Do you know how to throw an exception in Java? Have you ever thought about the Java throw exception process? Well, if you want to get Java Project help and want to learn about throwing exceptions in Java then this article is for you.
Let us try to understand the theory of exception in Java. Also, we will try to understand the implementation process of exceptions in Java with example.
But before we start writing about Java throw exception & implement exceptions in Java with example, we need to clarify the basic concept. We need to first analyze the topic with the help of one daily life example. This will help to understand how to throw an exception in Java.
Let us assume one scenario.
Real-life Example:
Suppose, you belong to a group in your school. Your teacher provided you with a task to implement a project in any certain domain. Now, you are not familiar with that domain. But you need to implement the project & help others in their task. You started gathering knowledge about the domain & project. And you started working on that.
But you have already told your teacher that in any case, if there is any difficulty you can ask for help from your teacher. Now, after working there for 2 months, you face one problem. You can’t have a way out of that case. So, what will you do in such a case? Will you stop working on the project?
As you have already asked your teacher to help you whenever there is a need. So you will directly ask your teacher for help. And your teacher will help you to come out of that situation. So, this is the exception case, you have committed to the project.
A similar exception might arise in the Java programming language. Java throw exception will help us to sort out the such situation. We will know more about this further when we discuss exceptions in Java with example. But before let us know more about the exception process in Java & then we will discuss how to throw an exception in Java.
What Is An Exception In Java Programming Language? Read Below
Before we start writing about how to throw an exception in Java, we need to first understand the exception in Java. The exception is a feature present in the Java programming language. It is a feature that is not only present in the Java programming language. But this feature is present in all Object-Oriented Programming Languages. So, the C++ programming language also has some exception policies. These are the policies that help to write down the code in a very simple way. Learn more about exception handling in C++.
The exception is a well-known situation in the programming language. In any programming language, there might be a chance of occurring an Exception. Suppose, in a program, a number is going to be divided by any random number. Then there might be an exception. As if the random number comes as Zero, division is not possible. And the program will be terminated. So, this type of situation might not occur in Java throw exception process. We will discuss more exceptions in Java with example.
How To Throw An Exception In Java programming language? Get To Know
Now, it is time to discuss how to throw an exception in Java. In Java programming language, an exception can be handled using two possible ways. In one case, we previously know about the exception that is going to be happening. And in one case, we use different exception methods to catch any one of them, if occurs. Also, if you want to know about methods to reverse list in Java then you learn more about reverse a list in Java.
So, let us make a list of the process by which we can handle exceptions in Java:
- Using Try-Catch Process
- Using Throw Process
We will find out all the processes related to the Java throw exception. But before we start to know more about them, we need to first know the different types of exceptions present in the Java programming language. Then we will know each & every exceptions in Java with example. So, let us move towards that topic, and then we will discuss how to throw an exception in Java programming language.
What Are The Categories Of Exceptions In Java Programming Language?
In Java programming language, there are lots of exceptions are present. Each & every exception point out a certain issue in the programming. Though, there are many exceptions are present in the Java programming language, but still they can be categorized into different groups. Their working principle helps to divide them into some categories. These categories are related to the Java throw exception process.
Also, the categories can be divided into sub-categories. These categories help to define exceptions in Java with example. Let us make a list of the possible exceptions present in the Java programming language:
- Checked Exceptions: These are one type of exception that belongs to the inbuilt exceptions in the Java programming language. When a program is being executed using the Java programming language, some exceptions are being checked at the Compile Time of the program. These exceptions belong to that category. Now, there are several more sub-categories present in this group of exceptions. We will discuss them when we move to how to throw an exception in Java. Now, let us have a look at them.
- ClassNotFoundException
- InterruptedException
- IOException
- InstallationException
- SQLException
- FileNotFoundException
- Unchecked Exceptions: These exceptions also belong to the inbuilt exception category in the Java programming language. It is not similar to the Checked Exception in the Java programming language. As these exceptions are being checked at the Runtime of the program. When the program is compiled, then these exceptions are not checked. At the running time of the Java program, they are checked. That is the reason; these exceptions have the power to stop the execution of the whole program. This exception category also has some sub-categories. We will discuss them when we move to how to throw an exception in Java. Now, let us have a look at them.
- ArithmeticException
- ClassCastException
- NullPointerException
- ArrayIndexOutOfBoundsException
- ArrayStoreExceptions
- IllegalThreadStateException
How To Throw An Exception In Java Programming Language?
Now, as we all know the basic of the Java throw exception, we can all move to how to throw an exception in Java programming language. Here, we also discuss the implementation process of exceptions in Java with example. Many students also stuck while doing exponents in java so we have written a detailed article on How to do exponents in Java and it’s implementation. For the time being, you don’t need to worry about the Java throw exception category that we mentioned earlier. With more & more practice, you will get all the knowledge related to that field.
Here, we intend to demonstrate a total of four exceptions in Java with examples. Among them, two will be from the Checked Exception category & two will be from the Unchecked Category. Among those two examples, one will be using the Try-Catch Block. And another two will be using the throw keyword. So, without much wasting time, let us start our journey to get knowledge on how to throw an exception in Java programming language.
