java反射的基本使用

package cn.itcast;public class Person {public String name="aaa";private String password="hhh";public static String repassword="dadwad";public Person(){System.out.println("person");}public Person(String name){this.name=name;System.out.println(this.name);}public Person(String name,int[] score){this.name=name;System.out.println(this.name);for(Object obj:score){System.out.println(obj);}}private Person(String password,int id){this.password=password;System.out.println(this.password+" "+id);}public void add(){System.out.println("person.add()");}public void add(String name){this.name=name;System.out.println(name);}private int add(int a,int b){return a+b;}public static void mian(String[] arg0) {// TODO Auto-generated method stubSystem.out.print("main()");}}

package cn.itcast;import java.lang.reflect.Constructor;import java.lang.reflect.Field;import java.lang.reflect.InvocationTargetException;import java.lang.reflect.Method;public class Test {/** * @param args * @throws Exception  */public static void main(String[] args) throws Exception {// TODO Auto-generated method stub//test1();//test2();//text3();//text4();//text5();//text6();//text7();//text8();//text9();text10();}//反射私有字段private static void text10() throws ClassNotFoundException,NoSuchFieldException, IllegalAccessException {Person p=new Person();Class clazz=Class.forName("cn.itcast.Person");Field name = clazz.getField("name");name.setAccessible(true);System.out.println(name.get(p));name.set(p,"hhah");System.out.println(name.get(p));}//反射公有字段private static void text9() throws ClassNotFoundException,NoSuchFieldException, IllegalAccessException {Person p=new Person();Class clazz=Class.forName("cn.itcast.Person");Field name = clazz.getField("name");System.out.print(name.get(p));}//反射主函数private static void text8() throws ClassNotFoundException,NoSuchMethodException, IllegalAccessException,InvocationTargetException {Person p=new Person();Class clazz=Class.forName("cn.itcast.Person");Method men = clazz.getDeclaredMethod("mian",String[].class);men.setAccessible(true);System.out.print(men.invoke(p,(Object)(new String[]{"123","awdw"})));}//反射私有有参函数private static void text7() throws ClassNotFoundException,NoSuchMethodException, IllegalAccessException,InvocationTargetException {Person p=new Person();Class clazz=Class.forName("cn.itcast.Person");Method men = clazz.getDeclaredMethod("add",int.class,int.class);men.setAccessible(true);System.out.print(men.invoke(p, 1,2));}//反射有参函数private static void text6() throws ClassNotFoundException,NoSuchMethodException, IllegalAccessException,InvocationTargetException {Person p=new Person();Class clazz=Class.forName("cn.itcast.Person");Method men = clazz.getMethod("add",String.class);men.invoke(p,"zhangsan");}//反射无参函数private static void text5() throws ClassNotFoundException,NoSuchMethodException, IllegalAccessException,InvocationTargetException {Person p=new Person();Class clazz=Class.forName("cn.itcast.Person");Method men = clazz.getMethod("add", null);men.invoke(p, null);}//反射私有多参构造函数private static void text4() throws ClassNotFoundException,NoSuchMethodException, InstantiationException,IllegalAccessException, InvocationTargetException {Class clazz=Class.forName("cn.itcast.Person");Constructor con = clazz.getDeclaredConstructor(String.class,int.class);con.setAccessible(true);//强暴私有成员Person p=(Person) con.newInstance("enen",12);}//反射多参构造方法private static void text3() throws ClassNotFoundException,NoSuchMethodException, InstantiationException,IllegalAccessException, InvocationTargetException {Class clazz=Class.forName("cn.itcast.Person");Constructor con = clazz.getConstructor(String.class,int[].class);Person p=(Person) con.newInstance("dawdwad",new int[]{1,2,3,5});}//反射有参构造方法private static void test2() throws ClassNotFoundException,NoSuchMethodException, InstantiationException,IllegalAccessException, InvocationTargetException {Class clazz=Class.forName("cn.itcast.Person");Constructor con = clazz.getConstructor(String.class);Person p=(Person) con.newInstance("zhangsan");}//反射无参构造方法private static void test1() throws ClassNotFoundException,NoSuchMethodException, InstantiationException,IllegalAccessException, InvocationTargetException {Class clazz=Class.forName("cn.itcast.Person");Constructor can = clazz.getConstructor(null);Person p=(Person) can.newInstance(null);}}