What does public static <X> void main(String[] args)
stand for? I tried to understand but didn't get. I know about public static void main(String[] arg)
. Thanks in advance.
Let's look at each bit in turn:
public
- it's a public method, accessible to anything which has access to the class in which this is declared <X>
- this is (somewhat bizarrely) a generic method with an unbound type variable X
static
- the method is related to the type in which it's declared, not any specific instance of the type void
- the method doesn't return a value main
- the name of the method String[] args
- a single parameter, of type String[]
and called args
main
is the entry point used by the JVM. When you run:
java foo.bar.Baz
it will try to find a main
method in class foo.bar.Baz
. I've never seen a generic main
method before, admittedly. For more about generics in Java, read the Java Generics FAQ .
<X>
is known as Type Parameter .
This is applicable to the methods, classes, variables, etc.. But its most important use is to make the Collections more type safe.
<X>
will mark a certain Type within the main()
method.
The whole sentence dissection is as follows:
public
- is the access-modifier, means that this method is accessible from anywhere. <X>
- Type Parameter, as mentioned above void
- This method will not return anything main
- Method's name, main() method is the entry point of any pgm in java. String[]
: Array Of String. args
: Array reference variabl of type String.
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