Re: Dynamic method calls
Denis Palas wrote:
Dear All
I am trying to use dynamic method calls, and have written the below code,
but not getting any results. Could you please help to point out my mistakes?
Thank you in advance
Denis
// ------------------------------------- My code -------------------------
First, fix any compilation errors.
import java.lang.reflect.*;
Assiduously avoid use of reflection.
import java.text.*;
import java.util.*;
public class TestClass {
public static void main(String[] args) throws Exception {
You should indent code (using spaces, not TABs) that you post, to enhance
readability.
....
Object myres=0 ;
This only works in Java 5 +. You might have made the intent clearer by
declaring the variable as Integer.
Why the throwaway initialization anyway?
String Functionstest[][]= {
Java programming convention is that variable and method names begin with a
lower-case letter, and that each subsequent "word" component begin with an
upper-case letter: "functionsTest'.
{"Mult1","1","2","3"},
....
for (int j = 0; j < Functionstest[0].length - 1; j++) {
parameterTypes[j] = Integer.TYPE;
So "Mult1" is a parameter of Integer.TYPE.
parameters[j] = new Integer(Functionstest[0][j+1]);
}
Method m = c.getMethod(Functionstest[0][0], parameterTypes);
You've already declared "Functionstest[0][0]" to be an Integer.TYPE parameter,
despite that its value does not parse to an integer. It should not also be a
method name.
myres = m.invoke(this, parameters);
Kaboom!
} // End Try
catch (IllegalAccessException e) { }
catch (InvocationTargetException e) { }
catch (NoSuchMethodException e) { }
You should not ignore Exceptions. The error messages probably would have led
you to a solution by now.
System.out.println("The result is = " + myres);
"myRes".
If this is an exercise to learn reflection, it's useful. Otherwise there are
better ways to accomplish the task.
- Lew