public void setPrincipal(String principal) {
        this.principal = principal;
    }
<p>
Specifies the ID of the principal whose resource shares you want to retrieve. This can be an Amazon Web Services
account ID, an organization ID, an organizational unit ID, or the <a
href="https://docs.aws.amazon.com/general/latest/gr/aws-arns-and-namespaces.html">Amazon Resource Name (ARN)</a>
of an individual IAM role or user.
</p>
<p>
You cannot specify this parameter if the association type is <code>RESOURCE</code>.
</p>

@param principal
       Specifies the ID of the principal whose resource shares you want to retrieve. This can be an Amazon Web
       Services account ID, an organization ID, an organizational unit ID, or the <a
       href="https://docs.aws.amazon.com/general/latest/gr/aws-arns-and-namespaces.html">Amazon Resource Name
       (ARN)</a> of an individual IAM role or user.</p>
       <p>
       You cannot specify this parameter if the association type is <code>RESOURCE</code>.
aws-java-sdk-ram/src/main/java/com/amazonaws/services/ram/model/GetResourceShareAssociationsRequest.java