public void setApiKeySource(String apiKeySource) {
        this.apiKeySource = apiKeySource;
    }
<p>
The source of the API key for metering requests according to a usage plan. Valid values are: &gt;
<code>HEADER</code> to read the API key from the <code>X-API-Key</code> header of a request.
<code>AUTHORIZER</code> to read the API key from the <code>UsageIdentifierKey</code> from a custom authorizer.
</p>

@param apiKeySource
       The source of the API key for metering requests according to a usage plan. Valid values are: &gt;
       <code>HEADER</code> to read the API key from the <code>X-API-Key</code> header of a request.
       <code>AUTHORIZER</code> to read the API key from the <code>UsageIdentifierKey</code> from a custom
       authorizer.
@see ApiKeySourceType
aws-java-sdk-api-gateway/src/main/java/com/amazonaws/services/apigateway/model/CreateRestApiResult.java