public void setHandler(String handler) {
        this.handler = handler;
    }
<p>
The name of the method within your code that Lambda calls to run your function. Handler is required if the
deployment package is a .zip file archive. The format includes the file name. It can also include namespaces and
other qualifiers, depending on the runtime. For more information, see <a
href="https://docs.aws.amazon.com/lambda/latest/dg/foundation-progmodel.html">Lambda programming model</a>.
</p>

@param handler
       The name of the method within your code that Lambda calls to run your function. Handler is required if the
       deployment package is a .zip file archive. The format includes the file name. It can also include
       namespaces and other qualifiers, depending on the runtime. For more information, see <a
       href="https://docs.aws.amazon.com/lambda/latest/dg/foundation-progmodel.html">Lambda programming
       model</a>.
aws-java-sdk-lambda/src/main/java/com/amazonaws/services/lambda/model/CreateFunctionRequest.java