How to check if a java class has a particular method in it?

One method is mentioned by @missingfaktor and another is below (if you know the name and parameters of the api).

Say you have one method which takes no args:

Method methodToFind = null;
try {
  methodToFind = YouClassName.class.getMethod("myMethodToFind", (Class<?>[]) null);
} catch (NoSuchMethodException | SecurityException e) {
  // Your exception handling goes here
}

Invoke it if present:

if(methodToFind == null) {
   // Method not found.
} else {
   // Method found. You can invoke the method like
   methodToFind.invoke(<object_on_which_to_call_the_method>, (Object[]) null);
}

Say you have one method which takes native int args:

Method methodToFind = null;
methodToFind = YouClassName.class.getMethod("myMethodToFind", new Class[] { int.class });

Invoke it if present:

if(methodToFind == null) {
   // Method not found.
} else {
   // Method found. You can invoke the method like
   methodToFind.invoke(<object_on_which_to_call_the_method>, invoke(this,
      Integer.valueOf(10)));
}

Say you have one method which takes boxed Integer args:

Method methodToFind = null;
methodToFind = YouClassName.class.getMethod("myMethodToFind", new Class[] { Integer.class });

Invoke it if present:

if(methodToFind == null) {
   // Method not found.
} else {
   // Method found. You can invoke the method like
   methodToFind.invoke(<object_on_which_to_call_the_method>, invoke(this,
      Integer.valueOf(10)));
}

Using the above soln to invoke method won’t give you compilation errors.
Updated as per @Foumpie