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need help with question

 
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public class ObjectTest2 {
String s;

public void ObjectTest2(){
s = "Constructor";
}

public void printString() {
System.out.println(s);
}

public static void main(String args[]) {
ObjectTest2 o = new ObjectTest2();
o.printString();
}
}



could someone please tell me why it is printing null in the question above ???
 
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Its not a constructor rather its a method. Your s instance variable is assigned to null. There is nowhere explicit assignment of s. So SOP(s) prints null.

Its better not to use class name as a method. This will just create confusion.


Naseem
 
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it is because u have declared a method and not a constructor as ObjectTest2().so as of now the string reference has a value null.since there is no constructor for the class provided..s = "Constructor";won't happen..thus null is the output.

constructors don't have a return type...not even void.
following would work as u want....

public class ObjectTest2 {
String s;

public ObjectTest2(){
s = "Constructor";
}

public void printString() {
System.out.println(s);
}

public static void main(String args[]) {
ObjectTest2 o = new ObjectTest2();
o.printString();
}
}
 
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