Add support for S3Object getObjectMetadata transform

[davidh44]

Motivation and Context

#6469 && #6571

Fixes migration tool bug where error is thrown if code contains S3Object.getObjectMetadata() chained to another method, e.g. object.getObjectMetadata().getCacheControl()

[ERROR] The recipe produced an error. Please report this to the recipe author.
[ERROR] Failed to execute goal org.openrewrite.maven:rewrite-maven-plugin:6.19.0:dryRun (default-cli) on project s3proxy: Execution default-cli of goal org.openrewrite.maven:rewrite-maven-plugin:6.19.0:dryRun failed: Error while visiting src/test/java/org/gaul/s3proxy/AwsSdkAnonymousTest.java: java.lang.ClassCastException: class org.openrewrite.java.tree.J$MethodInvocation cannot be cast to class org.openrewrite.java.tree.J$Identifier (org.openrewrite.java.tree.J$MethodInvocation and org.openrewrite.java.tree.J$Identifier are in unnamed module of loader org.codehaus.plexus.classworlds.realm.ClassRealm @15e08615)
[ERROR]   software.amazon.awssdk.v2migration.S3PutObjectRequestToV2$Visitor.saveMetadataValueAndRemoveStatement(S3PutObjectRequestToV2.java:417)

The root cause is S3TransformUtils.hasArguments() not working properly and always returning true. This occurs since OpenRewrite's J.MethodInvocation.getArguments() returns a List<Expression> with a J.Empty object when a method has no arguments. So method.getArguments().isEmpty() always returns false. Becuase of this, the recipe attempts to transform the getter (instead of just setters). When this getter is chained to another method, an error is thrown when the recipe attempts to cast J.MethodInvocation.getSelect() (another method) to J.Identifier - https://github.com/aws/aws-sdk-java-v2/blob/master/v2-migration/src/main/java/software/amazon/awssdk/v2migration/S3PutObjectRequestToV2.java#L417

The recipe also needs to remove the getObjectMetadata() method. In v1, getObject() returns S3Object. Whereas in v2, getObject() returns ResponseInputStream<GetObjectResponse>. There is no S3Object or ObjectMetadata POJO in v2, the metadata fields are set directly on GetObjectResponse / HeadObjectResponse.

The S3StreamingResponseToV2 recipe already adds the response() method - https://github.com/aws/aws-sdk-java-v2/blob/master/v2-migration/src/main/java/software/amazon/awssdk/v2migration/S3StreamingResponseToV2.java#L110

Modifications

• Update S3TransformUtils.hasArguments() to properly check for args in method, by looking for any Expression NOT of type J.Empty
• Add logic to S3PutObjectRequestToV2 recipe to remove the getObjectMetadata() method
• Separate minor fix: add imports for Tagging and GetObjectTaggingResponse in S3PojoToV2 recipe, to account for when they are instantiated standalone, not assigned to a variable, e.g., passed as arg

Testing

• Added getObjectMetadata() chained to another getter method, to the S3Streaming end-to-end test
• Tested migration tool successfully on customer project S3Proxy , and Gradle sample code

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• [] New feature (non-breaking change which adds functionality)

[sonarqubecloud]

Quality Gate failed

Failed conditions
0.0% Coverage on New Code (required ≥ 80%)

See analysis details on SonarQube Cloud

[github-actions]

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