public java.util.List<String> getDbGroups() {
        if (dbGroups == null) {
            dbGroups = new com.amazonaws.internal.SdkInternalList<String>();
        }
        return dbGroups;
    }
<p>
A list of the names of existing database groups that the user named in <code>DbUser</code> will join for the
current session, in addition to any group memberships for an existing user. If not specified, a new user is added
only to PUBLIC.
</p>
<p>
Database group name constraints
</p>
<ul>
<li>
<p>
Must be 1 to 64 alphanumeric characters or hyphens
</p>
</li>
<li>
<p>
Must contain only lowercase letters, numbers, underscore, plus sign, period (dot), at symbol (@), or hyphen.
</p>
</li>
<li>
<p>
First character must be a letter.
</p>
</li>
<li>
<p>
Must not contain a colon ( : ) or slash ( / ).
</p>
</li>
<li>
<p>
Cannot be a reserved word. A list of reserved words can be found in <a
href="http://docs.aws.amazon.com/redshift/latest/dg/r_pg_keywords.html">Reserved Words</a> in the Amazon Redshift
Database Developer Guide.
</p>
</li>
</ul>

@return A list of the names of existing database groups that the user named in <code>DbUser</code> will join for
        the current session, in addition to any group memberships for an existing user. If not specified, a new
        user is added only to PUBLIC.</p>
        <p>
        Database group name constraints
        </p>
        <ul>
        <li>
        <p>
        Must be 1 to 64 alphanumeric characters or hyphens
        </p>
        </li>
        <li>
        <p>
        Must contain only lowercase letters, numbers, underscore, plus sign, period (dot), at symbol (@), or
        hyphen.
        </p>
        </li>
        <li>
        <p>
        First character must be a letter.
        </p>
        </li>
        <li>
        <p>
        Must not contain a colon ( : ) or slash ( / ).
        </p>
        </li>
        <li>
        <p>
        Cannot be a reserved word. A list of reserved words can be found in <a
        href="http://docs.aws.amazon.com/redshift/latest/dg/r_pg_keywords.html">Reserved Words</a> in the Amazon
        Redshift Database Developer Guide.
        </p>
        </li>
aws-java-sdk-redshift/src/main/java/com/amazonaws/services/redshift/model/GetClusterCredentialsRequest.java