package gtPlusPlus.core.util;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

public class ClassUtils {


	/*@ if (isPresent("com.optionaldependency.DependencyClass")) {
    //  This block will never execute when the dependency is not present
    //  There is therefore no more risk of code throwing NoClassDefFoundException.
    executeCodeLinkingToDependency();
	}*/
	public static boolean isPresent(String className) {
		try {
			Class.forName(className);
			return true;
		} catch (Throwable ex) {
			// Class or one of its dependencies is not present...
			return false;
		}
	}

	public static Method getMethodViaReflection(Class<?> lookupClass, String methodName, boolean invoke) throws Exception{
		Class<? extends Class> lookup = lookupClass.getClass();
		Method m = lookup.getDeclaredMethod(methodName);
		m.setAccessible(true);// Abracadabra 
		if (invoke){
			m.invoke(lookup);// now its OK
		}
		return m;
	}

	public static Class getNonPublicClass(String className){
		Class<?> c = null;
		try {
			c = Class.forName(className);
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		//full package name --------^^^^^^^^^^
		//or simpler without Class.forName:
		//Class<package1.A> c = package1.A.class;

		if (null != c){
			//In our case we need to use
			Constructor<?> constructor = null;
			try {
				constructor = c.getDeclaredConstructor();
			} catch (NoSuchMethodException | SecurityException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			//note: getConstructor() can return only public constructors
			//so we needed to search for any Declared constructor

			//now we need to make this constructor accessible
			if (null != constructor){
				constructor.setAccessible(true);//ABRACADABRA!

				try {
					Object o = constructor.newInstance();
					return (Class) o;
				} catch (InstantiationException | IllegalAccessException
						| IllegalArgumentException | InvocationTargetException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		}
		return null;
	}



}