Unlock the Power of Command-Line Arguments in Java
Getting Started with Command-Line Arguments
When you execute a Java program, you can pass arguments through the command line, allowing for greater flexibility and customization. But how do you tap into this powerful feature?
A Simple Example
Let’s create a program that accepts command-line arguments. We’ll compile and run the code, passing in arguments like “apple”, “ball”, and “cat”. The output will reveal the magic behind command-line arguments.
Decoding the Main Method
The main() method, the entry point of every Java program, includes an array of strings named args as its parameter. This array stores all the arguments passed through the command line. Note that arguments are always stored as strings, separated by white spaces.
The Limitation of Numeric Arguments
While the main() method only accepts string arguments, you can’t directly pass numeric values through the command line. However, there’s a workaround. You can convert string arguments into numeric values using methods like parseInt(), parseDouble(), and parseFloat().
Converting Strings to Numbers
Let’s see an example where we pass numeric arguments, “11” and “23”, through the command line. The output will demonstrate how to convert these string arguments into integers using the parseInt() method. Similarly, you can use other parsing methods to convert strings into doubles or floats.
Beware of NumberFormatException
When converting string arguments to numeric values, be cautious of the NumberFormatException. This exception occurs when the arguments can’t be converted into the specified numeric value.
By mastering command-line arguments, you can unlock new possibilities in your Java programs. Experiment with different arguments and conversions to take your coding skills to the next level!