Inner classes help
Hello, I was just wondering if someone can help me understand inner classes a little. If I have the following code:
class Parent
private String myString = new String(�I am parent�);
public void writeIt()
System.out.println(myString);
public void displayIt()
System.out.println((new InnerParent()).readMyString());
class InnerParent
public String readMyString()
return myString;
class Child extends Parent
private String myString = new String(�I am child�);
public void writeIt()
System.out.println(myString);
If we execute the following lines on the code
Child myChild = new Child();
Parent myParent = new Parent();
myChild.writeIt();
myParent.writeIt();
myChild.displayIt();
myParent.displayIt();
Why does the following code display?
I am child
I am child
I am parent
I am parent
==
Thanks!
Child myChild = new Child();
Parent myParent = new myChild();you again made a mistake,
it should be
Child myChild = new Child();
Parent myParent = new Child();
and now the output is
I am child
I am child
I am parent
I am parent
because, myChild.writeIt(); displays the stirng, I am child, straightforward, when it comes to myParent.writeIt(); it displays the string I am child because, myParent is of the type Child() which has been casted back to Parent, since child extends parent this can be done, and so, it just behaves as if it is a child, and so it displays I am child. when it comes to myChild.displayIt(), it uses the string in the Parent class, since it extends Parent and it does not override that method, it has to use that string ,and so it displays I am Parent, and similarly for the myParent.displayIt(), also it displays I am Parent. Hope you Understood now.
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// test1.java
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