How to convert this code to java8 lambda

Question

I\'ve just started working with Java 8 and I\'m struggling with this code snippet:

paramsValues[idx++] = new ReplyMessage() {
    @Override         


        

Answer 1

If ReplyMessage is a functional interface, you could do

paramsValues[idx++] = reply -> message.reply(reply);

Here's a full example with stub implementations of the other classes in your question:

// Stub classes
class JsonObject { }

@FunctionalInterface
interface ReplyMessage {
    void reply(T jo);
}

class LambdaDemo {
    public static void main(String args[]) {

        // Dummy variables
        ReplyMessage message = new ReplyMessage() {
            public void reply(JsonObject jo) {}
        };
        ReplyMessage[] paramsValues = new ReplyMessage[5];
        int idx = 0;

        // Your code, lambdafied
        paramsValues[idx++] = reply -> message.reply(reply);

        // Or,
        // paramsValues[idx++] = message::reply;

        // But then you could perhaps do with just ...
        // paramsValues[idx++] = message;
    }
}