The present era is of a hectic lifestyle and a short attention span. This makes slow code a nightmare for developers. The irony is that even Java, one of the most efficient technologies, is prone to this fallacy.
But, it also provides an easy way out of this problem. We can use memorization for the frequently used functions.
What is Memorization?
Memorization in Java works just like memory does in human beings. When we do something frequently like (saying an answer aloud), our brain tends to memorize it without actually referring to the source.
Likewise, memoization caches the function carried out multiple times. So it presents the answer without actually carrying out the actual function. It reduces the time taken as they do not execute every single time.
Memorization can also be used for recursive functions as it reduces the time taken. The ideal situations where you can use memorization are:
- The best use of memorization in Java is for the recursive functions or the functions that recall themselves.
- Expensive functions takes up too much time, it can slow the performance but, memorization will save time.
- We can only use memorization for the pure functions that always yield the same results.
How Memorization Works?
Whenever you have to deal with an expensive function that slows down your code, Memoization can be an easy way out. It will return the same results without actually executing the actual function to save time.
We can understand it with different example.
Let us consider a function where we treat a number as an argument such that it returns the square of the number in the result.
Here, ordinary we use the following code and, it will always return the same value. It happens each time you perform the function.
But it is time not efficient as it takes a lot of time, making memorization a smart alternative. So, when the program first executes clumsy square() we will store its value and then use it multiple times. Consequently, it will carry out the function faster when called the next time.
Using a Memorized Function
If we run the code multiple times and test its performance, we will see that the time of its execution will decrease. The output will look like something like this:
Any discussion about memorization can not be complete until we talk about its two sub-concepts. These constitute:
It refers to a combination of a particular function that is bundled with the references within its lexical environment in the in its surrounding state.
High Order Function
It refers to the functions that accept functions as parameters to return a function.
The best use of memorization is in recursive programs viz the programs that call themselves and form the concept of looping. But the looping element should also have a condition that will put an end to the loop.
The best example is the Fibonacci sequence where every third term is the sum of the first two terms.
This is how it creates the pattern:
Here, we are calculating the same numbers each time, making it a redundant computation.
Although the computation is initially straightforward, the program will become slower as we increase the terms.
Alternatively, we can memorize the function to reduce the time it will take. It will cache every function so that it does not have to repeat itself.
Memoization appears to be a good option for all the heavy functions, but be careful about their usage as it also takes up space in the memory.
Also, if you are using APIs, memoization might not be required as the browser will automatically do that for you.
It is easy to get confused between memorization and caching. Be mindful that caching refers to any storing technique. Memoization, on the other side, deals with the return values of the function.
So the next time you are thinking about the accurate use of Memorization in Java, we hope this guide by our experts comes in handy to you.