Thread: Cannot print name, getting null error.

Firstly thanks taking the time to help me out.

I can compile and run this program but where I want to print the Dogs name and age (with the toString method) it prints only the age, returning "null" for name.

//Dog.java
//represents a dogs age and name and contains methods to do several
//things.
 
public class Dog
{
  private String name;
  private int age;
 
  //constructor: initializes the instance data name and age:
  public Dog ()
  {
  age = 14;
  }
 
  //getter
  public int getAge ()
  {
    return age;
  }
 
  //setter
  public void setAge (int value)
  {
    value = age;
  }
 
  //getter
  public String getName ()
  {
    return name;
  }
 
  //setter
  public void setName (String words)
  {
    name = words;
  }
 
  //toString method
  public String toString()
  {
    return name + "\t" + age;
  }
}

and the driver class:

//Kennel.java
//main method instantiates and updates several Dog objects.
 
public class Kennel
{
  public static void main (String[] args)
  {
 
  Dog Scruffy, Jade;
 
  Scruffy = new Dog ();
 
  Scruffy.getName();
 
  System.out.println ("Scruffys age in human years: " + 
  Scruffy.getAge());
 
  System.out.println (Scruffy);
  }
}

and when running the program i get:

craig@craig-laptop:~/Documents/panda/java2$ java Kennel
Scruffys age in human years: 14
null	14

I want the dogs name to show as 'Scruffy'.

I've tried editing the constructor to this:

  //constructor: initializes the instance data name and age:
  public Dog ()
  {
  name = Scruffy;
  age = 14;
  }

But it doesnt compile:

craig@craig-laptop:~/Documents/panda/java2$ javac Dog.java
Dog.java:13: error: cannot find symbol
  name = Scruffy;
         ^
  symbol:   variable Scruffy
  location: class Dog
1 error

And i've also tried putting the name in at with the data declarations:

public class Dog
{
  private String name = Scruffy;
  private int age;

But that gives an error too:

craig@craig-laptop:~/Documents/panda/java2$ javac Dog.java
Dog.java:7: error: cannot find symbol
  private String name = Scruffy;
                        ^
  symbol:   variable Scruffy
  location: class Dog
Dog.java:13: error: cannot find symbol
  name = Scruffy;
         ^
  symbol:   variable Scruffy
  location: class Dog
2 errors

Ok I've got scruffy sorted
Now im trying to make a new dog Spot by doing this:

 Spot = new Dog ();
 Spot.setName (Spot);

but get error:

craig@craig-laptop:~/Documents/panda/java2$ javac Kennel.java
Kennel.java:19: error: method setName in class Dog cannot be applied to given types;
  Spot.setName (Spot);
      ^
  required: String
  found: Dog
  reason: actual argument Dog cannot be converted to String by method invocation conversion
1 error

I know im doing something stupid here but I dont know what. How do should I create a new Dog object and declare its name as spot?

--- Update ---

I have this now at the top of the Dog class:

public class Dog
{
  private String name;
  private int age;
 
  //constructor: initializes the instance data name and age:
  public Dog ()
  {
  name = "Scruffy";
  age = 14;
  }

But I want the name variable to change for every new Dog object I create. Is that going to happen or is it going to try and call every new dog "Scruffy" ?

Ok I have this sorted now Norm. Thanks for your help.