TransactionalMono.java

package com.odin.rating.application.utils;

import com.odin.rating.application.api.PersistenceHandler;
import reactor.core.publisher.Mono;

import javax.persistence.EntityTransaction;
import java.util.function.Function;

public class TransactionalMono<T> {
	private final EntityTransaction transaction;
	private final Mono<T> mono;

	private TransactionalMono(EntityTransaction transaction, Mono<T> mono) {
		this.transaction = transaction;
		this.mono = mono;
	}

	public static <T> TransactionalMono<T> just(PersistenceHandler db, T target) {
		return new TransactionalMono<>(db.beginTransaction(), Mono.just(target));
	}

	public <R> TransactionalMono<R> map(Function<T, R> function) {
		return new TransactionalMono<>(transaction, mono.map(function));
	}

	public <R> TransactionalMono<R> transform(Function<TransactionalMono<T>, TransactionalMono<R>> function) {
		return function.apply(this);
	}

	public T commit() {
		PersistenceHandler.commit(transaction);
		return mono.block();
	}
}