How can I solve this java problem?

[babs115]

ERROR MESSAGE[non-static variables this cannot be referenced from a static contex ]
public static void main(String []args)

{ 
  Product p = new Product(110,"Books",15.00,2010,"Wiliams");
  p.setproductId(110);
  p.setproductName("Books");
  p.setCost(15.00);
  p.setyearOfPublication(2010);
  p.setpublishingHouse("Wiliams");
 
 
  int productId = p.getproductId();
  String productName = p.getproductName();
  double cost = p.getCost();
  int yearOfPublication = p.getyearOfPublication();
  String publishingHouse = p.getpublishingHouse();
 
}
class Product
{
   private int productId;
   private String productName;
   private double cost;
   private int yearOfPublication;
   private String publishingHouse;
 
 
public Product(int productId,String productName,double cost,int yearOfPublication,String publishingHouse)
{
   this.productId = productId;
   this.productName = productName;
   this.cost = cost;
   this.yearOfPublication = yearOfPublication;
   this.publishingHouse = publishingHouse;
}
 
public void setId(int productId)
   {
     this.productId = productId;
   }
 
public int getproductId()
   {
       return productId;
   }
public void setproductName(String productName)
   {
     this.productName = productName;
   }
 
public String getproductName()
   {
       return productName;
   }
 
   public void setcost(double cost)
   {
     this.cost = cost;
   }
 
public int getcost()
   {
       return cost;
   }
 
   public void setyearOfPublication(int yearOfPublication)
   {
     this.yearOfPublication = yearOfPublication;
   }
 
public int getyearOfPublication()
   {
       return yearOfPublication;
   }
 
   public void setpublishingHouse(String publishingHouse)
   {
     this.publishingHouse = publishingHouse;
   }
 
public int getpublishingHouse()
   {
       return publishingHouse;
   }
}
 
class Book extends Product
{
 private String author;
 private int ISBN;
 private int numberOfPages;
 
 
public Book(String author, int ISBN, int numberOfPages, int productId, String productName, double cost,
              int yearOfPublication, String publishingHouse)
    {
     super(productId,productName,cost,yearOfPublication,publishingHouse);      
     this.author = author;
     this.ISBN = ISBN;
     this.numberOfPages = numberOfPages; 
    }
}
 
class Software extends Product
{
 private int RAM;
 private int processor;
 
 
 
 public Software(int RAM,int processor,int productId, String productName, double cost,
                  int yearOfPublication, String publishingHouse)
     {
         super(productId,productName,cost,yearOfPublication,publishingHouse);      
         this.RAM = RAM;
         this.processor = processor; 
     }
 
 
}
 
}

[chaarmann]

I can't see any error here regarding static and non-static calls. Which line is the error? Maybe you forgot to include the line containing the error in this listing?)

[Kara Hewett]

You don't identify the static versus non-static methods except that the java main function is static by design. If you are calling the Product class within the java main function, then that could be a problem. Try making Product a standalone class such as Product.java. Then in the java static main method instantiate the class, e.g. Product p = new Product();