java_jdbc_反射

package cn.itcast.Reflect;

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

public class ReflectDemo {

	public static void main(String[] args) throws Exception {
		// TODO Auto-generated method stub
		Class clazz = User.class;

		Object obj=create(clazz);

		System.out.println(obj);

		invoke1(obj,"showMessage");
		System.out.println("-------------------------");
		field(clazz);
	}
	//创建对象
	static Object create(Class clazz) throws Exception{
		Constructor con = clazz.getConstructor(String.class);
		Object obj  = con.newInstance("test name");
		return obj;

	}

	//调用方法
	static void invoke1(Object obj,String methodName) throws Exception{

		Method[] ms = obj.getClass().getMethods();
		for(Method m:ms){
			System.out.println(m.getName());
			if(methodName.equals(m.getName())){
				m.invoke(obj, null);
			}
		}

		Method m = obj.getClass().getMethod(methodName, null);
		m.invoke(obj, null);
	}

	static void field(Class clazz) throws Exception{

		Field[] fs = clazz.getDeclaredFields();
		//不会便利出私有变量
//		fs = clazz.getFields();
		for(Field f : fs){

			System.out.println(f.getName());
		}

	}
}