Same doubt again regarding constructors

[Narayana.Vaddi]

  class Sup{
    public Sup(String str){
        System.out.println("Super class");
    }
}
 
public class Test2 extends Sup{
      public Test2(){
            System.out.println("Sub class");
      }
      public static void main(String[] args) {
            Test2 t2 = new Test2();
      }  

I am facing the following error when i try to compile the above code please reply me with the correct solution:


java.lang.NoSuchMethodError: main
Exception in thread "main"

[Alex Belisle Turcot]

Hi,

I can see you followed my advice with the "Code" tag
However, I answered your question in your first post

Please check your first post.

Regards,
Alex

[Narayana.Vaddi]

I complied the piece of code editted by you but still i'm facing the same error!!

[Jart Bo]

Hello Naranaya,

Welcome to Javaranch! First of all, you will need to check out the Javaranch policies regarding names.

You're missing a close parenthesis. Here's your correct code:

 
class Sup
{
public Sup(String str)
{
  System.out.println("Super class");
}
}
 
public class Test2 extends Sup
{
public Test2()
{
System.out.println("Sub class");
}
public static void main(String[] args)
{
Test2 t2 = new Test2();
}
}
 

You need to name your source code Test2.java because your Test2 class is coderanch. Now, I compiled it and it returned:
cannot find symbol
symbol: constructor Sup()
location: class Sup

It's because in your Sup class, you declared a constructor with argument, so effectively, Java will no longer insert a default constructor (a constructor without argument) in your Sup class. Now, when you're compiling Test2.java, there is an implicit call to super under your Test2 Constructor:

   
 
public Test2()
{
             [B]super();[/B]
System.out.println("Sub class");
}
 
 

And this is looking for a constructor under Sup with no arguments in it, which you don't have.

Here's the correction:

  
 
class Sup
{
public Sup(String str)
{
  System.out.println("Super class");
}
 
     [B]public Sup()
{

}[/B]
}
 
public class Test2 extends Sup
{
public Test2()
{
System.out.println("Sub class");
}
public static void main(String[] args)
{
Test2 t2 = new Test2();
}
}
  

[Narayana.Vaddi]

Sorry for again disturbing you but,still i am facing the forllowing error:


Exception in thread "main" java.lang.Error: Unresolved compilation problem:

at Test2.main(Test1.java:12)

[Narayana.Vaddi]

Ya i identified my problem now,i created another class Test1 and extended Test2,while i am trying to run the Test2 class,the Test 1 is effected,and the changes what i did is didn't get reflected in Test2,now when i deleted the Test1 i can able to run Test2 class and i got the out put,


Thanks once again.

[Alex Belisle Turcot]

Test1.java !!!

Your file should be "Test2.java", the same as your public class.

Regards,
Alex

[Narayana.Vaddi]

Before creating the Test2.java class i ran another piece of code which is no where related to our conversation. These two are different, but as a regular mistake i used the same name in both of the examples...and i faced that problem.Now it got resolved.

Thanks.

[Ben Souther]

"Narayana",
Please check your private messages.