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How To Throw An Exception In Java Using Try-Catch Block?
Example 1: Checked Exception:
One thing we should remember is that the try-catch block can only able to handle unchecked exceptions. Their natural ability is to work with unchecked exceptions. But that doesn’t mean that the try-catch block can’t be used in the checked exceptions. We will learn more about this in this example when we discuss how to throw an exception in Java using a try-catch block for checked exceptions.
Here, we are demonstrating the example with the help of FileNotFoundException. Here, we have taken one file name. That file name shouldn’t be present in the file section of the Java programming language. Now, we need to access the file in that program. It is a simple operation that is executed. You need to have a basic understanding of file handling in Java. Now, this part should be in the Try block. As it might not be present there.
Now, we need to use the catch block. After the catch, we have written the exception type. And inside the catch file, we are just printing the exception that is caught there. In this way, we can successfully terminate our program without getting an error.
Example:
import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; public class Main { public static void main(String[] args) { String fileName = "ZapOne"; // Providing The File Name File file = new File(fileName); // Accessing The File try { FileInputStream stream = new FileInputStream(file); } catch (FileNotFoundException e) { // Try-Catch Block System.out.println("Exception Category: "+e); // Exception Type Print } }
Let us understand the output of the above code. It will help to understand how to throw an exception in Java programming language using a try-catch block for checked exceptions.
Output:
Example 2: Unchecked Exception:
Now, we have to use the try-catch block for the unchecked exceptions. As we know the unchecked exception is the natural field where the try-catch block can easily be implemented. As we already get knowledge of the implementation of the try-catch block in the checked exception, it is time to move forward. We will learn more when we discuss how to throw an exception in Java using a try-catch block for unchecked exceptions.
In this case, there is no need to import some packages. As it is natural policy to use a try-catch block in the unchecked exception, so there is no more formality needed. We will directly implement a try block. Inside that try block, we will put some arithmetic issues. Like, here we want to dive into any number using zero. Now, we will use the catch block to get the error & print it. It is most likely a similar process to the previous one.
Example:
public class Main{ public static void main(String[] args) { try { int data=1/0; }catch(ArithmeticException e){ // Try-Catch Block System.out.println("Exception Category: "+e); } System.out.println("This Line Will Be Executed..."); // Exception Type Print }
Let us understand the output of the above code. It will help to understand how to throw an exception in Java programming language using a try-catch block for checked exceptions.
Output:
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How To Throw An Exception In Java Using Throw Process?
Example 1: Checked Exception
The throwing process is completely the reverse of the try-catch block. The throwing process naturally goes with the checked exceptions. The throw keyword is mainly used for the checked exceptions process. For the implementation of the throw keyword in the checked exception, there is no need to use a difficult approach. We will learn more when we discuss how to throw an exception in Java using the throwing process for checked exceptions.
Here, we are discussing one simple example. The goal of the program is nothing but to print one statement. But our focus should not be on that. As that is not our intention. Here, we have declared the throws keyword after the main method in the program. After the throws keyword, we have added one line. This is the exception that is going to be occurring in this program.
Though this is a simple program, still there is a special line present in the program. The first line will forcefully sleep the process for some time. The thread.sleep() method can’t be implemented simply. It falls under that particular exception. That is the reason; we have added the exception name there. Otherwise, the program will not run.
Example:
public class Main{ public static void main(String[] args) throws InterruptedException // Throwing An Exception { Thread.sleep(100); // Statement That Need To Throw An Exception System.out.println("Line Printed: ZapOne Is Great"); // Printing Simple Statement }}
Let us understand the output of the above code. It will help to understand how to throw an exception in Java programming language.
Output:
Example 2: Unchecked Exceptions:
Now, we have to use the throwing process for the unchecked exceptions. As we know the checked exception is the natural field where the throwing process can easily be implemented. As we already get knowledge of the implementation of the throwing process in the checked exception, it is time to move forward. We will learn more when we discuss how to throw an exception in Java using the throwing process for unchecked exceptions.
It is a simple example provided here. We have provided a value to one variable. Now, we have declared one condition checking if statement. Under that block, we have written an Arithmetic Exception class. Along with that, there is a message provided with that exception. Now, if this program is executed the output will show up the exception type along with the message. In this way, we can use the throwing process in the unchecked exception.
Example:
public class Main { public static void main(String[] args) { int mark = 40; // Variable Declaration if (mark <= 50) { // Condition Checking throw new ArithmeticException("Marks Is Very Less...Unsuccessful"); }}}// Exception Occuring
Let us understand the output of the above code. It will help to understand how to throw an exception in Java programming language.
Output:
Conclusion:
As we saw, it is very important to understand how to throw an exception in Java programming language.
We need to first understand the exception policy of the Java programming language. Also, we need to know all the possible exceptions that might occur in the program. It is the process that is used in the projects implemented by the Java programming language.
It is advisable to clear the basic concept of the Java programming language. Without it, you will face issues while understanding this topic. After that, we can go through this topic to gather more knowledge. This is a very important topic. This will help us in the future. So, we need to practice this topic as much as possible.
So, hope you have liked this piece of article. Share your thoughts in the comments section and let us know if we can improve more.
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