A.java

class A {

  public Object foo;
  public Object bar;
  public Object get(String propertyName) {
    // hashmap lookup for the rest of the properties
  }

}

Test.java

public class Test {
    @Test
    public void testIt(){
        Object target = new A();
        String prop = "foo";
        MethodHandle test = Binder
                .from(boolean.class, target.getClass(), String.class)
                .convert(boolean.class, Object.class, String.class)
                .invokeStatic(lookup(), Test.class, "hasNativeProp");

        // blows if field doesn't exist
        MethodHandle fieldHandle = Binder.from(Object.class, target.getClass(), String.class)
                .drop(1)
                .getField(lookup(), prop);

        // blows if method doesn't exist
        MethodHandle getterHandle = Binder.from(Object.class, target.getClass(), String.class)
                .invokeVirtual(lookup(), "get");
        MethodHandle handle = Binder.from(Object.class, Object.class, String.class)
                .branch(test, fieldHandle, getterHandle);

        System.out.println(handle.invoke(target, prop));

    }

    public static boolean hasNativeProp(Object obj, String name) {
        try {
          obj.getClass().getDeclaredField(name);
          return true;
        } catch (NoSuchFieldBlah e) {
          return false;
        }
    }

direct field access for fields, method access for the rest