的类，但这行不通——每个类都有公共(public) getter 和 setter......

记录类别:

public class Records {

    public ArrayList<ExceptionMessages> exceptionMessages = new ArrayList<ExceptionMessages>();

    public ArrayList<ExceptionMessages> getExceptionMessages() {
        return exceptionMessages;
    }

    public void setExceptionMessages(ArrayList<ExceptionMessages> exceptionMessages) {
        this.exceptionMessages = exceptionMessages;
    }

消息类别:

public class ExceptionMessages {

    public String EventSource;
    public String EventVersion;
    public String EventSubscriptionArn;
    public Sns messageJSON;     
}

Sns 类(存储消息的位置):

public class Sns {

    public String Type;
    public String MessageId;
    public String TopicArn;
    public String Subject;
    public String Message;
    public String Timestamp;
    public String SignatureVersion;
    public String Signature;
    public String SigningCertUrl;
    public String UnsubscribeUrl;
    public String MessageAttributes;
}

尝试 ArrayList 的 .get(0) 时出现空指针异常，因此它是空的并且未进行解析。

这就是我的称呼...

我将 m.getBody() 发送到解析方法并尝试像这样解析:

Gson gson = new Gson();
Records record = new Records();
gson.fromJson(JSONString.replaceAll("\\s+", ""), Records.class);

Answer 1

结构应该是

class RecordContainer {
    ArrayList<Record> Records;
}

class Record {
    public String EventSource;
    public String EventVersion;
    public String EventSubscriptionArn;
    public Sns Sns;     
}

class Sns {
    public String Type;
    public String MessageId;
    public String TopicArn;
    public String Subject;
    public String Message;
    public String Timestamp;
    public String SignatureVersion;
    public String Signature;
    public String SigningCertUrl;
    public String UnsubscribeUrl;
    public MessageAttributes MessageAttributes;
}