public String getSourceDBClusterParameterGroupIdentifier() {
        return this.sourceDBClusterParameterGroupIdentifier;
    }
<p>
The identifier or Amazon Resource Name (ARN) for the source DB cluster parameter group. For information about
creating an ARN, see <a
href="https://docs.aws.amazon.com/neptune/latest/UserGuide/tagging.ARN.html#tagging.ARN.Constructing">
Constructing an Amazon Resource Name (ARN)</a>.
</p>
<p>
Constraints:
</p>
<ul>
<li>
<p>
Must specify a valid DB cluster parameter group.
</p>
</li>
<li>
<p>
If the source DB cluster parameter group is in the same Amazon Region as the copy, specify a valid DB parameter
group identifier, for example <code>my-db-cluster-param-group</code>, or a valid ARN.
</p>
</li>
<li>
<p>
If the source DB parameter group is in a different Amazon Region than the copy, specify a valid DB cluster
parameter group ARN, for example <code>arn:aws:rds:us-east-1:123456789012:cluster-pg:custom-cluster-group1</code>
.
</p>
</li>
</ul>

@return The identifier or Amazon Resource Name (ARN) for the source DB cluster parameter group. For information
        about creating an ARN, see <a
        href="https://docs.aws.amazon.com/neptune/latest/UserGuide/tagging.ARN.html#tagging.ARN.Constructing">
        Constructing an Amazon Resource Name (ARN)</a>.</p>
        <p>
        Constraints:
        </p>
        <ul>
        <li>
        <p>
        Must specify a valid DB cluster parameter group.
        </p>
        </li>
        <li>
        <p>
        If the source DB cluster parameter group is in the same Amazon Region as the copy, specify a valid DB
        parameter group identifier, for example <code>my-db-cluster-param-group</code>, or a valid ARN.
        </p>
        </li>
        <li>
        <p>
        If the source DB parameter group is in a different Amazon Region than the copy, specify a valid DB
        cluster parameter group ARN, for example
        <code>arn:aws:rds:us-east-1:123456789012:cluster-pg:custom-cluster-group1</code>.
        </p>
        </li>
aws-java-sdk-neptune/src/main/java/com/amazonaws/services/neptune/model/CopyDBClusterParameterGroupRequest.java