Eclipse IDE is a popular integrated development environment used by developers worldwide for software development. One of the key features of Eclipse IDE is its ability to run and debug Java applications through the use of command line arguments. Command line arguments allow developers to customize the behavior of their Java applications by passing arguments to the main method of the program at runtime.
In this article, we will explore how to set up and configure command line arguments in Eclipse IDE, so you can get the most out of this powerful feature.
Step 1: Create a Java project
The first step to setting up command line arguments in Eclipse is to create a Java project. To do this, go to File -> New -> Java Project. Give your project a name and click Finish.
Step 2: Create a Java class
Once you have created your Java project, you need to create a Java class. To do this, right-click on your project in the Package Explorer view, go to New -> Class. Give your class a name and click Finish.
Step 3: Add a main method to your class
Next, you need to add a main method to your class. The main method is the entry point for your Java application and is where you will receive the command line arguments. To add a main method, type the following code:
public class CommandLineArguments { public static void main(String[] args) { // TODO Auto-generated method stub System.out.println("Total Command Line Arguments " + args.length); for(int i = 0; i< args.length; i++) { System.out.println(args[i]); } } }
Step 4: Pass command line arguments to the main method
Now that you have set up the basic structure of your Java application, you need to pass command line arguments to the main method. To do this in Eclipse, go to Run -> Run Configurations. In the Run Configurations dialog box, select your Java application from the left-hand side and click on the Arguments tab.
In the Program Arguments field, enter the command line arguments you want to pass to your Java application. For example, if you want to pass three arguments, “Study”, “Trigger” and “Rocks!!”, you would enter:
If your program is not saved then a confirmation box will appear, just click “OK” on that confirmation box. Like :
Step 5: Run your Java application
Once you have configured your command line arguments, you can run your Java application. To do this, click on the Run button in the Run Configurations dialog box. Eclipse will launch your application with the specified command line arguments and you will see the following output :
Now, if someone wants to run command line arguments without Eclipse IDE, so, they are follows the following steps:
Step 1: Create a Java file in Notepad
The first step is to create a Java file in Notepad. Open Notepad by going to Start -> All Programs -> Accessories -> Notepad. Type the following code into the editor:
public class CommandLineArguments { public static void main(String[] args) { System.out.println("Command line arguments:"); for (int i = 0; i < args.length; i++) { System.out.println(args[i]); } } }
This code creates a simple Java class that prints out the command line arguments that are passed to it.
Step 2: Save the file with a .java extension
Next, you need to save the file with a .java extension. Go to File -> Save As, and choose a location to save the file. Name the file “CommandLineArguments.java” and choose “All Files” as the file type. Click Save.
Step 3: Compile the Java file using the command line
Now that you have created the Java file, you need to compile it using the command line. Open the command prompt by going to Start -> All Programs -> Accessories -> Command Prompt. Navigate to the directory where you saved the Java file using the cd command. For example, if you saved the file in the “C:\Java” directory, you would type:
cd C:\Java
Once you have navigated to the correct directory, type the following command to compile the Java file:
javac CommandLineArguments.java
This will compile the Java file and create a new file called “CommandLineArguments.class”.
Step 4: Run the Java file with command line arguments
Finally, you can run the Java file with command line arguments using the following command:
java CommandLineArguments arg1 arg2 agr3
Replace “arg1”, “arg2”, and “arg3” with the command line arguments you want to pass to the program. For example, if you want to pass the arguments “hello”, “world”, and “123”, you would type:
java CommandLineArguments Study Trigger Rocks!!!
This will run the Java program and print out the command line arguments you passed to it.
Conclusion
In conclusion, command line arguments are a powerful feature of Eclipse IDE that allow developers to customize the behavior of their Java applications. By following these steps, you can easily set up and configure command line arguments in Eclipse IDE and take full advantage of this feature. With a little practice, you can use command line arguments to create more flexible and powerful Java applications that meet your specific needs.