Constant specific class body

[Marco Antonio]

Hallo!

I have a doubt about the "constant specific class body".

The compiler doesn't complaint with this code:

class Other{
  enum Colours{
    RED(10),
    WHITE(){
      int getBrilliance(){
        return 500;
      }
            
      void setBrilliance(int _brilliance){
        this.brilliance = _brilliance;
      }
    },
    BLUE(100);
    
    int brilliance;
    
    Colours(){
      this.brilliance = 200;
    }
    
    Colours(int _brilliance){
      this.brilliance = _brilliance;
    }
    
    int getBrilliance(){
      return this.brilliance;
    }
  }
}
 
class TestEnum{
  public static void main(String[] args){
    System.out.println(Other.Colours.RED + " ---> " + Other.Colours.RED.getBrilliance());
    System.out.println(Other.Colours.WHITE + " ---> " + Other.Colours.WHITE.getBrilliance());
    System.out.println(Other.Colours.BLUE + " ---> " + Other.Colours.BLUE.getBrilliance());
  }
}

If I add the following new sentence in the main method, the compiler complaints:

 
    [B]System.out.println(Other.Colours.WHITE + " ---> " + Other.Colours.WHITE.setBrilliance(0));[/B]

If the constant specific class body only allows override methods, why the compiler doesn't complaint before with the setBrilliance method? Is there any way to use the setBrilliance method?

Thank you for your answer.
[ April 23, 2008: Message edited by: Marco Antonio ]

[Dinesh Tahiliani]

Did you try to complied the code.
I am getting errors when i tried to complied..

Exception in thread "main" java.lang.Error: Unresolved compilation problems:
Other.Colours cannot be resolved
Other.Colours cannot be resolved
Other.Colours cannot be resolved
Other.Colours cannot be resolved
Other.Colours cannot be resolved
Other.Colours cannot be resolved

at TestEnums.main(TestEnums.java:36)

[Marco Antonio]

I don't know what is your problem , but I obtain:

javac TestEnum.java
No compiler errors
java TestEnum
RED ---> 10
WHITE ---> 500
BLUE ---> 100

But, if I add the above sentence, I obtain:

javac TestEnum.java
TestEnum.java:37: cannot find symbol
symbol : method setBrilliance(int)
location: class Other.Colours
System.out.println(Other.Colours.WHITE + " ---> " + Other.Colours.WHITE.setBrilliance(0));
^
1 error


I haven't been able to invoke correctly the setBrilliance method. How can do it?

Thank you again.

[sakthi karthik]

hi Marco Antonio

i think we can not use void methods in System.out.println().
and in Colours enum there is no setBrilliance() so the compiler take that as just a method. so there is no compiler error.
if you try to invoke setBrilliance() in main() the compiler will say "cannot find symbol". since there is no setBrilliance() in Colours.
if you override that method that will work.

i think so. if its wrong, please tell me.

regards
sakthi

[Marco Antonio]

Hallo again and thanks for your answer.

It is true that a void method cannot be used in the System.out.println one. It has been a mistake, sorry! But if you use a method which returns a type in the provided scenario in a previous post, if this method is defined only in a constant specific class body and isn't defined in the enum, as long as you don't try to invoke this method, the compiler doen't complaint. And this is my doubt.

Why the compiler doesn't display an error?

I think that is possible to define methods in a concrete enum through the constant specific class body, that is why the compiler doesn't complaint, but I don't know how to do use of them.

Any idea?

Thanks for all.

[Jose Francisco Ruiz Massieu]

i dont know if you need this still, but anyway, what happen is that the constant-specific class body is regarded as an anonymous (cannot be referred to by a name) class, so we can write whatever valid code inside the c-scb but the only exposed methods are wich are overriding an instance method, and the compiler doesnt complaint because the code is visible inside de c-scb even if you put it as public but not outside but only instace methods, ok???

[geeta vemula]

I think here it is using overridding rules like as below

  class sup {

 method1() {}
  
}

class sub extends sup {

 method1() {} //overiding method1 of sup

 method2() {} // some new method

public static void main(String args[])

   {
      Sup test=new Sub();
      
       test.method1();//ok
        test.method2();//compiler error
          //you cannot call which is not there in super class
    }
}  

So here setBrilliance() is not defined in the enum class. this is what i think.
So correct me if i am wrong..

[Ankit Garg]

ELI Welcome to javaranch!

We have a rule here that you must not Wake The Zombies. And geeta you are right about the reason. Moreover the return type of setBrilliance is void, so I think it cannot be included in println statement even if it is declared in the enum ...

[Taran Singh]

I Dont Know If THis Is D Solution ...

Still ..

package defaultPackage;

import java.io.*;

class Other {
enum Colours {
RED(10), WHITE() {
// Was Used To Get Default Vale For White
/*
int getBrilliance(){
return 500;
}*/

// Can Be Used To Set User Specific Value Here ...
/*int getBrilliance() {
int i = 0;
BufferedReader br = new BufferedReader(new InputStreamReader(
System.in));
try {
i = Integer.parseInt(br.readLine());
} catch (Exception E) {
System.out.println(E);
}
return i;
}
*/},
BLUE(100);

int brilliance;

Colours() {
this.brilliance = 200;
}

Colours(int _brilliance) {
this.brilliance = _brilliance;
}

int getBrilliance() {
return this.brilliance;
}

void setBrilliance(int BB) {
this.brilliance = BB;
}
}
}

class TestEnum {
public static void main(String[] args) {
System.out.println(Other.Colours.RED + " ---> "
+ Other.Colours.RED.getBrilliance());
System.out.println(Other.Colours.WHITE + " ---> "
+ Other.Colours.WHITE.getBrilliance());
System.out.println(Other.Colours.BLUE + " ---> "
+ Other.Colours.BLUE.getBrilliance());

// Simply Call set Brilliance To Set White Specific Value ..
Other.Colours.WHITE.setBrilliance(25);

System.out.println(Other.Colours.WHITE + " ---> "
+ Other.Colours.WHITE.getBrilliance());
}
}