code: public ContainerExecResponseInner launchExec(String resourceGroupName, String containerGroupName, String containerName, ContainerExecRequest containerExecRequest) {
          return launchExecWithServiceResponseAsync(resourceGroupName, containerGroupName, containerName, containerExecRequest).toBlocking().single().body();
      }
docs: Starts the exec command for a specific container instance.
  Starts the exec command for a specified container instance in a specified resource group and container group.
  
  @param resourceGroupName The name of the resource group.
  @param containerGroupName The name of the container group.
  @param containerName The name of the container instance.
  @param containerExecRequest The request for the exec command.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @throws CloudException thrown if the request is rejected by server
  @throws RuntimeException all other wrapped checked exceptions if the request fails to be sent
  @return the ContainerExecResponseInner object if successful.