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I want to create a method that accepts something like this

set(nodeStatus, status, NodeStatus::setStatus, Status::valueOf);
set(nodeStatus, errorCode, NodeStatus::setErrorCode, ErrorCode::valueOf);

Status and ErrorCode are enums in java.

Signature and pseudocode

set(NodeStatus nodeStatus, byte[] status, ?nodeStatusOperator , ?ValueTransformer) 
 1. convert byte[] status to appropriate value as per ValueTransformer
 2. nodeStatusOperator sets this transformed value according to the lambda passed.

I want to know what method signature should be used to accompalish this in java and why. I tried various Consumers, BiConsumers etc but couldnt do this. Can anyone please help?

As far as I can tell, what you need is this:

public <T> void set (NodeStatus nodeStatus, 
 byte [] value, 
 BiConsumer<NodeStatus,T> setter, 
 Function<byte[],T> transformer) 
 T transformedValue = transformer.apply(value);
 setter.accept(nodeStatus, transformedValue);

(If value can be something other than byte[], you can replace it with another type parameter.)

P.s.: setter is a BiConsumer, because you use a static method reference (e.g. NodeStatus::setErrorCode) on an instance method, so the first argument of BiConsumer has to be the NodeStatus instance setErrorCode() will be called on.

P.p.s: As pointed out by glglgl, you can potentially simplify your code to this:

public <T> void set (byte [] value, 
 Consumer<T> setter, 
 Function<byte[],T> transformer) 
 T transformedValue = transformer.apply(value);
 setter.accept(transformedValue);

And call it like this:

set(status, nodeStatus::setStatus, Status::valueOf);

...where nodeStatus is the instance of NodeStatus you want to manipulate.

It's a little unclear what you're trying to achieve. Why pass the NodeStatus and the function when you could just pass a function that works on that specific NodeStatus instance, e.g.:

static <T> void set(byte[] status, Consumer<T> nodeStatusOperator, Function<String, T> transformer) 
 nodeStatusOperator.accept(transformer.apply(new String(status)));


public static void main(String[] args) 
 NodeStatus nodeStatus = new NodeStatus();
 byte[] status = new byte[0];
 set(status, nodeStatus::setStatus, Status::valueOf);
 set(status, nodeStatus::setErrorCode, ErrorCode::valueOf);

And what does that genericity buy you over a more straightforward approach?

nodeStatus.setStatus(Status.valueOf(new String(status)));
nodeStatus.setErrorCode(ErrorCode.valueOf(new String(status)));