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How to do function composition in Spring Cloud Stream when using classes

I'm working on a proof of concept for a Spring Cloud Stream application. I want to define my processing logic using classes that implement `Function`, `Consumer`, or `Supplier`.

I understand that Spring Cloud Stream allows for [function composition](https://cloud.spring.io/spring-cloud-function/reference/html/spring-cloud-function.html#_function_composition) using function beans, and declaring them with `spring.cloud.function.definition`.

What I would like to know is if there is a way to achieve the same function composition behavior when using classes, instead of function beans. For instance, this is how I would like to define the application's functionality:

```java
@Component
public class MessageValidator implements Function<String, String> {
    @Override
    public String apply(final String message) {
        // Validation logic
        return message;
    }
}
```

```java
@Component
public class FilterFunction implements Function<String, String> {
    @Override
    public String apply(final String message) {
        // Filtering logic
        return message;
    }
}
```

```java
@Component
public class ProcessFunction implements Function<String, String> {
    @Override
    public String apply(final String message) {
        // Processing logic
        return message;
    }
}
```

And then declare the order: `MessageValidator` > `FilterFunction` > `ProcessFunction`.

Is there a way to declare the functionality using these classes and have Spring Cloud Stream compose them in the same way it does with function beans? If so, how can I achieve this?