Question

我正在尝试反序列化更新S3上的文件时向HTTPS端点发布的SNS消息。由于我找不到这样的SNS消息的任何标准包装类，我自己编写了包装器：

public class SnsNotificationMessage {
    private final String type;
    private final String messageId;
    private final String topicArn;
    private final String subject;
    private final S3EventNotification message;
    private final DateTime timestamp;
    private final String signatureVersion;
    private final String signature;
    private final String signingCertURL;
    private final String unsubscribeURL;

    @JsonCreator
    public SnsNotificationMessage(@JsonProperty("Type") String type, 
                                  @JsonProperty("MessageId")String messageId, 
                                  @JsonProperty("TopicArn") String topicArn, 
                                  @JsonProperty("Subject") String subject, 
                                  @JsonProperty("Message") S3EventNotification message, 
                                  @JsonProperty("Timestamp") DateTime timestamp, 
                                  @JsonProperty("SignatureVersion") String signatureVersion, 
                                  @JsonProperty("Signature") String signature, 
                                  @JsonProperty("SigningCertURL") String signingCertURL, 
                                  @JsonProperty("UnsubscribeURL") String unsubscribeURL) {
        this.type = type;
        this.messageId = messageId;
        this.topicArn = topicArn;
        this.subject = subject;
        this.message = message;
        this.timestamp = timestamp;
        this.signatureVersion = signatureVersion;
        this.signature = signature;
        this.signingCertURL = signingCertURL;
        this.unsubscribeURL = unsubscribeURL;
    }

    public String getType() {
        return type;
    }

    public String getMessageId() {
        return messageId;
    }

    public String getTopicArn() {
        return topicArn;
    }

    public String getSubject() {
        return subject;
    }

    public S3EventNotification getMessage() {
        return message;
    }

    public DateTime getTimestamp() {
        return timestamp;
    }
    public String getSignatureVersion() {
        return signatureVersion;
    }

    public String getSignature() {
        return signature;
    }

    public String getSigningCertURL() {
        return signingCertURL;
    }

    public String getUnsubscribeURL() {
        return unsubscribeURL;
    }   
}

无论如何，当我尝试反序列化它时，它似乎无法反序列化S3EventNotification对象：

Exception in thread "main" com.amazonaws.AmazonClientException: Unable to parse Json String.
Caused by: com.fasterxml.jackson.databind.JsonMappingException: Can not instantiate value of type [simple type, class com.amazonaws.services.s3.event.S3EventNotification] from String value ('{"Records":[{"eventVersion":"2.0","eventSource":"aws:s3","awsRegion":"eu-central-1","eventTime":"2016-06-24T16:38:46.692Z","eventName":"ObjectCreated:Put","userIdentity":{"principalId":"AWS:AIDAJYIVJE6VBFWIRPGI4"},"requestParameters":{"sourceIPAddress":"54.239.6.12"},"responseElements":{"x-amz-request-id":"4AF210318149235D","x-amz-id-2":"fyHT/8YQYwLehZhMK41NZVCVI9z5UiL9F3o2iBzI9Qea7P5v6GY/9qlaUZLaTnbFX6CLf7ts6Ss="},"s3":{"s3SchemaVersion":"1.0","configurationId":"ManualsUpdate","bucket":{"name":"mybucketname","ownerIdentity":{"principalId":"A3PMDPD5DZRTH7"},"arn":"arn:aws:s3:::mybucket"},"object":{"key":"manuals/velum/APP_B.pdf","size":819609,"eTag":"ebde6fb2ef4a041b40f0c88a36283ed9","sequencer":"00576D6206898586C7"}}}]}'); no single-String constructor/factory method
at [Source: {
  "Type" : "Notification",
  "MessageId" : "a377f3c7-e519-509a-9d23-bc20814f82d9",
  "TopicArn" : "arn:aws:sns:eu-central-1:133857750848:Manual_Updates",
  "Subject" : "Amazon S3 Notification",
  "Message" : "{\"Records\":[{\"eventVersion\":\"2.0\",\"eventSource\":\"aws:s3\",\"awsRegion\":\"eu-central-1\",\"eventTime\":\"2016-06-24T16:38:46.692Z\",\"eventName\":\"ObjectCreated:Put\",\"userIdentity\":{\"principalId\":\"AWS:AIDAJYIVJE6VBFWIRPGI4\"},\"requestParameters\":{\"sourceIPAddress\":\"54.239.6.12\"},\"responseElements\":{\"x-amz-request-id\":\"4AF210318149235D\",\"x-amz-id-2\":\"fyHT/8YQYwLehZhMK41NZVCVI9z5UiL9F3o2iBzI9Qea7P5v6GY/9qlaUZLaTnbFX6CLf7ts6Ss=\"},\"s3\":{\"s3SchemaVersion\":\"1.0\",\"configurationId\":\"ManualsUpdate\",\"bucket\":{\"name\":\"mybucket\",\"ownerIdentity\":{\"principalId\":\"A3PMDPD5DZRTH7\"},\"arn\":\"arn:aws:s3:::mybucket\"},\"object\":{\"key\":\"manuals/velum/APP_B.pdf\",\"size\":819609,\"eTag\":\"ebde6fb2ef4a041b40f0c88a36283ed9\",\"sequencer\":\"00576D6206898586C7\"}}}]}",
  "Timestamp" : "2016-06-24T16:38:46.802Z",
  "SignatureVersion" : "1",
  "Signature" : "WvEi+Y6DxDbXzqIjmbpJo1YHGDU+mgkRaMLlr6WQZkm53qpp8ch8cvWMtYq3LCYWiuQb6+95Gp+OfUFPulKCrxgis9KrHHJ8ozU8ZXI6Y8P693kNLYqEkro9DEjbaR63xw1Se+6KGpQm/kYJEn/AJCTr47sK3bmfsy4esuVWrw7F9PCUfJGzVfgB8S7z5N5DyPBROPAJ+1DyjPyYlv9AGM8Dw5LsdP4PjfOoEoKZZQ4iBJaKr5lFc7iDq+8SKGt0YwJWGAKYm08Lkx4oMBTojXBshK7cG6CUZbFCOXXG+F5cSffBENN1dK/1xrCvKDRdqc1+J4Y+JEDy/KCoPAcvEQ==",
  "SigningCertURL" : "https://sns.eu-central-1.amazonaws.com/SimpleNotificationService-bb750dd426d95ee9390147a5624348ee.pem",
  "UnsubscribeURL" : "https://sns.eu-central-1.amazonaws.com/?Action=Unsubscribe&SubscriptionArn=arn:aws:sns:eu-central-1:133857750848:Manual_Updates:9c1bb86d-836c-46d4-bd44-f7625f77f7bf"
}; line: 5, column: 39] (through reference chain: org.project.resources.notifications.models.SnsNotificationMessage["Message"])

奇怪的是，如果我尝试仅单独反序列化S3EventNotification字符串，它会正确地反序列化，所以看起来它是将S3EventNotification作为参数传递给构造函数的东西。我该怎么办？

Answer 1

好的，我找到了答案。问题是Message值是＆＃34; global＆＃34;中的一个String。字符串，而不是对象。

通过Jackson从S3文件更新反序列化SNS消息时出现JsonMappingException

1 个答案: