Question

I have a problem in copying the data in array from object variable which is also a type String.

Can any one explain this

 String[] childRoot = null;
 int k = 1;
 System.out.println(" Name " + d.getName()); 
 childRoot[k]=d.getName();                         *
 k++;

output

Name try 1
java.lang.NullPointerException
at *  

Detail for :getName

  java.lang.String getName()
  Returns the name of this object 

Answer 1

Yes, you have to initialize an array before you can use it. If you don’t want to initialize, there’s an alternative way you can fill up the array like this:

String[] childRoot = {null, d.getName()};

I put the first element as null, because you wanted the name to be in index 1 which is the 2nd element of the array.