Maven - Unable to resolve dependency conflict b/w google-vision beta & aws-sdk sub-components

Question

I'm trying to use google-vision to fetch text from an image (uploaded to AWS S3) and store it in AWS Dynamo DB. I'm encountering dependency conflicts on jackson-core as both google-api and aws-java-sdk are using two different versions.

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Dependency Hierarchy

google-api-client: 1.22.0 uses jackson-core: 2.1.3

google-cloud-vision: 0.22.0-beta uses jackson-core: 2.1.3

aws-java-sdk: 1.11.106 uses jackson-core: 2.6.6

I tried "exclusions" and added explicit dependency in pom.xml to use jackson-core: 2.6.6. Google-vision api works fine with that change. However, AmazonDynamoDBClientBuilder fails with below error:

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Exception in thread "main" java.lang.IllegalAccessError: tried to access method com.amazonaws.AmazonWebServiceClient.<init>(Lcom/amazonaws/client/AwsSyncClientParams;)V from class com.amazonaws.services.dynamodbv2.AmazonDynamoDBClientBuilder
    at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClientBuilder.build(AmazonDynamoDBClientBuilder.java:60)
    at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClientBuilder.build(AmazonDynamoDBClientBuilder.java:26)
    at com.amazonaws.client.builder.AwsSyncClientBuilder.build(AwsSyncClientBuilder.java:46)
    at com.oneglint.ImageProcessing.AddItem.main(AddItem.java:133)

Following error is displayed when there was version conflict

Exception in thread "main" java.lang.NoSuchMethodError: com.fasterxml.jackson.core.JsonFactory.requiresPropertyOrdering()Z
    at com.fasterxml.jackson.databind.ObjectMapper.<init>(ObjectMapper.java:537)
    at com.fasterxml.jackson.databind.ObjectMapper.<init>(ObjectMapper.java:448)
    at com.amazonaws.partitions.PartitionsLoader.<clinit>(PartitionsLoader.java:51)
    at com.amazonaws.regions.RegionMetadataFactory.create(RegionMetadataFactory.java:30)
    at com.amazonaws.regions.RegionUtils.initialize(RegionUtils.java:64)
    at com.amazonaws.regions.RegionUtils.getRegionMetadata(RegionUtils.java:52)
    at com.amazonaws.regions.RegionUtils.getRegion(RegionUtils.java:105)
    at com.amazonaws.client.builder.AwsClientBuilder.withRegion(AwsClientBuilder.java:239)
    at com.oneglint.ImageProcessing.AddItem.main(AddItem.java:132)

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What am I missing here? Thanks for the help..

BTW, I'm using example code from github to achieve this. Here are the links:

DynamoDB example: https://github.com/awsdocs/aws-doc-sdk-examples/tree/master/java/example_code/dynamodb

Google Vision DetectText example: https://github.com/GoogleCloudPlatform/java-docs-samples/blob/master/vision/cloud-client/src/main/java/com/example/vision/Detect.java

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Additional Details

Both the examples are working fine if executed as independent projects. The problem occurs ONLY when both PutItem (AWS) & Detect (google-vision) classes are brought together in a single project, with appropriate code changes.

Answer 1

You can only have one version of jackson-core in your project. The easiest way to fix a version is to use <dependencyManagement> to set a version.

Your main problem is that jackson-core: 2.6.6 is not compatible with AmazonDynamoDBClientBuilder. The usual strategy is to try all versions from 2.1.3 to 2.6.6 until one of them works. If not, you can try to find versions of your amazon and google jars that require the same Jackson-core-version. In any case, this stupid and boring try-and-error.

If you do not come to any working solution, you can try to shade classes with maven-shade-plugin (I have not tried this, probably difficult) or you need to change your project in a way that not both dependencies are required.

Answer 2

After a lot of trial and error approach, the issue is finally solved.

It appears that I added multiple versions of aws-java-sdk jars during the process and an opennlp jar was associated with the project for some other module.

I had removed conflicting versions of aws-java-sdk and unnecessary libraries. Also, removed the exclusions and retained only the dependency addition in <dependencymanagement> for jackson-core.

Dependencies in my final pom listed below:

  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>com.amazonaws</groupId>
        <artifactId>aws-java-sdk-bom</artifactId>
        <version>1.11.106</version>
        <type>pom</type>
        <scope>import</scope>
      </dependency>
      <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>2.6.6</version>
      </dependency>
    </dependencies>
  </dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>com.google.apis</groupId>
      <artifactId>google-api-services-vision</artifactId>
      <version>v1-rev358-1.22.0</version>
    </dependency>
    <dependency>
      <groupId>com.google.api-client</groupId>
      <artifactId>google-api-client</artifactId>
      <version>1.22.0</version>
      <exclusions>
        <exclusion> <!-- exclude an old version of Guava -->
          <groupId>com.google.guava</groupId>
          <artifactId>guava-jdk5</artifactId>
        </exclusion>
      </exclusions>
    </dependency>
    <dependency>
      <groupId>com.google.guava</groupId>
      <artifactId>guava</artifactId>
      <version>20.0</version>
    </dependency>
    <dependency>
        <groupId>com.google.cloud</groupId>
        <artifactId>google-cloud-vision</artifactId>
        <version>0.22.0-beta</version>
    </dependency>
    <dependency>
        <groupId>com.amazonaws</groupId>
        <artifactId>aws-java-sdk-dynamodb</artifactId>
    </dependency>
  </dependencies>

Hope this helps others..