//filename Gg.java
public class Gg{
  public static void main ( String[] args ) {
    ...
  }
}

import java.util.Scanner; // program uses class Scanner
Scanner input new Scanner(System.in);
number1= input.nextInt ();

System.out.print()
System.out.println()
System.out.printf( format , ...)

int number1;

public class G {
  public static void method (){
    ///code
  }
}
public class caller {
 public static void main (String[] args){
   G gc = new G();
  gc.method();
 }
}

public class G {
  private String ss;
  public G (String str){
    ss =str;
  }
}

//
G h = new G("text");
....

if ( condition )
{

}

else if ( .. )
{
}

else ( ... )
{
}

cond > 6 ? 7 : 8 ;


a > b
a >= b
a <= b
a == b

if (1)
  if (2)
    aaa
  else
   bbbb

List<Obj> list = new ArrayList<Obj> (); 
//--------------------------
List<Integer> l1 = new ArrayList<Integer>();