public Proxy withPhoneNumberCountries(String... phoneNumberCountries) {
        if (this.phoneNumberCountries == null) {
            setPhoneNumberCountries(new java.util.ArrayList<String>(phoneNumberCountries.length));
        }
        for (String ele : phoneNumberCountries) {
            this.phoneNumberCountries.add(ele);
        }
        return this;
    }
<p>
The countries for proxy phone numbers to be selected from.
</p>
<p>
<b>NOTE:</b> This method appends the values to the existing list (if any). Use
{@link #setPhoneNumberCountries(java.util.Collection)} or {@link #withPhoneNumberCountries(java.util.Collection)}
if you want to override the existing values.
</p>

@param phoneNumberCountries
       The countries for proxy phone numbers to be selected from.
@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/Proxy.java