Dynamic [Runtime] type casting in Java

Question

Hello,
This is my requirement.
I have a method that takes class name as a parameter.
Ex:
Object myMethod(String classname){
Object xyz = getObject(); //userdefine method which returns some object
/*<b>I need to typecast above object with the class name passed as the method parameter</b>*/
/*<b>How can i type cast this object</b>*/
Object obj = (classname) xyz;
return obj;
In the above example, how can i dynamically typecast the object with class whose name is passed as the method parameter?

Answer 1

Hello,
This is my requirement.
I have a method that takes class name as a parameter.
Ex:
Object myMethod(String classname){
Object xyz = getObject(); //userdefine method which
returns some object
/*<b>I need to typecast above object with the class
name passed as the method parameter</b>*/
/*<b>How can i type cast this object</b>*/
Object obj = (classname) xyz;
return obj;
In the above example, how can i dynamically typecast
the object with class whose name is passed as the
method parameter?Perhaps a little more background on the project (what you are trying to do) will help the experts here answer?
/*with a class that takes a noarg constructor*/
public Object getObject(String classname) throws Exception
  //might want to get a bit more specific with which exceptions it will throw
  return Class.forName(classname).newInstance();
}Do I think this sometimes is indicative (perhaps even more often than not), of a possible design flaw? Yes..
It gets a little trickier if you have constructors (you have to create a Class object representing the string with the .forName(..) ..and then use some reflection to determine constructors and then a bit of logic to determine which of those to use...)
~Dave