Optional Parameters in Java: 3 Methods With Codes Explained

Are you aware of the “Optional Parameters in Java“? With optional parameters, you can create methods that can easily handle various scenarios without affecting your codebase. Let us try to find out the methods to implement Optional parameters in Java along with some codes explained.

Still, if you have any questions related to optional parameters while solving your Java assignment then you can get Java assignment help online by hiring the proficient experts at CodingZap.

But before we start writing about the Optional parameters in Java programming language, we need to know about its background. Without clearing the background of Optional parameters in Java, you can’t able to get the complete topic.

So, let us start our discussion in a very basic interesting way.

What Are Java Optional Parameters?

Optional Java parameters are an important concept in the Java programming language. Functions work in any programming language with the help of some arguments. We have to pass some arguments to the function to work properly.

In a simple program, we know the number of arguments that needs to pass in a function. But in a long program or project, it is hard to find out the number of arguments needed in a function. If we provide less number of arguments, then the program will not execute.

There comes the need to implement Java optional parameters.

// Examples Of Function Calling With Arguments & Without Arguments
public class Main {
	static void ZapOne() { // Function Without Any Argument Mentioning
    		// Statements
	}
	static void CodingZap(int a, int b) { // Function With Two Int Arguments
    		// Statements
  	}
}

When we don’t know the number of arguments needed in a program, we mark some of the arguments as optional parameters. It helps to execute the code without having any errors even if there is a less number of arguments present.

We can relate the concept with the Array & Linked List. In Array, we can only store some particular number of items. But in the case of the Linked List, we can store an unlimited number of elements. You can remember this example to implement Java optional parameters.

What Are The Methods To Implement Optional Parameters in Java? Read Below

To implement Java optional parameters, there are several ways are present. Here, we are going to discuss three important methods to implement optional parameters in Java. But sometimes, you might find another way to implement optional parameters.

We will discuss those things later. Let us know the methods to develop optional parameters In Java.

• Optional Parameter Using Method Overloading
• Optional Parameter Using Optional Class
• Optional Parameter Using Variable Length Arguments (Varargs) Class

Let us try to find out all of them one by one briefly.

How To Develop An Optional Parameter Using Overloading?

Overview Of The Concept:

We all know about the Method Overloading concept in the Java programming language. Method overloading is a process by which one can call the same method where a different number of arguments need to be passed.

Now, you might be thinking what is the relation between the Method Overloading & Optional Parameter?

// Examples Of Method Overloading Process
public class Main {
	static void ZapOne(int a, int b) {} // Calling Function With Two Integers
	static void ZapOne(int a, int b, int c) {} // Calling Same Function With Three Integers
	static void ZapOne(int a, int b, string z) {} // Calling The Same Function With Two Integers & One String Parameter or Argument
}

Method overloading works on a simple optional parameter concept. Each & every function declared with the same name & a different number of arguments helps to fulfill the Optional Parameter concept. But there is one problem with it.

Suppose, you are assuming to get arguments up to 30 in one program. If you are going to follow this program, you need to implement 29 same methods with different numbers of arguments to execute the program properly.

Hence, it is a very tedious task to complete. We will give a remedy for this after looking at the example.

Write A Code To Develop Optional Parameters Using Method Overloading Process:

public class Main{
	public static void main(String arg[]){
		System.out.println("Function With Two Arguments: "+ Zap("Zap", "One")); // Calling Function With Two Argument
		System.out.println("Function With Three Arguments: "+ Zap("Hello","Zap", "One")); // Calling Function With Three Argument
		System.out.println("Function With Four Arguments: "+ Zap("Hello", "Java", "Zap", "One")); // Calling Function With Four Argument
	}
	public static String Zap(String a, String b){ // Original Function With Two Argument
		return a + b; // Doing Operation
	}
	public static String Zap(String a, String b, String c){ // Java Overloading Method For Optional Parameter
		return a + b + c; // Doing Operation
	}
	public static String Zap(String a, String b, String c, String d){ // Java Overloading Method For Optional Parameter
		return a + b + c + d; // Doing Operation
	}
}

Steps Of The Program to find out the implementation process of the Java optional parameters:

1. Let the program start with the basic implementation of the Public Static Void Main method.
2. Inside that method, we are going to call the same method one by one with a different number of arguments. The number of arguments will be two, three & four for different cases.
3. Now, we will implement the functions one by one with a certain number of arguments. it is going to develop Java optional parameters in the program.
4. Now, inside the functions, we are going to do some random work. In the above example, we are going to concatenate the string args & returning the value.
5. Hence, the Method Overloading will help to develop Java optional parameters in this program.

Let us try to find out the output of the above example. It will help to find out the implementation process of the Java optional parameters.

Output:

What Is The Way To Develop An Optional Parameter Using An Optional Class?

Overview Of The Concept:

Now, an issue that we are facing in the above example will be cleared with the help of the optional class method. It is the proper method to develop Java optional parameters in the program. The optional class implements the optional container object in the program.

This optional container object can able to recognize how many arguments one has given in other functions. Suppose, in one case, you need to call a function with four parameters & in another case, you need to call the same function with only one parameter.

