public Termination withCallingRegions(String... callingRegions) {
        if (this.callingRegions == null) {
            setCallingRegions(new java.util.ArrayList<String>(callingRegions.length));
        }
        for (String ele : callingRegions) {
            this.callingRegions.add(ele);
        }
        return this;
    }
<p>
The countries to which calls are allowed, in ISO 3166-1 alpha-2 format. Required.
</p>
<p>
<b>NOTE:</b> This method appends the values to the existing list (if any). Use
{@link #setCallingRegions(java.util.Collection)} or {@link #withCallingRegions(java.util.Collection)} if you want
to override the existing values.
</p>

@param callingRegions
       The countries to which calls are allowed, in ISO 3166-1 alpha-2 format. Required.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-chimesdkvoice/src/main/java/com/amazonaws/services/chimesdkvoice/model/Termination.java