help java

Question

public class Auto
{
// instance variables - replace the example below with your own
String marka;
boolean wypozyczone;

/**
* Constructor for objects of class Auto
*/
public Auto(String marka,boolean wypozyczone)
{
// initialise instance variables
this.marka = marka;
this.wypozyczone = wypozyczone;
}
public Auto(String marka)
{
// initialise instance variables
this.marka = marka;
}

public static void main( String[] args )
{
// put your code here
Auto auto = new Auto("BMW", true);
Auto auto1 = new Auto ("Hammer", false);
Auto auto2 = new Auto("Mercedes");
Auto auto3 = new Auto("Opel");
System.out.println(auto + " 2: " + auto1 + " 3: " + auto2 + " 4: " + auto3);
}
}

1)Why the program shows me the next output:
Auto@4909b8da 2: Auto@3a03464 3: Auto@2d3fcdbd 4: Auto@617c74e5
2) Why the second constructors also show the boolean result if I declare only a String?

Answer 1

1. "Auto@xxxx" is a reference, you are actually trying to print whole object. If you want make it work this way you can override toString() method in Auto class.
2. I don't really understand

Answer 2

This code print the address (on memory) where your objects are stored.