When the block is declared without using any modifier, then it is treated as the non-static block is first executed before the constructor is executed. Non-static block directly access the static variable and instance variable.
Here is the Java Example for the program Non-Static Block:
public class NonStatic { NonStatic() { System.out.println("Dinesh"); } { System.out.println("Thakur"); } public static void main (String args[]) { NonStatic t1=new NonStatic(); } }