Is the initialization of a variable a statement or an expression?

class Demo {
     public static void main(String[] args) {
          int a; // declaration statement

          a = 5; // initialization statement/expression?
     }
}

I've looked into it, and it seems to be both a statement AND an expression. Is this true? Is there any documentation on this?

A local variable declaration - with or without initialization - is a statement, as specified in section 14.4 of the JLS.

It's important to note that this is not an expression in the way that a simple assignment expression is - you can't use it as part of a larger statement (other than a block). For example:

int x;
System.out.println(x = 5); // Prints 5

System.out.println(int x = 10); // Invalid

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