Invoke method with wrong parameters : Method « Reflection « Java Tutorial

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import java.lang.reflect.Method;

public class MethodTroubleToo {
  public void ping() {
    System.out.format("PONG!%n");
  }

  public static void main(String... args) {
    try {
      MethodTroubleToo mtt = new MethodTroubleToo();
      Method m = MethodTroubleToo.class.getMethod("ping");

      switch (Integer.parseInt(args[0])) {
      case 0:
        m.invoke(mtt); // works
        break;
      case 1:
        m.invoke(mtt, null); // works (expect compiler warning)
        break;
      case 2:
        Object arg2 = null;
        m.invoke(mtt, arg2); // IllegalArgumentException
        break;
      case 3:
        m.invoke(mtt, new Object[0]); // works
        break;
      case 4:
        Object arg4 = new Object[0];
        m.invoke(mtt, arg4); // IllegalArgumentException
        break;
      default:
        System.out.format("Test not found%n");
      }

      // production code should handle these exceptions more gracefully
    } catch (Exception x) {
      x.printStackTrace();
    }
  }
}