private Operation initOperation(HandlerMethod handlerMethod, Class<?> domainType, RequestMethod requestMethod) {
		Operation operation = new Operation();
		StringBuilder operationIdBuilder = new StringBuilder();
		operationIdBuilder.append(handlerMethod.getMethod().getName());
		if (domainType != null) {
			operationIdBuilder.append(STRING_SEPARATOR).append(domainType.getSimpleName().toLowerCase())
					.append(STRING_SEPARATOR).append(requestMethod.toString().toLowerCase());
		}
		operation.setOperationId(operationIdBuilder.toString());
		return operation;
	}
Init operation.

@param handlerMethod the handler method
@param domainType    the domain type
@param requestMethod the request method
@return the operation
springdoc-openapi-starter-common/src/main/java/org/springdoc/core/data/DataRestOperationService.java