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Java error: class, interface or enum expected

I need to know the result of this code. But that does not work. The code may be incorrect. I am still involved in using Java, and I tried to fix this for several hours, but still no luck.

Here is the code:

public class A 
{ 
    public A() 
    {
        System.out.println ("A");
    }
}
public class B extends A 
{
    public B() 
    {
        System.out.println ("B");
    }
}
public class C extends B 
{ 
    public C() 
    {
        System.out.println ("C");
    }
}

public static void main(String args[]) {

    A a = new A();  
    B b = new B();  
    C c = new C();  
}

Can someone tell me what is wrong or not in the code?

+3
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4 answers

For instance:

public class Example {

    public static void main(String...args) {
        new C();
    }

    public static class A {
        public A() {
            System.out.println("A");
        }
    }
    public static class B extends A {
        public B() {
            System.out.println("B");
        }
    }
    public static class C extends B {
        public C() {
            System.out.println("C");
        }
    }
}

Also note that this may not print what you expect. This will actually print:

A
B
C

Why? Constructors are always bound to a superclass.

+2
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Put your main method in a class.

Filename : DemoClass.java

class A 
{ 
    public A() 
    {
        System.out.println ("A");
    }
}
class B extends A 
{
    public B() 
    {
        System.out.println ("B");
    }
}
class C extends B 
{ 
    public C() 
    {
        System.out.println ("C");
    }
}

public class DemoClass {

   public static void main(String args[]) {

       A a = new A();  
       B b = new B();  
       C c = new C();  
   }
}

: , A B C public java .

java . .. DemoClass , DemoClass.java

Java- : java

+5

, , . .

, (super()).

: A.java, B.java, C.java InheritenceTest.java.

public class InheritenceTest {
    public class A {
        public A() {
            System.out.println("A");
        }
    }

    public class B extends A {
        public B() {
            System.out.println("B");
        }
    }

    public class C extends B {
        public C() {
            System.out.println("C");
        }
    }

    public static void main(String args[]) {
        InheritenceTest i = new InheritenceTest();
        A a = i.new A();
        B b = i.new B();
        C c = i.new C();
    }
}

:

A
A
B
A
B
C
0

: 1 1 java , . , "" ( ). , .

: . , void .

: , , . ( B A, C B, A).

A
A  
B
A
B
C

*due to A() it prints A, then due to B() it prints A B and finally due to C() it prints A B C.

:

//Filename: A.java
public class A { 
    public A() {
        System.out.println ("A");
    }
}

//Filename: B.java
public class B extends A { 
    public B() {
        System.out.println ("B");
    }
}

//Filename: C.java
public class C extends B { 
    public C() {
        System.out.println ("C");
    }
}

//Filename: Test.java
//use a Test class for testing
public class Test {
   public static void main(String args[]) {
       A a = new A();  
       B b = new B();  
       C c = new C();  
   }
}
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