java中通过放射机制创建对象的两种方式

import java.lang.reflect.Constructor;import java.lang.reflect.Field;import java.lang.reflect.Method;import java.lang.reflect.Constructor;import java.lang.reflect.Field;import java.lang.reflect.Method;/** * @author ErnestFei * 使用Class来创建对象 */public class ClassTest {public static void main(String[] args) {//直接通过clss来获得初始化对象 //方式一Class classPerson = Person.class;//这里并没有被初始化，知识加载try {Object obj = classPerson.newInstance();Person person = (Person)obj;person.setName("张三");person.setAge(11);person.setSex("女");System.out.println(person.getName());} catch (InstantiationException | IllegalAccessException e) {e.printStackTrace();}//方式二：通过构造类来获取Class classPerson = Person.class;try {Constructor con = classPerson.getDeclaredConstructor(String.class,int.class,String.class);// con.setAccessible(true);Object obj = con.newInstance("张三",44,"男");//Person per = (Person) obj;per.setName("李四");System.out.println(per.getName());Method method = classPerson.getDeclaredMethod("fun");method.setAccessible(true);method.invoke(obj);//这个应用调用这个对象的方法//调用属性Field field = classPerson.getDeclaredField("name");field.setAccessible(true);//权限为私有的必须设置获取权限的属性field.set(obj, "张三");field.get(obj);Person per2 = (Person) obj;System.out.println(per2.getName());} catch (Exception e) {e.printStackTrace();} }}