// Example To Implement Optional Object
public class Main {
	static void ZapOne(argument1, argument2){
	// Implementing Optional Parameter Among Other Arguments
	Optional var = Optional.ofNullable(argument-which-should-be-optional);
	// Other Statements
}}

With the help of the optional container object, the purpose will be fulfilled. One needs to provide the null values as the remaining arguments to the method. In that case, the program will execute without any error causing.

In the above case, the private string first name & private string lastname has been taken as the arguments to the function. And based upon the private string lastname, the optional container object has been created. Check out our article, if you’re looking for methods to convert an object to an integer in Java.

We will know more about it in the below example.

Write A Code To Develop Optional Parameters Using Optional Object:

import java.util.Optional; // Importing Necessary Package
public class Main{
		public static void main(String args[]){
			check("Zap","One"); // Normal Function Calling
			check("Java",null); // Function Calling With Null Value
    }
    private static void check(String a, String b){ // Implementation Of User Defined Method & Calling String Firstname & String Lastname
        Optional<String> b1 = Optional.ofNullable(b); // Creatung Optional Object & Making b (string lastname) Optional 
        String o = b1.isPresent() ? b1.get() : "Data Is Not Present"; // Checking Presence Of Optional Data & not making any harm to string a (string firstname)
        System.out.println("First Data: "+ a + " & Last Data: "+ o); // Providing Value
    }
}

Steps Of The Program to find out the development process of the Java optional parameters:

1. The implementation of the program will be started from the Public Static Void Main function.
2. Inside the function, we will call one function with two different argument types. In one case, both arguments will be provided. And in the other case, the second argument will be the Null value.
3. Now, one private or public static nested class will be developed inside of the program where the optional builder class will be called. It is going to create Java optional parameters. Static keyword plays an important role in Java, but it is also used in C++ as well. If you’re curious to know more about static functions in C++, then you can check out our article.
4. The second string will be tagged as the Null value in the program. We will do nothing with the private string firstname inside of the program.
5. Now, we will check the presence of the data inside of the second argument in the optional builder class. If there is value, the value will be provided. Else, the default values will be implemented inside the program.
6. Now, using both default values means the private final string will be printed in the program.

Let us try to find out the output of the above example. It will help to find out the development process of the Java optional parameters.

Output:

From the above output, we can see that the function is working properly. The Null value is considered by the program & the default value will be printed. Hence, the output is correct.

How  To Develop An Optional Parameter Using Variable Length Arguments (Varargs) Class?

Overview Of The Concept:

The Varargs method or the Variable Length Arguments method is another method that helps to develop Java optional parameters in the program. In this implementation process, one can share zero to an infinite number of arguments to the program.

The implementation process might bring a big smile to your face because it is the easiest implementation process. The development process might start from the Public static void main function. But the real hero is the Varargs class.

// Example To Develop Varargs Class
public class Main {
	public static void ZapOne(datatype...variable){ // Declaration Of Varargs
		// Statements
}}

If you consider it to be one of the easiest methods, then you should be aware first. Using the Varargs method to develop Java optional parameters will be a fatal decision one can make.

It might seem an easy method, but there are a lot of chances to get any random error message from the compiler. So, try not to use this method much for implementing Optional parameters in the Java programming language.

Write A Code To Develop Optional Parameters Using Varargs Class:

public class Main{
	public static void main (String args[]){
		Varargs.data(); // Function Calling With No Argument
		Varargs.data("Zap", "One"); // Function Calling With Some Arguments
    }
}

class Varargs { // Implementation Of User Defined Class
	static void data(String... input) { // Implementation Of Varargs Function
		String a[] = input; // Taking Input
		System.out.println("Number Of Argument Shared: "+ a.length); // Printing Function 
    }
}

Steps Of The Program to find out the use of Varargs in the Java optional parameters development process:

1. In this program also, the implementation process will be started from the Public static void main function.
2. Inside the Public Static Void Main function, the Varargs function will be called to develop the optional parameters.
3. In one case, we should provide some argument value while calling it. In another case, we will call the function without any argument value.
4. Now, the implementation of the Varargs class will be done. And according to the syntax value, the implementation of the function will be completed.
5. Now, inside that function, we will take the inputs in the string variable. One by one all the values will be stored there.
6. These are the values that will be used for printing purposes. We can get the number of inputs we have provided to the class.

Let us try to find out the output of the above example. It will help to find out the use of Varargs in the Java optional parameters development process. Many students get stuck while comparing strings in Java so we have written a detailed article on it and learned how to implement it.

Output:

The above output shows that the function called without any arguments can’t able to show any output. On the other hand, the function where some arguments are passed, it is giving the output. So, the Optional Parameters are correctly developed in the program.

Conclusion:

As we saw it is very important to know the implementation process of Optional Parameters in Java program.

Optional parameters are the major key elements to deal with a large number of arguments where you don’t know the number of parameters involved in the function. So, we should get a nice grip on all the methods demonstrated above.

It is advisable to clear the basic Java programming concept before moving to the Optional parameters topic. If the basic concept is not clear you might find some of the development processes as a challenging task. Remember, the Optional parameters are the solution to all major problems that will come in the future.