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Why do we always pass String args in main method?
The String[] args parameter is an array of Strings passed as parameters when you are running your application through command line in the OS. The java -jar command will pass your Strings update and notify to your public static void main() method.
How can arguments be passed from the command-line into your program?
Command line arguments are passed to the main() method. Here argc counts the number of arguments on the command line and argv[ ] is a pointer array which holds pointers of type char which points to the arguments passed to the program.
What happens if a method does not have arguments in Java?
Without them, the JVM would have to perform a check to see if the method contains arguments before attempting to call the method, determining whether it could do main () or main (args) (two syntactically correct methods with different ways to call them) In Java the entry point has to be a public static void main (String []) method.
How to write the main method with arguments other than string?
You can write the public static void main () method with arguments other than String the program gets compiled. Since the main method is the entry point of the Java program, whenever you execute one the JVM searches for the main method, which is public, static, with return type void, and a String array as an argument.
Can we use array as argument in main method in Java?
Therefore, if you write a method with other data types (except String array) as arguments, at the time of execution, JVM does not consider this new method as the entry point of Java and generates an error. In the following Java program, we are trying to use an integer array as arguments of the main method.
Why are command line arguments in Java always in strings?
Also, command line arguments are Strings which is why that is the data type. Collections did not exist in Java 1 so they were not an option. Arrays did exist. Because by passing String arrays, we can pass all the necessary parameters like options/arguments related to the program in the form of String easily.