Void is not allowed here (GUI Netbeans)

Question

I am trying to use the inheritance concept where I inherit my data from the super class using GUI in Netbeans. I want the button in the form to display the information i got from the super class. However,i am getting the 'Void cannot be allowed' error. Can you help me solve this?

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
         House myHouse = new House(8);
         JOptionPane.showMessageDialog(null,myHouse.displayHouseDetails());
    }

UPDATE

public class Building {

protected String size;
protected double price;

public Building(String size,double price)
{  this.size = size;
  this.price = price;
 }

}

public class House extends Building{
private int houseNo;

  public House(int houseNo)
  {  super("100 X 90",100000);
     this.houseNo = houseNo;
  }
public void displayHouseDetails(){  

     System.out.println("House no:"+houseNo);
     System.out.println("Size:"+size);
     System.out.println("Price:"+price);   
     }

btw, may I know how can i make my button to display the data that inherit from super class?

You did not provide us where exactly it gave the error and slo we have no clue as to what the definition of `House` is. — Neijwiert, Nov 23 '15 at 15:21

Neijwiert · Answer 1 · 2015-11-23T17:41:00.913

1

public void displayHouseDetails() returns void and may not be used as an argument in another function.

It should be:

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
     House myHouse = new House(8);
     myHouse.displayHouseDetails();
}

Or make a concatenated string in the function and return that.

btw, may I know how can i make my button to display the data that inherit from super class?

Change displayHouseDetails to:

public String displayHouseDetails(){  
    StringBuilder builder = new StringBuilder("House no:");
    builder.append(houseNo).append(System.lineSeparator());
    builder.append("Size:").append(size).append(System.lineSeparator());
    builder.append("Price:").append(price).append(System.lineSeparator());

    return builder.toString();
 }

edited Nov 23 '15 at 17:41

answered Nov 23 '15 at 15:37

Neijwiert

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What i meant by that is that I;m trying to build a program with GUI where when i click the button, it will display all the information that i get from Building class – Miru Nov 23 '15 at 15:43
1

upvote for using strinbuilder, also small note:) http://stackoverflow.com/questions/247059/is-there-a-newline-constant-defined-in-java-like-environment-newline-in-c – HRgiger Nov 23 '15 at 17:37
@HRgiger +1 for `System` constant. – Neijwiert Nov 23 '15 at 17:41

Void is not allowed here (GUI Netbeans)

1 Answers1